The Patent Trial and Appeal Board 
April 8May 28, 2024 , 2024 
and Inter Partes Review 
Christopher T. Zirpoli 
The 2011 Leahy-Smith America Invents Act (AIA) is widely viewed as the most significant 
The 2011 Leahy-Smith America Invents Act (AIA) is widely viewed as the most significant 
Legislative Attorney 
Legislative Attorney 
patent statute enacted by Congress in over 50 years. Although the AIA made many important 
patent statute enacted by Congress in over 50 years. Although the AIA made many important 
  
  
changes to U.S. patent law, the most practically significant was the creation of the Patent Trial 
changes to U.S. patent law, the most practically significant was the creation of the Patent Trial 
Kevin J. Hickey 
and Appeal Board (PTAB). 
and Appeal Board (PTAB). 
Legislative Attorney 
Legislative Attorney     
PTAB is a tribunal within the U.S. Patent and Trademark Office (USPTO), the federal agency 
PTAB is a tribunal within the U.S. Patent and Trademark Office (USPTO), the federal agency 
responsible for reviewing patent applications and granting patents. The AIA created PTAB and responsible for reviewing patent applications and granting patents. The AIA created PTAB and 
 
 
granted it authority to hear several new types of administrative challenges to the validity of 
granted it authority to hear several new types of administrative challenges to the validity of 
patents previously granted by USPTO. These challenges, which were also created by the AIA, include inter partes review patents previously granted by USPTO. These challenges, which were also created by the AIA, include inter partes review 
(IPR) and post-grant review (PGR). IPRs and PGRs are typically decided by a panel of three administrative patent judges (IPR) and post-grant review (PGR). IPRs and PGRs are typically decided by a panel of three administrative patent judges 
(APJs). (APJs). 
Entities accused of patent infringement have always been able to challenge the validity of patents asserted against them in 
Entities accused of patent infringement have always been able to challenge the validity of patents asserted against them in 
federal court. Because those patents were reviewed and granted by USPTO, patents carry a presumption of validity when federal court. Because those patents were reviewed and granted by USPTO, patents carry a presumption of validity when 
challenged in court. Patent invalidity must be demonstrated by a higher standard of proof (clear and convincing evidence) challenged in court. Patent invalidity must be demonstrated by a higher standard of proof (clear and convincing evidence) 
than the standard used for most issues in civil litigation (preponderance of the evidence). Litigating a patent case to a final than the standard used for most issues in civil litigation (preponderance of the evidence). Litigating a patent case to a final 
judgment in a federal court is time-consuming and expensive: it typically takes several years, with average legal costs judgment in a federal court is time-consuming and expensive: it typically takes several years, with average legal costs 
amounting to over a million dollars. In addition, because of judicial standing requirements, an entity can usually ask a court amounting to over a million dollars. In addition, because of judicial standing requirements, an entity can usually ask a court 
to decide the validity of a patent only if they have been sued or at least threatened with a patent lawsuit. to decide the validity of a patent only if they have been sued or at least threatened with a patent lawsuit. 
Congress’s stated aim when creating IPR and PGR was to improve patent quality by providing a more efficient means to 
Congress’s stated aim when creating IPR and PGR was to improve patent quality by providing a more efficient means to 
adjudicate patent validity issues. Congress was also concerned that poor-quality patents fueled litigation by so-called “patent adjudicate patent validity issues. Congress was also concerned that poor-quality patents fueled litigation by so-called “patent 
trolls,” a pejorative term for patent plaintiffs that do not manufacture or sell the patented products. From the perspective of a trolls,” a pejorative term for patent plaintiffs that do not manufacture or sell the patented products. From the perspective of a 
person accused of patent infringement (or worried about being sued), PTAB procedures are often more advantageous than person accused of patent infringement (or worried about being sued), PTAB procedures are often more advantageous than 
federal court litigation in that they are faster, cheaper, and use a lower standard of proof. By statute, IPRs and PGRs are federal court litigation in that they are faster, cheaper, and use a lower standard of proof. By statute, IPRs and PGRs are 
supposed to reach a final determination no later than one year after PTAB decides to institute the proceeding. The supposed to reach a final determination no later than one year after PTAB decides to institute the proceeding. The 
administrative procedures are more streamlined than civil litigation, with average legal costs typically in the hundreds of administrative procedures are more streamlined than civil litigation, with average legal costs typically in the hundreds of 
thousands of dollars (as opposed to millions). In addition, PTAB does not require standing, so any person other than the thousands of dollars (as opposed to millions). In addition, PTAB does not require standing, so any person other than the 
patent holder can challenge a patent before PTAB. As a result, it has become common for entities sued for patent patent holder can challenge a patent before PTAB. As a result, it has become common for entities sued for patent 
infringement in federal court or before the U.S. International Trade Commission to petition PTAB to institute an IPR and infringement in federal court or before the U.S. International Trade Commission to petition PTAB to institute an IPR and 
seek to challenge the patent in that forum. seek to challenge the patent in that forum. 
PTAB procedures—and IPR in particular—have aroused controversy among patent stakeholders since the enactment of the 
PTAB procedures—and IPR in particular—have aroused controversy among patent stakeholders since the enactment of the 
AIA. Critics of PTAB argue that it is biased against patent holders, creates uncertainty in patent rights, and discourages AIA. Critics of PTAB argue that it is biased against patent holders, creates uncertainty in patent rights, and discourages 
investment in innovation. PTAB critics further maintain that IPR is unfair to patent holders, who have successfully obtained a investment in innovation. PTAB critics further maintain that IPR is unfair to patent holders, who have successfully obtained a 
patent before USPTO but must now again defend their patent’s validity before the same agency. patent before USPTO but must now again defend their patent’s validity before the same agency. 
Since 2011, the Supreme Court has heard a number of cases concerning PTAB. In 
Since 2011, the Supreme Court has heard a number of cases concerning PTAB. In 
Oil States Energy Services v. Greene’s 
Energy Group, the Supreme Court rejected a constitutional challenge to IPR, holding that challenges to already-issued , the Supreme Court rejected a constitutional challenge to IPR, holding that challenges to already-issued 
patents in an administrative forum did not violate the Seventh Amendment or Article III of the U.S. Constitution. In patents in an administrative forum did not violate the Seventh Amendment or Article III of the U.S. Constitution. In 
United 
States v. Arthrex Inc., the Court held that the unreviewable authority exercised by APJs violated the Constitution’s , the Court held that the unreviewable authority exercised by APJs violated the Constitution’s 
Appointments Clause but spared PTAB by granting the Director of USPTO discretionary authority to review PTAB Appointments Clause but spared PTAB by granting the Director of USPTO discretionary authority to review PTAB 
decisions. decisions. 
Members of Congress have examined whether to maintain PTAB as it exists or to modify IPR and PGR procedures, with 
Members of Congress have examined whether to maintain PTAB as it exists or to modify IPR and PGR procedures, with 
both House and Senate committees holding hearings on the issue. Legislative proposals introduced in recent Congresses both House and Senate committees holding hearings on the issue. Legislative proposals introduced in recent Congresses 
include bills that would abolish PTAB entirely or make various procedural and substantive reforms to PTAB. For their part, include bills that would abolish PTAB entirely or make various procedural and substantive reforms to PTAB. For their part, 
USPTO and PTAB have issued regulationsUSPTO and PTAB have issued regulations
 or, precedential decisions precedential decisions
, and other guidance on issues including USPTO Director review, repeat IPR  on issues including USPTO Director review, repeat IPR 
petitions, and when PTAB should exercise its discretion to decline to institute (i.e., hear) an IPR or PGR. petitions, and when PTAB should exercise its discretion to decline to institute (i.e., hear) an IPR or PGR. 
In 2024In 2023, USPTO , USPTO 
issued an advanced noticeissued notices of proposed rulemaking ( of proposed rulemaking (
ANPRM) on manyNPRMs) on some of these issues.  of these issues. 
 
 
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4445  The Patent Trial and Appeal Board and Inter Partes Review 
 
Contents 
Introduction ..................................................................................................................................... 1 
Overview of U.S. Patent Law .......................................................................................................... 2 
What Are Patents? ..................................................................................................................... 2 
What Inventions Can Be Patented? ........................................................................................... 3 
Eligible Subject Matter Requirement .................................................................................. 3 
Novelty Requirement .......................................................................................................... 4 
Nonobviousness Requirement ............................................................................................ 4 
Utility Requirement ............................................................................................................ 5 
Requirements for Specification and Claims ........................................................................ 5 
How Do Inventors Obtain a Patent? .......................................................................................... 6 
How Do Courts Adjudicate Patent Rights? ............................................................................... 6 
What Was USPTO’s Role in Patent Adjudication Prior to the AIA? ........................................ 8 
Overview of the America Invents Act and PTAB ............................................................................ 9 
The AIA’s Key Changes to Patent Law ..................................................................................... 9 
PTAB’s Structure..................................................................................................................... 10 
PTAB Post-Grant Proceedings ....................................................................................................... 11 
Inter Partes Review .................................................................................................................. 11 
Standing, Timing, and Grounds to Petition for IPR .......................................................... 12 
Discretionary Institution of IPR ........................................................................................ 12 
IPR Process Following Institution .................................................................................... 13 
Discovery in IPR ............................................................................................................... 15 
IPR Final Decisions, Director Review, and Appeals. ........................................................ 16 
IPR Statistics ..................................................................................................................... 17 
Post-Grant Review .................................................................................................................. 21 
Covered Business Method Review ......................................................................................... 22 
Comparison of PTAB and Other Post-Grant Proceedings ...................................................... 22 
PTAB at the Supreme Court .......................................................................................................... 23 
Statutory Interpretation Cases ................................................................................................. 24 
Cuozzo Speed Technologies, LLC v. Lee ........................................................................... 24 
SAS Institute, Inc. v. Iancu ................................................................................................ 26 
Return Mail, Inc. v. U.S. Postal Service ............................................................................ 27 
Thryv, Inc. v. Click-to-Call Technologies, LP ................................................................... 29 
Constitutional Challenges to IPR ............................................................................................ 30 
Oil States Energy Services, LLC v. Greene’s Energy Group, LLC .................................... 30 
United States v. Arthrex ..................................................................................................... 31 
Current Debates and Proposed Reforms ........................................................................................ 33 
What Roles Do the USPTO Director and PTAB Management Play in PTAB 
Decisions? ............................................................................................................................ 33 
Interim Director Review Process ...................................................................................... 33 
Concerns Regarding Transparency and APJ Independence .............................................. 35 
Who Has Standing to Petition PTAB and Appeal Its Decisions? ............................................ 37 
What Should Be PTAB’s Standards for Invalidation and Claim Construction? ..................... 38 
Invalidity: Preponderance of Evidence or Clear and Convincing Evidence? ................... 38 
Claim Construction: Should USPTO or Congress Decide the Right Standard? ............... 39 
When Should PTAB Deny Institution of an IPR? ................................................................... 40 
Petitions Raising Previously Presented Prior Art and Arguments .................................... 40. 41 
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Serial Petitions .................................................................................................................. 42 
Parallel Petitions ............................................................................................................... 4344 
Parallel District Court Litigation ...................................................................................... 4445 
Patent Claims Already Upheld by a District Court ........................................................... 47 
Conclusion ..................................................................................................................................... 48 
 
 
Figures 
Figure 1. IPR and PGR Outcomes by Petition in FY2023 ............................................................ 18 
    
Tables 
Table 1. USPTO Post-Grant Proceedings ...................................................................................... 23 
    
Contacts 
Author Information ........................................................................................................................ 48 
  
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The Patent Trial and Appeal Board and Inter Partes Review 
 
Introduction 
The Patent Trial and Appeal Board (PTAB), which is part of the U.S. Patent and Trademark The Patent Trial and Appeal Board (PTAB), which is part of the U.S. Patent and Trademark 
Office (USPTO), was created by Congress in 2011 through the Leahy-Smith America Invents Act Office (USPTO), was created by Congress in 2011 through the Leahy-Smith America Invents Act 
(AIA).1 The AIA established new administrative procedures to challenge patent validity called (AIA).1 The AIA established new administrative procedures to challenge patent validity called 
inter partes review (IPR) and  (IPR) and 
post-grant review (PGR).2 While entities accused of patent  (PGR).2 While entities accused of patent 
infringement have long been able to challenge the validity of the patents asserted against them in infringement have long been able to challenge the validity of the patents asserted against them in 
court, IPR and PGR allow a party to petition PTAB to hear a challenge to the validity of an court, IPR and PGR allow a party to petition PTAB to hear a challenge to the validity of an 
already-issued patent in an administrative forum, regardless of whether the petitioner has been already-issued patent in an administrative forum, regardless of whether the petitioner has been 
sued or threatened with suit for patent infringement.3  sued or threatened with suit for patent infringement.3  
IPR and PGR thus provide a way for anyone to challenge patents before USPTO and, if 
IPR and PGR thus provide a way for anyone to challenge patents before USPTO and, if 
successful, cancel patent claims that PTAB concludes should have never issued.4 From an successful, cancel patent claims that PTAB concludes should have never issued.4 From an 
accused patent infringer’s perspective, using IPR or PGR to challenge patent validity is often accused patent infringer’s perspective, using IPR or PGR to challenge patent validity is often 
more advantageous than judicial proceedings because PTAB processes are typically faster and more advantageous than judicial proceedings because PTAB processes are typically faster and 
less expensive, and require a lower burden of proof to invalidate patents.5 It is thus common for less expensive, and require a lower burden of proof to invalidate patents.5 It is thus common for 
entities threatened with or sued for patent infringement in court or in the U.S. International Trade entities threatened with or sued for patent infringement in court or in the U.S. International Trade 
Commission (ITC) to petition PTAB to attempt to invalidate the patents asserted against them in Commission (ITC) to petition PTAB to attempt to invalidate the patents asserted against them in 
those other forums.6 those other forums.6 
Congress’s stated purpose in creating PTAB was to “improv[e] patent quality and provid[e] a 
Congress’s stated purpose in creating PTAB was to “improv[e] patent quality and provid[e] a 
more efficient system for challenging patents that should not have issued; and reduc[e] more efficient system for challenging patents that should not have issued; and reduc[e] 
unwarranted litigation costs.”7 Congress also observed that poor-quality patents may fuel unwarranted litigation costs.”7 Congress also observed that poor-quality patents may fuel 
litigation by so-called patent “trolls,”8 a pejorative term for patent plaintiffs that do not litigation by so-called patent “trolls,”8 a pejorative term for patent plaintiffs that do not 
manufacture or sell the patented products.9 On this view, PTAB may be seen as an attempt to manufacture or sell the patented products.9 On this view, PTAB may be seen as an attempt to 
reduce patent-troll litigation by weeding out poor-quality patents.  reduce patent-troll litigation by weeding out poor-quality patents.  
Some stakeholders have criticized PTAB, labeling it a “patent death squad.”10 Critics of PTAB 
Some stakeholders have criticized PTAB, labeling it a “patent death squad.”10 Critics of PTAB 
argue that PTAB has made it too easy to challenge patents, creating uncertainty in patent rights, argue that PTAB has made it too easy to challenge patents, creating uncertainty in patent rights, 
stifling innovation, and discouraging investments in patent-intensive industries and early-stage stifling innovation, and discouraging investments in patent-intensive industries and early-stage 
 
 
1 Pub. L. No. 112-29 (2011). 
1 Pub. L. No. 112-29 (2011). 
2 A third procedure created by the AIA was transitional and sunsetted in 2020. 2 A third procedure created by the AIA was transitional and sunsetted in 2020. 
See infra  “Covered Business Method 
Review.”  
3 
3 
See 35 U.S.C. §§ 31–32. 35 U.S.C. §§ 31–32. 
4 4 
See generally CRS Report R46525,  CRS Report R46525, 
Patent Law: A Handbook for Congress, coordinated by Kevin J. Hickey, at 24–25 , coordinated by Kevin J. Hickey, at 24–25 
(2020). (2020). 
5 
5 
See CRS Report R47267,  CRS Report R47267, 
Patents and Innovation Policy, by Emily G. Blevins, at 10 (2020). , by Emily G. Blevins, at 10 (2020). 
6 6 
See Jeffrey C. Totten,  Jeffrey C. Totten, 
Four Strategies to Stay Litigation in Favor of IPR, FINNEGAN (May 2014), , FINNEGAN (May 2014), 
https://www.finnegan.com/en/insights/articles/four-strategies-to-stay-litigation-in-favor-of-ipr.html. https://www.finnegan.com/en/insights/articles/four-strategies-to-stay-litigation-in-favor-of-ipr.html. 
7 H.R. REP. NO. 112-98, at 39–40 (2011), 
7 H.R. REP. NO. 112-98, at 39–40 (2011), 
as reprinted in 2011 U.S.C.C.A.N. 67, 69.  2011 U.S.C.C.A.N. 67, 69. 
8 H.R. REP. NO. 112-98, at 54 (“A number of patent observers believe the issuance of poor business-method patents 8 H.R. REP. NO. 112-98, at 54 (“A number of patent observers believe the issuance of poor business-method patents 
during the late 1990’s through the early 2000’s led to the patent ‘troll’ lawsuits that compelled the Committee to launch during the late 1990’s through the early 2000’s led to the patent ‘troll’ lawsuits that compelled the Committee to launch 
the patent reform project 6 years ago.”). the patent reform project 6 years ago.”). 
9 9 
See FTC, PATENT ASSERTION ENTITY ACTIVITY: AN FTC STUDY 15–17 (2016) (defining “patent assertion entity”); FTC, PATENT ASSERTION ENTITY ACTIVITY: AN FTC STUDY 15–17 (2016) (defining “patent assertion entity”); 
Halo Elecs., Inc. v. Pulse Elecs., Inc., 579 U.S. 93, 109 (2016) (“Trolls, in the patois of the patent community, are Halo Elecs., Inc. v. Pulse Elecs., Inc., 579 U.S. 93, 109 (2016) (“Trolls, in the patois of the patent community, are 
entities that hold patents for the primary purpose of enforcing them against alleged infringers, often exacting outsized entities that hold patents for the primary purpose of enforcing them against alleged infringers, often exacting outsized 
licensing fees on threat of litigation.”). licensing fees on threat of litigation.”). 
10 10 
See Peter J. Pitts, Peter J. Pitts, 
“Patent Death Squads” vs. Innovation,,
 WALL ST. J. (June 10, 2015, 7:23 PM), WALL ST. J. (June 10, 2015, 7:23 PM), 
https://www.wsj.com/articles/patent-death-squads-vs-innovation-1433978591. https://www.wsj.com/articles/patent-death-squads-vs-innovation-1433978591. 
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startups.11 PTAB critics also argue that administrative challenges to patents are unfair to patent 
startups.11 PTAB critics also argue that administrative challenges to patents are unfair to patent 
holders who have successfully obtained a patent through the USPTO patent prosecution process holders who have successfully obtained a patent through the USPTO patent prosecution process 
but must now again defend their patent’s validity before USPTO.12 but must now again defend their patent’s validity before USPTO.12 
These stakeholder debates have led to proposed reforms to PTAB, both from USPTO itself and 
These stakeholder debates have led to proposed reforms to PTAB, both from USPTO itself and 
from Members of Congress, including multiple bills introduced in the last several Congresses. from Members of Congress, including multiple bills introduced in the last several Congresses. 
This report provides the legal background necessary to understand these debates and the practical This report provides the legal background necessary to understand these debates and the practical 
effects that changes to PTAB may have on technology and innovation. effects that changes to PTAB may have on technology and innovation. 
This report begins with an overview of U.S. patent law, including what patents are, what kinds of 
This report begins with an overview of U.S. patent law, including what patents are, what kinds of 
inventions may be patented, the process of obtaining a patent with USPTO, and how patent inventions may be patented, the process of obtaining a patent with USPTO, and how patent 
owners may enforce their patent rights. It then discusses the AIA and its creation of PTAB, owners may enforce their patent rights. It then discusses the AIA and its creation of PTAB, 
including PTAB’s administrative structure. The report then explains and compares the three types including PTAB’s administrative structure. The report then explains and compares the three types 
of post-grant proceedings established by the AIA, focusing on IPR, the most used of these of post-grant proceedings established by the AIA, focusing on IPR, the most used of these 
proceedings. The report follows with a discussion of several cases involving PTAB decided by proceedings. The report follows with a discussion of several cases involving PTAB decided by 
the Supreme Court. Finally, the report discusses current debates and proposed reforms of PTAB, the Supreme Court. Finally, the report discusses current debates and proposed reforms of PTAB, 
including standing, burdens of proof, discretionary institution of IPRs, claim construction, and the including standing, burdens of proof, discretionary institution of IPRs, claim construction, and the 
role of the USPTO Director in reviewing PTAB decisions. role of the USPTO Director in reviewing PTAB decisions. 
Overview of U.S. Patent Law 
What Are Patents? 
Patents are a form of intellectual property that give their holders the exclusive right to Patents are a form of intellectual property that give their holders the exclusive right to 
practice  their inventions (i.e., make, use, sell, offer to sell, or import them) for a limited period of time. their inventions (i.e., make, use, sell, offer to sell, or import them) for a limited period of time. 
The Constitution gives Congress the power to grant patent rights to inventors by authorizing The Constitution gives Congress the power to grant patent rights to inventors by authorizing 
Congress to “promote the Progress of Science and useful Arts, by securing for limited Times to . . Congress to “promote the Progress of Science and useful Arts, by securing for limited Times to . . 
. Inventors the exclusive Right to their respective . . . Discoveries.”13 Since 1790, Congress has . Inventors the exclusive Right to their respective . . . Discoveries.”13 Since 1790, Congress has 
enacted patent laws granting inventors certain exclusive rights in their inventions for a period of enacted patent laws granting inventors certain exclusive rights in their inventions for a period of 
time.14 (Currently, patents expire 20 years after the date that the patent application that gave rise time.14 (Currently, patents expire 20 years after the date that the patent application that gave rise 
to the patent was filed.15) Patents represent a “quid pro quo” by which the inventor publicly to the patent was filed.15) Patents represent a “quid pro quo” by which the inventor publicly 
discloses an invention in exchange for time-limited, exclusive rights to practice it.16 In the United discloses an invention in exchange for time-limited, exclusive rights to practice it.16 In the United 
States, USPTO is responsible for evaluating patent applications and granting patents on States, USPTO is responsible for evaluating patent applications and granting patents on 
qualifying inventions, as explained below.17  qualifying inventions, as explained below.17  
 
 
11 
11 
See, e.g., id.; ALLIANCE OF U.S. STARTUPS AND INVENTORS FOR JOBS, ; ALLIANCE OF U.S. STARTUPS AND INVENTORS FOR JOBS, 
Why Patents Matter, https://www.usij.org/why-, https://www.usij.org/why-
patents-matter/ (last visited Mar. 28, 2024). patents-matter/ (last visited Mar. 28, 2024). 
12 
12 
See, e.g., Gene Quinn, , Gene Quinn, 
A Kinder, Gentler ‘Death Squad’: Ten Years in, Despite Some Reforms, the USPTO Is Still 
Killing U.S. Patents, IP WATCHDOG (Sept. 19, 2021, 12:15 PM), https://ipwatchdog.com/2021/09/19/kinder-gentler-, IP WATCHDOG (Sept. 19, 2021, 12:15 PM), https://ipwatchdog.com/2021/09/19/kinder-gentler-
death-squad-ten-years-despite-reforms-uspto-still-killing-u-s-patents/id=137765/; Oil States Energy Servs. v. Greene’s death-squad-ten-years-despite-reforms-uspto-still-killing-u-s-patents/id=137765/; Oil States Energy Servs. v. Greene’s 
Energy Grp., 584 U.S. 325, 345–47 (2018) (Gorsuch, J., dissenting). Energy Grp., 584 U.S. 325, 345–47 (2018) (Gorsuch, J., dissenting). 
13 U.S. CONST. art. I, § 8, cl. 8. 
13 U.S. CONST. art. I, § 8, cl. 8. 
14 14 
See, e.g., 35 U.S.C. § 271 (setting forth how patents may be infringed). , 35 U.S.C. § 271 (setting forth how patents may be infringed). 
15 15 
Id. § 154(a)(2). Patent terms can be extended in some circumstances, such as delays by USPTO in reviewing a patent  § 154(a)(2). Patent terms can be extended in some circumstances, such as delays by USPTO in reviewing a patent 
application. application. 
See id. §§ 154(b), 156.  §§ 154(b), 156. 
16 J.E.M. Ag Supply, Inc. v. Pioneer Hi-Bred Int’l, Inc., 534 U.S. 124, 142 (2001) (“The disclosure required by the 
16 J.E.M. Ag Supply, Inc. v. Pioneer Hi-Bred Int’l, Inc., 534 U.S. 124, 142 (2001) (“The disclosure required by the 
Patent Act is ‘the quid pro quo of the right to exclude.’” (quoting Kewanee Oil Co. v. Bicron Corp., 416 U.S. 470, 484 Patent Act is ‘the quid pro quo of the right to exclude.’” (quoting Kewanee Oil Co. v. Bicron Corp., 416 U.S. 470, 484 
(1974))); (1974))); 
see also Universal Oil Prods. Co. v. Globe Oil & Refin. Co., 322 U.S. 471, 484 (1944) (“As a reward for  Universal Oil Prods. Co. v. Globe Oil & Refin. Co., 322 U.S. 471, 484 (1944) (“As a reward for 
inventions and to encourage their disclosure, the United States offers a . . . monopoly to an inventor who refrains from inventions and to encourage their disclosure, the United States offers a . . . monopoly to an inventor who refrains from 
keeping his invention a trade secret. But the quid pro quo is disclosure of a process or device in sufficient detail . . . .”).  keeping his invention a trade secret. But the quid pro quo is disclosure of a process or device in sufficient detail . . . .”).  
17 
17 
See infra “How Do Inventors Obtain a Patent?”. . 
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Once granted, the holder of a valid patent has the exclusive right to make, use, sell, or import the 
Once granted, the holder of a valid patent has the exclusive right to make, use, sell, or import the 
invention in the United States until the patent expires.18 Any other person who practices the invention in the United States until the patent expires.18 Any other person who practices the 
invention without permission from the patent holder infringes the patent and is liable for invention without permission from the patent holder infringes the patent and is liable for 
monetary damages, and possibly subject to injunctive relief, if sued by the patentee.19 Patents monetary damages, and possibly subject to injunctive relief, if sued by the patentee.19 Patents 
have the attributes of personal property, and the patentee may sell or assign the patent to another have the attributes of personal property, and the patentee may sell or assign the patent to another 
person.20 A patentee may also person.20 A patentee may also 
license other persons to practice the invention, granting them  other persons to practice the invention, granting them 
permission to make, use, sell, or import the invention, usually in exchange for consideration (such permission to make, use, sell, or import the invention, usually in exchange for consideration (such 
as monetary royalties).21 as monetary royalties).21 
What Inventions Can Be Patented? 
In order to be patented, an invention must meet four substantive requirements: The invention In order to be patented, an invention must meet four substantive requirements: The invention 
must be (1) directed to patentable (or “eligible”) subject matter, (2) new, (3) nonobvious, and must be (1) directed to patentable (or “eligible”) subject matter, (2) new, (3) nonobvious, and 
(4) useful.22 In addition to these four substantive patentability requirements, the Patent Act (4) useful.22 In addition to these four substantive patentability requirements, the Patent Act 
imposes minimum requirements for the technical disclosure of the invention in the patent imposes minimum requirements for the technical disclosure of the invention in the patent 
application, which must adequately describe and distinctly claim the invention.23 As discussed in application, which must adequately describe and distinctly claim the invention.23 As discussed in 
this report, PTAB administers certain proceedings in which petitioners may seek to invalidate a this report, PTAB administers certain proceedings in which petitioners may seek to invalidate a 
patent previously granted by USPTO on the grounds that the patent fails to satisfy certain of these patent previously granted by USPTO on the grounds that the patent fails to satisfy certain of these 
requirements. This section briefly surveys these patentability requirements. requirements. This section briefly surveys these patentability requirements. 
Eligible Subject Matter Requirement 
The Patent Act allows inventors to obtain patents on any new and useful “process, machine, 
The Patent Act allows inventors to obtain patents on any new and useful “process, machine, 
manufacture, or composition of matter, or . . . improvement thereof.”24 Examples of technological manufacture, or composition of matter, or . . . improvement thereof.”24 Examples of technological 
areas for patentable inventions include pharmaceuticals, biotechnology, chemistry, computer areas for patentable inventions include pharmaceuticals, biotechnology, chemistry, computer 
hardware and software, electrical engineering, mechanical engineering, and manufacturing hardware and software, electrical engineering, mechanical engineering, and manufacturing 
processes.25 By contrast, the Supreme Court has long held that “laws of nature, natural processes.25 By contrast, the Supreme Court has long held that “laws of nature, natural 
phenomena, and abstract ideas” are not patentable.26 The Court has reasoned that to permit a phenomena, and abstract ideas” are not patentable.26 The Court has reasoned that to permit a 
monopoly on the “‘basic tools of scientific and technological work’ . . . might tend to impede monopoly on the “‘basic tools of scientific and technological work’ . . . might tend to impede 
innovation more than it would tend to promote it.”27  innovation more than it would tend to promote it.”27  
In a series of cases in the 2010s, the Supreme Court established a two-step test for patentable 
In a series of cases in the 2010s, the Supreme Court established a two-step test for patentable 
subject matter, sometimes called the subject matter, sometimes called the 
Alice test or the  test or the 
Alice/Mayo framework.28 The first step framework.28 The first step 
 
 
18 35 U.S.C. § 271(a). 
18 35 U.S.C. § 271(a). 
19 19 
Id. §§ 271, 281, 283–285.  §§ 271, 281, 283–285. 
20 20 
Id. § 261.  § 261. 
21 21 
License, BLACK’S LAW DICTIONARY (10th ed. 2014); 35 U.S.C. § 271(a). , BLACK’S LAW DICTIONARY (10th ed. 2014); 35 U.S.C. § 271(a). 
22 22 
See 35 U.S.C. §§ 101–103.  35 U.S.C. §§ 101–103. 
23 23 
Id. § 112;  § 112; 
see generally Hickey,  Hickey, 
supra  notenote 4, at 12–14.  at 12–14. 
24 35 U.S.C. § 101. 24 35 U.S.C. § 101. 
25 25 
See USPTO, PATENT TECHNOLOGY CENTERS MANAGEMENT, https://www.uspto.gov/patent/contact-patents/patent- USPTO, PATENT TECHNOLOGY CENTERS MANAGEMENT, https://www.uspto.gov/patent/contact-patents/patent-
technology-centers-management (last visited Mar. 28, 2024) (listing technological divisions for USPTO examiners).  technology-centers-management (last visited Mar. 28, 2024) (listing technological divisions for USPTO examiners).  
26 Diamond v. Diehr, 450 U.S. 175, 185 (1981); 
26 Diamond v. Diehr, 450 U.S. 175, 185 (1981); 
see generally Hickey,  Hickey, 
supra  notenote 4, at 10–20 (overviewing  at 10–20 (overviewing 
development of the law of patent-eligible subject matter). development of the law of patent-eligible subject matter). 
27 Mayo Collaborative Servs. v. Prometheus Lab’ys, Inc., 566 U.S. 66, 71 (2012) (quoting Gottschalk v. Benson, 409 
27 Mayo Collaborative Servs. v. Prometheus Lab’ys, Inc., 566 U.S. 66, 71 (2012) (quoting Gottschalk v. Benson, 409 
U.S. 63, 67 (1972)). U.S. 63, 67 (1972)). 
28 
28 
See Alice Corp. Pty. Ltd. v. CLS Bank Int’l, 573 U.S. 208 (2014); Ass’n for Molecular Pathology v. Myriad  Alice Corp. Pty. Ltd. v. CLS Bank Int’l, 573 U.S. 208 (2014); Ass’n for Molecular Pathology v. Myriad 
Genetics, Inc., 569 U.S. 576 (2013);Genetics, Inc., 569 U.S. 576 (2013);
 Mayo Collaborative Servs., 566 U.S. at 66. USPTO has issued guidelines for its , 566 U.S. at 66. USPTO has issued guidelines for its 
patent examiners to determine whether a patent application seeks to claim ineligible subject matter. patent examiners to determine whether a patent application seeks to claim ineligible subject matter. 
See 2019 Revised 2019 Revised 
Patent Subject Matter Eligibility Guidance, 84 Fed. Reg. 50 (Jan. 7, 2019). Patent Subject Matter Eligibility Guidance, 84 Fed. Reg. 50 (Jan. 7, 2019). 
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addresses whether the patent claims are “directed to” ineligible subject matter—a law of nature, 
addresses whether the patent claims are “directed to” ineligible subject matter—a law of nature, 
natural phenomenon, or abstract idea.29 If not, the invention is patentable. If directed at ineligible natural phenomenon, or abstract idea.29 If not, the invention is patentable. If directed at ineligible 
subject matter, the invention is not patentable unless the patent claims have an “inventive subject matter, the invention is not patentable unless the patent claims have an “inventive 
concept” under the second step of the concept” under the second step of the 
Alice//
Mayo test. To have an “inventive concept,” the patent test. To have an “inventive concept,” the patent 
claims must contain elements “sufficient to ensure that the patent in practice amounts to claims must contain elements “sufficient to ensure that the patent in practice amounts to 
significantly more than a patent upon the [ineligible concept] itself,” transforming the nature of significantly more than a patent upon the [ineligible concept] itself,” transforming the nature of 
the claim to a patent-eligible the claim to a patent-eligible 
application of ineligible subject matter.30  of ineligible subject matter.30 
Novelty Requirement  
Perhaps the most fundamental requirement for patentability is that the claimed invention must be 
Perhaps the most fundamental requirement for patentability is that the claimed invention must be 
novel (i.e., new). By statute, USPTO cannot issue a patent if “the claimed invention was patented, (i.e., new). By statute, USPTO cannot issue a patent if “the claimed invention was patented, 
described in a printed publication, or in public use, on sale, or otherwise available to the public described in a printed publication, or in public use, on sale, or otherwise available to the public 
before the effective filing date of the claimed invention.”31 In other words, if every element of the before the effective filing date of the claimed invention.”31 In other words, if every element of the 
claimed invention is already disclosed in the claimed invention is already disclosed in the 
prior art—the information available to the public at —the information available to the public at 
the time of the patent application—then the alleged inventor “has added nothing to the total stock the time of the patent application—then the alleged inventor “has added nothing to the total stock 
of knowledge,” and no valid patent may issue to her.32 of knowledge,” and no valid patent may issue to her.32 
Nonobviousness Requirement  
Even if a claimed invention is novel in the narrow sense that it is not “identically disclosed” in a 
Even if a claimed invention is novel in the narrow sense that it is not “identically disclosed” in a 
prior art reference (such as an earlier patent or publication), the invention must further be prior art reference (such as an earlier patent or publication), the invention must further be 
nonobvious to be patentable.33 Specifically, an invention cannot be patented if “the differences  to be patentable.33 Specifically, an invention cannot be patented if “the differences 
between the claimed invention and the prior art are such that the claimed invention as a whole between the claimed invention and the prior art are such that the claimed invention as a whole 
would have been obvious . . . to a person having ordinary skill” in the relevant technology.34 would have been obvious . . . to a person having ordinary skill” in the relevant technology.34 
When determining obviousness, courts may evaluate considerations such as “commercial success, When determining obviousness, courts may evaluate considerations such as “commercial success, 
long felt but unsolved needs, [or] failure of others . . . to give light to the circumstances long felt but unsolved needs, [or] failure of others . . . to give light to the circumstances 
surrounding the origin of the subject matter sought to be patented.”35 By its nature, obviousness is surrounding the origin of the subject matter sought to be patented.”35 By its nature, obviousness is 
an “expansive and flexible” inquiry that cannot be reduced to narrow, rigid tests.36 That said, if an an “expansive and flexible” inquiry that cannot be reduced to narrow, rigid tests.36 That said, if an 
invention merely combines “familiar elements according to known methods,” yielding only invention merely combines “familiar elements according to known methods,” yielding only 
“predictable results,” it is likely to be deemed obvious.37 “predictable results,” it is likely to be deemed obvious.37 
 
 
29 
29 
Alice Corp., 573 U.S. at 217. ., 573 U.S. at 217. 
30 30 
Id. (quoting  (quoting 
Mayo Collaborative Servs., 566 U.S. at 73). , 566 U.S. at 73). 
31 35 U.S.C. § 102(a)(1). There are certain exceptions to this requirement when, for example, the prior art disclosure 31 35 U.S.C. § 102(a)(1). There are certain exceptions to this requirement when, for example, the prior art disclosure 
derives from the inventor and the patent application is made within one year of the disclosure. derives from the inventor and the patent application is made within one year of the disclosure. 
Id. § 102(b)(1).  § 102(b)(1). 
32 Great Atl. & Pac. Tea Co. v. Supermarket Equip. Corp., 340 U.S. 147, 153 (1950); 
32 Great Atl. & Pac. Tea Co. v. Supermarket Equip. Corp., 340 U.S. 147, 153 (1950); 
see Graham v. John Deere Co., Graham v. John Deere Co., 
383 U.S. 1, 6 (1966) (“Congress may not authorize the issuance of patents whose effects are to remove existent 383 U.S. 1, 6 (1966) (“Congress may not authorize the issuance of patents whose effects are to remove existent 
knowledge from the public domain, or to restrict free access to materials already available.”). knowledge from the public domain, or to restrict free access to materials already available.”). 
33 35 U.S.C. § 103. 
33 35 U.S.C. § 103. 
34 34 
Id. Patent law frequently relies on the concept of a “person having ordinary skill in the art,” a “hypothetical person”  Patent law frequently relies on the concept of a “person having ordinary skill in the art,” a “hypothetical person” 
with a typical level of skill in the relevant technology who is “presumed to be aware of all the pertinent prior art” in the with a typical level of skill in the relevant technology who is “presumed to be aware of all the pertinent prior art” in the 
particular field. particular field. 
See Standard Oil Co. v. Am. Cyanamid Co., 774 F.2d 448, 454 (Fed. Cir. 1985).Standard Oil Co. v. Am. Cyanamid Co., 774 F.2d 448, 454 (Fed. Cir. 1985).
 
35 
35 
Graham, 383 U.S. at 17–18. , 383 U.S. at 17–18. 
36 KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 415–19 (2007). 36 KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 415–19 (2007). 
37 37 
Id. at 416.  at 416. 
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Utility Requirement 
An invention must also be 
An invention must also be 
useful to be patentable, which means that it must have a specific and to be patentable, which means that it must have a specific and 
substantial utility.38 The utility requirement derives from the Constitution’s command that patent substantial utility.38 The utility requirement derives from the Constitution’s command that patent 
laws exist to “promote the Progress of . . . laws exist to “promote the Progress of . . . 
useful Arts.”39 The constitutional purpose of patent law  Arts.”39 The constitutional purpose of patent law 
thus requires a “benefit derived by the public from an invention with substantial utility,” where thus requires a “benefit derived by the public from an invention with substantial utility,” where 
the “specific benefit exists in currently-available form.”40 The bar for utility is low, requiring only the “specific benefit exists in currently-available form.”40 The bar for utility is low, requiring only 
that the claimed invention have some “significant and presently available benefit to the public” that the claimed invention have some “significant and presently available benefit to the public” 
that “is not so vague as to be meaningless.”41 that “is not so vague as to be meaningless.”41 
Requirements for Specification and Claims  
Along with the four substantive requirements discussed above, the Patent Act imposes 
Along with the four substantive requirements discussed above, the Patent Act imposes 
requirements relating to the form of the patent application. These formal requirements pertain to requirements relating to the form of the patent application. These formal requirements pertain to 
two key sections of the patent application, known as the two key sections of the patent application, known as the 
claims and the  and the 
specification, which , which 
become part of the patent itself if the application is granted.  become part of the patent itself if the application is granted.  
Section 112 of the Patent Act requires that patents contain a “specification” that includes 
Section 112 of the Patent Act requires that patents contain a “specification” that includes 
a 
a 
written description of the invention, and of  of the invention, and of 
the manner and process of making and using 
it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to , in such full, clear, concise, and exact terms as to enable any person skilled in the art to 
. . . make  and  use  the  same,  and  shall  set  forth  . . . make  and  use  the  same,  and  shall  set  forth  
the  best  mode  contemplated  by   contemplated  by 
the inventor or joint inventor of carrying out the invention.42 the inventor or joint inventor of carrying out the invention.42 
This statutory language yields three basic disclosure requirements for patentability.43 First, to 
This statutory language yields three basic disclosure requirements for patentability.43 First, to 
satisfy the satisfy the 
written description requirement, the specification must “reasonably convey[] to those , the specification must “reasonably convey[] to those 
skilled in the art that the inventor had possession of the claimed subject matter as of the filing skilled in the art that the inventor had possession of the claimed subject matter as of the filing 
date” of the patent application.44 Second, to satisfy the date” of the patent application.44 Second, to satisfy the 
enablement requirement, the specification , the specification 
must contain enough information to teach a person skilled in the art how “to make and use the must contain enough information to teach a person skilled in the art how “to make and use the 
invention without undue experimentation.”45 Finally, to satisfy the invention without undue experimentation.”45 Finally, to satisfy the 
best mode requirement, the , the 
specification must show that the inventor “possessed a best mode for practicing the invention” at specification must show that the inventor “possessed a best mode for practicing the invention” at 
the time of the patent application, and disclose that preferred way of practicing the invention.46 the time of the patent application, and disclose that preferred way of practicing the invention.46 
These disclosure requirements ensure that the patent adequately discloses the invention to the These disclosure requirements ensure that the patent adequately discloses the invention to the 
public so that the public can use the invention after the patent term expires.47 public so that the public can use the invention after the patent term expires.47 
If granted, the patent’s legal scope is defined by the 
If granted, the patent’s legal scope is defined by the 
patent claims, which are words that , which are words that 
“particularly point[] out and distinctly claim[] the subject matter which the inventor . . . regards as “particularly point[] out and distinctly claim[] the subject matter which the inventor . . . regards as 
the invention.”48 In essence, while the specification explains the invention in a the invention.”48 In essence, while the specification explains the invention in a 
technical sense,  sense, 
 
 
38 Brenner v. Manson, 383 U.S. 519, 534–35 (1966); 
38 Brenner v. Manson, 383 U.S. 519, 534–35 (1966); 
In re Fisher, 421 F.3d 1365, 1371 (Fed. Cir. 2005).  Fisher, 421 F.3d 1365, 1371 (Fed. Cir. 2005). 
39 Stiftung v. Renishaw PLC, 945 F.2d 1173, 1180 (Fed. Cir. 1991) (citing 39 Stiftung v. Renishaw PLC, 945 F.2d 1173, 1180 (Fed. Cir. 1991) (citing 
Brenner, 383 U.S. at 528–29); , 383 U.S. at 528–29); 
see also  Graham, 383 U.S. at 5–6. , 383 U.S. at 5–6. 
40 
40 
Brenner, 383 U.S. at 534–35. , 383 U.S. at 534–35. 
41 41 
In re Fisher, 421 F.3d at 1371–72. , 421 F.3d at 1371–72. 
42 35 U.S.C. § 112(a) (emphasis added). 42 35 U.S.C. § 112(a) (emphasis added). 
43 43 
See Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 535 U.S. 722, 736 (2002); Ariad Pharms., Inc. v. Eli  Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 535 U.S. 722, 736 (2002); Ariad Pharms., Inc. v. Eli 
Lilly & Co., 598 F.3d 1336, 1344 (Fed. Cir. 2010) (en banc). Lilly & Co., 598 F.3d 1336, 1344 (Fed. Cir. 2010) (en banc). 
44 
44 
Ariad Pharms., 598 F.3d at 1351. , 598 F.3d at 1351. 
45 45 
In re Wands, 858 F.2d 731, 735 (Fed. Cir. 1988).  Wands, 858 F.2d 731, 735 (Fed. Cir. 1988). 
46 Eli Lilly & Co. v. Barr Lab’ys, Inc., 251 F.3d 955, 963 (Fed. Cir. 2001).46 Eli Lilly & Co. v. Barr Lab’ys, Inc., 251 F.3d 955, 963 (Fed. Cir. 2001).
 
47 47 
See Kewanee Oil Co. v. Bicron Corp., 416 U.S. 470, 480–81 (1974). Kewanee Oil Co. v. Bicron Corp., 416 U.S. 470, 480–81 (1974).
 
48 35 U.S.C. § 112(b). 48 35 U.S.C. § 112(b). 
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the claims set forth the patent’s 
the claims set forth the patent’s 
legal effect.49 Much as a deed may describe the boundaries of a  effect.49 Much as a deed may describe the boundaries of a 
tract of land, the claims define the “metes and bounds” of the patent right.50 Patent claims must be tract of land, the claims define the “metes and bounds” of the patent right.50 Patent claims must be 
sufficiently sufficiently 
definite to be valid—that is, when the claims are read in context, they must “inform,  to be valid—that is, when the claims are read in context, they must “inform, 
with reasonable certainty, those skilled in the art about the scope of the invention.”51 This with reasonable certainty, those skilled in the art about the scope of the invention.”51 This 
requirement is designed to give the public clear notice of what is and is not covered by the patent requirement is designed to give the public clear notice of what is and is not covered by the patent 
claims. claims. 
How Do Inventors Obtain a Patent? 
The process for receiving a patent begins with the filing of an application with USPTO.52 A The process for receiving a patent begins with the filing of an application with USPTO.52 A 
USPTO patent examiner then reviews the application for compliance with the legal requirements USPTO patent examiner then reviews the application for compliance with the legal requirements 
for receiving a patent.53 If the examiner determines that the application does not meet one of the for receiving a patent.53 If the examiner determines that the application does not meet one of the 
requirements, she will reject the application.54 The applicant may generally then amend the requirements, she will reject the application.54 The applicant may generally then amend the 
application in an effort to overcome the examiner’s rejection.55 Once the examiner determines application in an effort to overcome the examiner’s rejection.55 Once the examiner determines 
that an application meets all of the patentability requirements, she “allows” the application to that an application meets all of the patentability requirements, she “allows” the application to 
issue as a patent.56  issue as a patent.56  
Patent prosecution is the process of applying for a patent, addressing examiner concerns, and—if  is the process of applying for a patent, addressing examiner concerns, and—if 
successful—receiving the patent.57 USPTO examiners are generally not lawyers, but rather are successful—receiving the patent.57 USPTO examiners are generally not lawyers, but rather are 
subject specialists in the relevant science and/or technology area.58 Accordingly, USPTO issues subject specialists in the relevant science and/or technology area.58 Accordingly, USPTO issues 
the the 
Manual of Patent Examining Procedure (MPEP) to provide guidance for examiners and  (MPEP) to provide guidance for examiners and 
practitioners.59 practitioners.59 
How Do Courts Adjudicate Patent Rights? 
Patents are not self-enforcing: to obtain relief from infringement, the patentee must sue in court.60 Patents are not self-enforcing: to obtain relief from infringement, the patentee must sue in court.60 
Patent law is an area of exclusive federal jurisdiction,61 and the traditional forum for patent Patent law is an area of exclusive federal jurisdiction,61 and the traditional forum for patent 
 
 
49 
49 
See Ariad,,
 598 F.3d at 1347 (Fed. Cir. 2010); 598 F.3d at 1347 (Fed. Cir. 2010); 
In re Vamco Mach. & Tool, Inc., 752 F.2d 1564, 1577 n.5 (Fed. Cir.  Vamco Mach. & Tool, Inc., 752 F.2d 1564, 1577 n.5 (Fed. Cir. 
1985). 1985). 
50 Corning Glass Works v. Sumitomo Elec. U.S.A., Inc., 868 F.2d 1251, 1257 (Fed. Cir. 1989). 
50 Corning Glass Works v. Sumitomo Elec. U.S.A., Inc., 868 F.2d 1251, 1257 (Fed. Cir. 1989). 
51 Nautilus, Inc. v. Biosig Instruments, Inc., 572 U.S. 898, 901 (2014). 51 Nautilus, Inc. v. Biosig Instruments, Inc., 572 U.S. 898, 901 (2014). 
52 52 
See generally 35 U.S.C. § 111.  35 U.S.C. § 111. 
53 53 
See JAMES E. HAWES & FREDERIC M. DOUGLAS, PATENT APPLICATION PRACTICE § 2:4 (2020) (providing an overview JAMES E. HAWES & FREDERIC M. DOUGLAS, PATENT APPLICATION PRACTICE § 2:4 (2020) (providing an overview 
of the patent application process); USPTO, of the patent application process); USPTO, 
General Information Concerning Patents (Oct. 2015),  (Oct. 2015), 
https://www.uspto.gov/patents-getting-started/general-information-concerning-patents. https://www.uspto.gov/patents-getting-started/general-information-concerning-patents. 
54 HAWES & DOUGLAS, 
54 HAWES & DOUGLAS, 
supra  notenote 53, § § 14:2.  14:2. 
55 55 
Id. § 15.7−15.19.  § 15.7−15.19. 
56 56 
Id. § 21.1.  § 21.1. 
57 Nick Cornor, 57 Nick Cornor, 
Are Changes to the U.S. Patent System Objectively Killing Innovation?, 24 CURRENTS: J. INT’L ECON. , 24 CURRENTS: J. INT’L ECON. 
L. 87, 90 (2020) (“Patent prosecution refers to the process of applying for a patent.”). Although the foregoing L. 87, 90 (2020) (“Patent prosecution refers to the process of applying for a patent.”). Although the foregoing 
discussion provides a high-level overview of the process, patent prosecution is governed by specific laws and discussion provides a high-level overview of the process, patent prosecution is governed by specific laws and 
regulations, the detailed discussion of which could fill its own report. regulations, the detailed discussion of which could fill its own report. 
See generally HAWES & DOUGLAS,  HAWES & DOUGLAS, 
supra  notenote 53.  
58 Lital Helman, 
58 Lital Helman, 
Decentralized Patent System, 20 NEV. L.J. 67, 89 (2019) (“PTO examiners are not lawyers.”); , 20 NEV. L.J. 67, 89 (2019) (“PTO examiners are not lawyers.”); 
cf. Greg Greg 
Reilly, Reilly, 
Decoupling Patent Law, 97 B.U. L. REV. 551, 592 (2017) (“Inherently legal tasks—like parsing the wording of , 97 B.U. L. REV. 551, 592 (2017) (“Inherently legal tasks—like parsing the wording of 
documents, analogizing and distinguishing precedent, and applying canons of document interpretation—are better documents, analogizing and distinguishing precedent, and applying canons of document interpretation—are better 
suited for legally trained judges than legally limited patent examiners.”). suited for legally trained judges than legally limited patent examiners.”). 
59 59 
See USPTO, USPTO, 
Manual of Patent Examining Procedure (9th ed. July 2022), https://www.uspto.gov/web/offices/ (9th ed. July 2022), https://www.uspto.gov/web/offices/
pac/mpep/index.html [hereinafter MPEP]. pac/mpep/index.html [hereinafter MPEP]. 
60 35 U.S.C. § 281. 
60 35 U.S.C. § 281. 
61 28 U.S.C. § 1338. 61 28 U.S.C. § 1338. 
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disputes is federal district court.62 Although patent suits may be filed in any district court across 
disputes is federal district court.62 Although patent suits may be filed in any district court across 
the country with jurisdiction over the defendant and proper venue, all appealsthe country with jurisdiction over the defendant and proper venue, all appeals
 in patent cases are in patent cases are 
heard by a single specialized court, the U.S. Court of Appeals for the Federal Circuit (the Federal heard by a single specialized court, the U.S. Court of Appeals for the Federal Circuit (the Federal 
Circuit).63 Circuit).63 
Once accused of infringement in a district court case, the defendant may claim an “absence of 
Once accused of infringement in a district court case, the defendant may claim an “absence of 
liability” based on liability” based on 
noninfringement.64 In other words, the patentee may fail to prove that the .64 In other words, the patentee may fail to prove that the 
activities of the accused infringer fall within the scope of the patent claims.65  activities of the accused infringer fall within the scope of the patent claims.65  
Parties accused of patent infringement may also rely on several 
Parties accused of patent infringement may also rely on several 
affirmative defenses, which are , which are 
grounds on which the defendant—not the plaintiff—bears the burden of proof. First, although grounds on which the defendant—not the plaintiff—bears the burden of proof. First, although 
patents are subject to a presumption of validity, the accused infringer may assert that the patent is patents are subject to a presumption of validity, the accused infringer may assert that the patent is 
invalid.66 To prove invalidity, the accused infringer must show, by clear and convincing evidence, .66 To prove invalidity, the accused infringer must show, by clear and convincing evidence, 
that USPTO should not have granted the patent because the patent failed to meet the statutory that USPTO should not have granted the patent because the patent failed to meet the statutory 
requirements for patentability.67 Thus, for example, the accused infringer may argue that the requirements for patentability.67 Thus, for example, the accused infringer may argue that the 
invention lacks novelty, is obvious, or claims nonpatentable subject matter; that the patent fails to invention lacks novelty, is obvious, or claims nonpatentable subject matter; that the patent fails to 
enable the invention; or that the patent claims are indefinite.68  enable the invention; or that the patent claims are indefinite.68  
In addition, the accused infringer may argue the patent is 
In addition, the accused infringer may argue the patent is 
unenforceable based on the patent  based on the patent 
holder’s inequitable or illegal activities, such as obtaining the patent through fraud on USPTO.69 holder’s inequitable or illegal activities, such as obtaining the patent through fraud on USPTO.69 
All of these legal arguments are generally evaluated on a All of these legal arguments are generally evaluated on a 
claim-by-claim basis—that is, a court —that is, a court 
may find that some of the patent’s claims are valid but other claims are invalid, or that the may find that some of the patent’s claims are valid but other claims are invalid, or that the 
defendant infringes some of the patent’s claims but not others, for example. defendant infringes some of the patent’s claims but not others, for example. 
Both patent infringement and patent validity determinations turn in part on the meaning and scope 
Both patent infringement and patent validity determinations turn in part on the meaning and scope 
of a patent’s claims,70 which define the boundaries of the patentee’s intellectual property right. of a patent’s claims,70 which define the boundaries of the patentee’s intellectual property right. 
For instance, if a patent’s claims are interpreted broadly, it may be easier for the plaintiff to prove For instance, if a patent’s claims are interpreted broadly, it may be easier for the plaintiff to prove 
that the defendant’s products or activities infringe that patent. On the other hand, interpreting that the defendant’s products or activities infringe that patent. On the other hand, interpreting 
 
 
62 In 2023, roughly 3,108 patent lawsuits were filed in federal district courts. 
62 In 2023, roughly 3,108 patent lawsuits were filed in federal district courts. 
See 2023 Patent Dispute Report: Year in 
Review, UNIFIED PATENTS (Jan. 8, 2024), https://www.unifiedpatents.com/insights/2024/1/8/patent-dispute-report-, UNIFIED PATENTS (Jan. 8, 2024), https://www.unifiedpatents.com/insights/2024/1/8/patent-dispute-report-
2023-in-review. An additional forum for patent infringement disputes is the ITC, which has authority to conduct 2023-in-review. An additional forum for patent infringement disputes is the ITC, which has authority to conduct 
administrative trials into whether imported goods violate patent and other IP rights. administrative trials into whether imported goods violate patent and other IP rights. 
See 19 U.S.C. § 1337. The ITC 19 U.S.C. § 1337. The ITC 
may issue exclusion orders to stop such goods from entering the United States. may issue exclusion orders to stop such goods from entering the United States. 
See CRS In Focus IF12295, CRS In Focus IF12295, 
An 
Introduction to Section 337 Intellectual Property Litigation at the U.S. International Trade Commission, by , by 
Christopher T. Zirpoli (2024). The ITC typically initiates several dozen Section 337 investigations per year. Christopher T. Zirpoli (2024). The ITC typically initiates several dozen Section 337 investigations per year. 
See  Section 
337 Statistics: Number of New, Completed, and Active Investigations by Fiscal Year, ITC (last updated Oct. 12, 2023), , ITC (last updated Oct. 12, 2023), 
https://www.usitc.gov/intellectual_property/337_statistics_number_new_completed_and_active.htm (reporting fifty-https://www.usitc.gov/intellectual_property/337_statistics_number_new_completed_and_active.htm (reporting fifty-
five new complaints in Fiscal Year 2023). five new complaints in Fiscal Year 2023). 
63 28 U.S.C. § 1295(a)(1). 
63 28 U.S.C. § 1295(a)(1). 
 
64 35 U.S.C. § 282(b)(1). 64 35 U.S.C. § 282(b)(1). 
65 To prove direct infringement, the plaintiff must show that each element contained in a patent claim is practiced by 65 To prove direct infringement, the plaintiff must show that each element contained in a patent claim is practiced by 
the alleged infringer, either literally or by an equivalent. Warner-Jenkinson Co. v. Hilton Davis Chem. Co., 520 U.S. the alleged infringer, either literally or by an equivalent. Warner-Jenkinson Co. v. Hilton Davis Chem. Co., 520 U.S. 
17, 29–30 (1997). 17, 29–30 (1997). 
66 35 U.S.C. § 282(a)–(b). 
66 35 U.S.C. § 282(a)–(b). 
67 67 
Id. § 282(b)(2)–(3); Microsoft Corp. v. i4i LP, 564 U.S. 91, 95–96 (2011).  § 282(b)(2)–(3); Microsoft Corp. v. i4i LP, 564 U.S. 91, 95–96 (2011). 
68 35 U.S.C. §§ 101, 102–103, 112, 282(b)(2)–(3). 68 35 U.S.C. §§ 101, 102–103, 112, 282(b)(2)–(3). 
69 Therasense, Inc. v. Becton, Dickinson & Co., 649 F.3d 1276, 1285, 1290–91 (Fed. Cir. 2011) (en banc). 69 Therasense, Inc. v. Becton, Dickinson & Co., 649 F.3d 1276, 1285, 1290–91 (Fed. Cir. 2011) (en banc). 
70 MPHJ Tech. Invs., LLC v. Ricoh Ams. Corp., 847 F.3d 1363, 1364 (Fed. Cir. 2017) (“[T]he first step in any validity 70 MPHJ Tech. Invs., LLC v. Ricoh Ams. Corp., 847 F.3d 1363, 1364 (Fed. Cir. 2017) (“[T]he first step in any validity 
analysis is to construe the claims of the invention to determine the subject matter for which patent protection is sought.” analysis is to construe the claims of the invention to determine the subject matter for which patent protection is sought.” 
(quoting Smiths Indus. Med. Sys., Inc. v. Vital Signs, Inc., 183 F.3d 1347, 1353 (Fed. Cir. 1999))); Nazomi Commc’ns, (quoting Smiths Indus. Med. Sys., Inc. v. Vital Signs, Inc., 183 F.3d 1347, 1353 (Fed. Cir. 1999))); Nazomi Commc’ns, 
Inc. v. Nokia Corp., 739 F.3d 1339, 1343 (Fed. Cir. 2014) (“The first step of the infringement analysis is claim Inc. v. Nokia Corp., 739 F.3d 1339, 1343 (Fed. Cir. 2014) (“The first step of the infringement analysis is claim 
construction . . . .”); construction . . . .”); 
see also TVIIM, LLC v. McAfee, Inc., 851 F.3d 1356, 1362 (Fed. Cir. 2017) (“Claim terms must TVIIM, LLC v. McAfee, Inc., 851 F.3d 1356, 1362 (Fed. Cir. 2017) (“Claim terms must 
be construed the same way for the purpose of determining invalidity and infringement.”). be construed the same way for the purpose of determining invalidity and infringement.”). 
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claims broadly may make it easier for the defendant to show that the claims are invalid because 
claims broadly may make it easier for the defendant to show that the claims are invalid because 
they were anticipated or obvious in light of prior art. When the parties dispute how patent claims they were anticipated or obvious in light of prior art. When the parties dispute how patent claims 
should be interpreted, the judge must decide how to construe the disputed claim terms.71 The should be interpreted, the judge must decide how to construe the disputed claim terms.71 The 
process for determining the meaning of a disputed patent claim term is referred to as process for determining the meaning of a disputed patent claim term is referred to as 
claim 
construction.72 While claim construction is a question of law decided by the judge,73 the ultimate .72 While claim construction is a question of law decided by the judge,73 the ultimate 
issue of whether the accused product(s) infringe the patent claims, as construed by the judge, is a issue of whether the accused product(s) infringe the patent claims, as construed by the judge, is a 
question of fact generally tried to a jury.74 question of fact generally tried to a jury.74 
What Was USPTO’s Role in Patent Adjudication Prior to the AIA? 
In addition to asserting invalidity as an affirmative defense to a patent infringement lawsuit in In addition to asserting invalidity as an affirmative defense to a patent infringement lawsuit in 
district court, a person may petition to invalidate an issued patent in various administrative district court, a person may petition to invalidate an issued patent in various administrative 
proceedings known as proceedings known as 
post-grant proceedings, which are administered by USPTO.75 Before the , which are administered by USPTO.75 Before the 
AIA was enacted, the available post-grant proceedings included ex parte reexamination and inter AIA was enacted, the available post-grant proceedings included ex parte reexamination and inter 
partes reexamination.  partes reexamination.  
Ex parte reexamination, the longest-standing post-grant proceeding, allows “[a]ny person at any 
Ex parte reexamination, the longest-standing post-grant proceeding, allows “[a]ny person at any 
time” (including the patent owner herself) to request that USPTO reexamine an issued patent.76 time” (including the patent owner herself) to request that USPTO reexamine an issued patent.76 
The request must be based on “patents or printed publications which that person believes to have The request must be based on “patents or printed publications which that person believes to have 
a bearing on the patentability of any claim of a particular patent.”77 If the USPTO Director a bearing on the patentability of any claim of a particular patent.”77 If the USPTO Director 
determines that the request raises “a substantial new question of patentability affecting any claim determines that the request raises “a substantial new question of patentability affecting any claim 
of the patent,” then she may institute an ex parte reexamination.78 If a reexamination is initiated, it of the patent,” then she may institute an ex parte reexamination.78 If a reexamination is initiated, it 
proceeds in the same manner as the initial patent examination; in other words, the examiner may proceeds in the same manner as the initial patent examination; in other words, the examiner may 
reject the claims on the basis of the new prior art, the applicant may amend the claims, et cetera.79 reject the claims on the basis of the new prior art, the applicant may amend the claims, et cetera.79 
Claim terms are given their broadest reasonable construction consistent with the specification (as Claim terms are given their broadest reasonable construction consistent with the specification (as 
in the initial examination).80 The person who sought reexamination, however, is not involved in in the initial examination).80 The person who sought reexamination, however, is not involved in 
the process once USPTO decides to initiate reexamination. the process once USPTO decides to initiate reexamination. 
 
 
71 Markman v. Westview Instruments, Inc., 517 U.S. 370, 372 (1996) (“We hold that the construction of a patent, 
71 Markman v. Westview Instruments, Inc., 517 U.S. 370, 372 (1996) (“We hold that the construction of a patent, 
including terms of art within its claim, is exclusively within the province of the court.”). including terms of art within its claim, is exclusively within the province of the court.”). 
72 Netword, LLC v. Centraal Corp., 242 F.3d 1347, 1352 (Fed. Cir. 2001) (“‘Claim construction’ is the judicial 72 Netword, LLC v. Centraal Corp., 242 F.3d 1347, 1352 (Fed. Cir. 2001) (“‘Claim construction’ is the judicial 
statement of what is and is not covered by the technical terms and other words of the claims.”); statement of what is and is not covered by the technical terms and other words of the claims.”); 
see also Abbott Lab’ys  Abbott Lab’ys 
v. Sandoz, Inc., 544 F.3d 1341, 1358 (Fed. Cir. 2008) (“The first step in most infringement suits is the procedure called v. Sandoz, Inc., 544 F.3d 1341, 1358 (Fed. Cir. 2008) (“The first step in most infringement suits is the procedure called 
‘claim construction,’ where the scope of the claim is defined by the court.”); Pall Corp. v. Hemasure, Inc., 181 F.3d ‘claim construction,’ where the scope of the claim is defined by the court.”); Pall Corp. v. Hemasure, Inc., 181 F.3d 
1305, 1308 (Fed. Cir. 1999) (“Analysis of patent infringement starts with ‘construction’ of the claim, whereby the court 1305, 1308 (Fed. Cir. 1999) (“Analysis of patent infringement starts with ‘construction’ of the claim, whereby the court 
establishes the scope and limits of the claim, interprets any technical or other terms whose meaning is at issue, and establishes the scope and limits of the claim, interprets any technical or other terms whose meaning is at issue, and 
thereby defines the claim with greater precision than had the patentee.”). thereby defines the claim with greater precision than had the patentee.”). 
73 73 
See Markman, 517 U.S. at 372. , 517 U.S. at 372. 
74 74 
See Apple Inc. v. Samsung Elecs. Co., 839 F.3d 1034, 1040 (Fed. Cir. 2016) (en banc) (reviewing jury verdict of Apple Inc. v. Samsung Elecs. Co., 839 F.3d 1034, 1040 (Fed. Cir. 2016) (en banc) (reviewing jury verdict of 
infringement). infringement). 
75 Although the terminology is different, there is no practical difference between a district court invalidating a claim 
75 Although the terminology is different, there is no practical difference between a district court invalidating a claim 
during litigation and USPTO cancelling a claim following an administrative proceeding. The result is the same: the during litigation and USPTO cancelling a claim following an administrative proceeding. The result is the same: the 
patent can no longer be enforced. patent can no longer be enforced. 
76 35 U.S.C. § 302. 
76 35 U.S.C. § 302. 
77 77 
Id. § 301(a)(1).  § 301(a)(1). 
78 78 
Id. § 303(a). The USPTO Director may also determine whether a substantial new question of patentability exists on  § 303(a). The USPTO Director may also determine whether a substantial new question of patentability exists on 
her own initiative. her own initiative. 
Id.    
79 
79 
Id. § 305. For more detail regarding initial examination, see Hickey,  § 305. For more detail regarding initial examination, see Hickey, 
supra no no
te 4, at 8–9.  at 8–9. 
80 80 
In re Man Mach. Interface Techs. LLC, 822 F.3d 1282, 1286 (Fed. Cir. 2016) (“In reexamination, claims are given  Man Mach. Interface Techs. LLC, 822 F.3d 1282, 1286 (Fed. Cir. 2016) (“In reexamination, claims are given 
their broadest reasonable interpretation . . . consistent with the specification.”). their broadest reasonable interpretation . . . consistent with the specification.”). 
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In 1999, inter partes reexamination was added as an available post-grant proceeding for persons 
In 1999, inter partes reexamination was added as an available post-grant proceeding for persons 
to challenge granted patents.81 Inter partes reexamination provided third-party requesters the to challenge granted patents.81 Inter partes reexamination provided third-party requesters the 
ability to participate to a limited extent in a reexamination through comments and declarations ability to participate to a limited extent in a reexamination through comments and declarations 
submitted during the reexamination proceedings.82 Third-party requestors who sought inter partes submitted during the reexamination proceedings.82 Third-party requestors who sought inter partes 
reexamination were later estopped from alleging that a patent was invalid based on any grounds reexamination were later estopped from alleging that a patent was invalid based on any grounds 
that could have been raised in the reexamination.83  that could have been raised in the reexamination.83  
The AIA eliminated inter partes reexamination and created two currently available adversarial 
The AIA eliminated inter partes reexamination and created two currently available adversarial 
post-grant proceedings—known as inter partes review and post-grant review—and established post-grant proceedings—known as inter partes review and post-grant review—and established 
PTAB to administer them. The following sections discuss in depth the AIA, PTAB, and the new PTAB to administer them. The following sections discuss in depth the AIA, PTAB, and the new 
post-grant proceedings. post-grant proceedings. 
Overview of the America Invents Act and PTAB 
In 2011, Congress passed the AIA, a major reform of U.S. patent law. Among the most important In 2011, Congress passed the AIA, a major reform of U.S. patent law. Among the most important 
changes made in the AIA were the creation of PTAB and the new post-grant proceedings for changes made in the AIA were the creation of PTAB and the new post-grant proceedings for 
PTAB to administer. This section provides an overview of the key provisions of the AIA and the PTAB to administer. This section provides an overview of the key provisions of the AIA and the 
administrative structure it established for PTAB.  administrative structure it established for PTAB.  
The AIA’s Key Changes to Patent Law 
Under the AIA, PTAB replaced a body known as the Board of Patent Appeals and Under the AIA, PTAB replaced a body known as the Board of Patent Appeals and 
Interferences (BPAI), which ceased to exist when PTAB began operations in 2012.84 PTAB took Interferences (BPAI), which ceased to exist when PTAB began operations in 2012.84 PTAB took 
over BPAI’s responsibility for hearing appeals from USPTO rejections of patent applications.85 over BPAI’s responsibility for hearing appeals from USPTO rejections of patent applications.85 
PTAB also took over BPAI’s responsibility for hearing appeals from rejections of patent owners’ PTAB also took over BPAI’s responsibility for hearing appeals from rejections of patent owners’ 
claims in ex parte reexaminations.86  claims in ex parte reexaminations.86  
The AIA replaced inter partes reexamination with two new administrative proceedings—inter 
The AIA replaced inter partes reexamination with two new administrative proceedings—inter 
partes review (IPR) and post-grant review (PGR)—administered by PTAB. The AIA also created partes review (IPR) and post-grant review (PGR)—administered by PTAB. The AIA also created 
a transitional program to challenge covered business method (CBM) patents, which expired in a transitional program to challenge covered business method (CBM) patents, which expired in 
2020. These proceedings are discussed in detail below.87  2020. These proceedings are discussed in detail below.87  
In addition, the AIA effected a major change to U.S. patent law with respect to 
In addition, the AIA effected a major change to U.S. patent law with respect to 
priority, or who is , or who is 
entitled to a patent when different people claim to have invented the same thing at around the entitled to a patent when different people claim to have invented the same thing at around the 
same time.88 Previously, the first person to same time.88 Previously, the first person to 
invent a particular invention was generally given  a particular invention was generally given 
priority in obtaining a patent when two different people filed patent applications on the same priority in obtaining a patent when two different people filed patent applications on the same 
invention.89 The AIA provides that for applications filed on or after March 16, 2013, the first invention.89 The AIA provides that for applications filed on or after March 16, 2013, the first 
 
 
81 American Inventors Protection Act of 1999, Pub. L. No. 106-113. 
81 American Inventors Protection Act of 1999, Pub. L. No. 106-113. 
82 MPEP, 82 MPEP, 
supra  notenote 59, §§ 2609, 2654.  §§ 2609, 2654.  
83 35 U.S.C. § 315(c) (2011).  83 35 U.S.C. § 315(c) (2011).  
84 U.S. GOV’T ACCOUNTABILITY OFF., GAO-22-106121, PATENT TRIAL AND APPEAL BOARD: PRELIMINARY 84 U.S. GOV’T ACCOUNTABILITY OFF., GAO-22-106121, PATENT TRIAL AND APPEAL BOARD: PRELIMINARY 
OBSERVATIONS ON OVERSIGHT OF JUDICIAL DECISIONMAKING 1 n.1 (2022). OBSERVATIONS ON OVERSIGHT OF JUDICIAL DECISIONMAKING 1 n.1 (2022). 
85 35 U.S.C. § 134(a) (allowing applicant to appeal to PTAB after “claim[] has been twice rejected”). 
85 35 U.S.C. § 134(a) (allowing applicant to appeal to PTAB after “claim[] has been twice rejected”). 
86 35 U.S.C. § 134(b) (allowing owner to appeal to PTAB from “final rejection” in a reexamination). BPAI had also 86 35 U.S.C. § 134(b) (allowing owner to appeal to PTAB from “final rejection” in a reexamination). BPAI had also 
overseen appeals from inter partes reexamination proceedings.  overseen appeals from inter partes reexamination proceedings.  
87 
87 
See infra  “PTAB Post-Grant Proceedings.”  88 88 
See SNIPR Techs. Ltd. v. Rockefeller Univ., 72 F.4th 1372, 1374 (Fed. Cir. 2023) (“‘Patent priority’ establishes who  SNIPR Techs. Ltd. v. Rockefeller Univ., 72 F.4th 1372, 1374 (Fed. Cir. 2023) (“‘Patent priority’ establishes who 
is entitled to a patent on a particular invention claimed by different parties.”). is entitled to a patent on a particular invention claimed by different parties.”). 
89 Leahy-Smith America Invents Act, Pub. L. No. 112-29, § 3(n)–(o), 125 Stat. 284, 293 (2011).89 Leahy-Smith America Invents Act, Pub. L. No. 112-29, § 3(n)–(o), 125 Stat. 284, 293 (2011).
 
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inventor to 
inventor to 
file an application with USPTO is regarded as the inventor.90 The AIA thus changed  an application with USPTO is regarded as the inventor.90 The AIA thus changed 
the United States from a the United States from a 
first-to-invent to a  to a 
first-to-file jurisdiction,91 consistent with the rest of jurisdiction,91 consistent with the rest of 
the world.92 In addition to international uniformity, Congress sought to make priority the world.92 In addition to international uniformity, Congress sought to make priority 
determinations more “objective and simple” by changing to a first-to-file system.93 (Generally determinations more “objective and simple” by changing to a first-to-file system.93 (Generally 
speaking, it is simpler to determine when a person filed a patent application than when a person speaking, it is simpler to determine when a person filed a patent application than when a person 
conceived of a particular idea and reduced it to practice.) conceived of a particular idea and reduced it to practice.) 
To match the change to a first-to-file patent system, the AIA overhauled proceedings for 
To match the change to a first-to-file patent system, the AIA overhauled proceedings for 
contesting priority. Previously, if a person claimed to have invented something earlier than the contesting priority. Previously, if a person claimed to have invented something earlier than the 
patent applicant, that person could contest ownership of the patent via a challenge known as an patent applicant, that person could contest ownership of the patent via a challenge known as an 
interference, which could be asserted in administrative proceedings decided by BPAI or in district , which could be asserted in administrative proceedings decided by BPAI or in district 
court.94 The AIA left interferences in place for patents filed prior to March 16, 2013 (i.e., under court.94 The AIA left interferences in place for patents filed prior to March 16, 2013 (i.e., under 
the first-to-invent regime),95 and transferred responsibility for those proceedings to PTAB.96 For the first-to-invent regime),95 and transferred responsibility for those proceedings to PTAB.96 For 
patents filed on or after March 16, 2013, interference proceedings “are no longer necessary patents filed on or after March 16, 2013, interference proceedings “are no longer necessary 
because it is now the first filer—not the first inventor—who has priority and is entitled to a because it is now the first filer—not the first inventor—who has priority and is entitled to a 
patent.”97  patent.”97  
For patents filed on or after March 16, 2016, the AIA replaced interference with 
For patents filed on or after March 16, 2016, the AIA replaced interference with 
derivation, a , a 
challenge that may be asserted in proceedings decided by PTAB or in district court litigation.98 challenge that may be asserted in proceedings decided by PTAB or in district court litigation.98 
Whereas interference allowed a challenger to take priority over a patent by showing that the Whereas interference allowed a challenger to take priority over a patent by showing that the 
challenger had invented the claimed subject matter before the patentee, derivation requires the challenger had invented the claimed subject matter before the patentee, derivation requires the 
challenger to show that an earlier patent filer derived the invention from the challenger (i.e., the challenger to show that an earlier patent filer derived the invention from the challenger (i.e., the 
patentee took the idea from the challenger as opposed to inventing it independently).99 Derivation patentee took the idea from the challenger as opposed to inventing it independently).99 Derivation 
is used infrequently, with one survey counting fewer than two dozen derivation petitions filed at is used infrequently, with one survey counting fewer than two dozen derivation petitions filed at 
USPTO between 2013 and 2022.100 USPTO between 2013 and 2022.100 
PTAB’s Structure 
The AIA provides that PTAB consists of the USPTO Director and Deputy Director, the The AIA provides that PTAB consists of the USPTO Director and Deputy Director, the 
Commissioner for Patents, the Commissioner of Trademarks, and an unspecified number of Commissioner for Patents, the Commissioner of Trademarks, and an unspecified number of 
 
 
90 
90 
Id.; ; 
see also 35 U.S.C. § 102.  35 U.S.C. § 102. 
91 91 
See  SNIPR Techs., 72 F.4th at 1373. , 72 F.4th at 1373. 
92 92 
See id. at 1375 (“The U.S. was the last remaining country in the world to use a first-to-invent system.”).  at 1375 (“The U.S. was the last remaining country in the world to use a first-to-invent system.”). 
93 93 
Id. at 1374. Consistent with the new first-to-file system, the AIA amended the definitions of prior art and  at 1374. Consistent with the new first-to-file system, the AIA amended the definitions of prior art and 
obviousness so that both would be assessed as of the filing date rather than the time of invention. obviousness so that both would be assessed as of the filing date rather than the time of invention. 
See id. at 1375.  at 1375. 
94 
94 
See id. at 1375.  at 1375. 
95 95 
See id. at 1376; Biogen MA, Inc. v. Japanese Found. for Cancer Rsch., 785 F.3d 648, 655 (Fed. Cir. 2015) (noting  at 1376; Biogen MA, Inc. v. Japanese Found. for Cancer Rsch., 785 F.3d 648, 655 (Fed. Cir. 2015) (noting 
“interference proceedings are to continue with respect to . . . applications filed before March 16, 2013”).  “interference proceedings are to continue with respect to . . . applications filed before March 16, 2013”).  
96 The AIA also left interference in place for patents that contain at least one claim each with pre- and post-March 16, 96 The AIA also left interference in place for patents that contain at least one claim each with pre- and post-March 16, 
2013, effective filing dates. 2013, effective filing dates. 
See  SNIPR Techs., 72 F.4th at 1376. In , 72 F.4th at 1376. In 
SNIPR Techs., the Federal Circuit held that “pure , the Federal Circuit held that “pure 
AIA patents” with no claims having pre-March 16, 2013, filing dates may not be subjected to interference, including AIA patents” with no claims having pre-March 16, 2013, filing dates may not be subjected to interference, including 
where the alleged basis for prior inventorship is a pre-AIA patent. where the alleged basis for prior inventorship is a pre-AIA patent. 
See id. at 1374.   at 1374.  
97
97
 Id. at 1374.  at 1374. 
98 98 
See 35 U.S.C. § 135 (derivation proceedings decided by PTAB), § 291 (derivation asserted in district court);  35 U.S.C. § 135 (derivation proceedings decided by PTAB), § 291 (derivation asserted in district court); 
SNIPR 
Techs., 72 F.4th at 1375–76 (“AIA . . . repealed interferences in pre-AIA §§ 135 and 291 . . . .”). , 72 F.4th at 1375–76 (“AIA . . . repealed interferences in pre-AIA §§ 135 and 291 . . . .”). 
99 See 
99 See 
SNIPR Techs., 72 F.4th at 1376 (“Whereas interference proceedings determined who was the first inventor, , 72 F.4th at 1376 (“Whereas interference proceedings determined who was the first inventor, 
derivation proceedings determine whether the earlier filer had derived the claimed invention from a later filer.”). derivation proceedings determine whether the earlier filer had derived the claimed invention from a later filer.”). 
100 100 
See Barbra Clarke McCurdy et al., Barbra Clarke McCurdy et al., 
Spotted: The Rare AIA Derivation Proceeding!, FINNEGAN (April 22, 2022), , FINNEGAN (April 22, 2022), 
https://www.finnegan.com/en/insights/blogs/at-the-ptab-blog/spotted-the-rare-aia-derivation-proceeding.html. https://www.finnegan.com/en/insights/blogs/at-the-ptab-blog/spotted-the-rare-aia-derivation-proceeding.html. 
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administrative patent judges (APJs).101 Currently, PTAB employs more than 200 APJs.102 PTAB is 
administrative patent judges (APJs).101 Currently, PTAB employs more than 200 APJs.102 PTAB is 
divided into a Trial Division and an Appeals Division. The Trial Division administers post-grant divided into a Trial Division and an Appeals Division. The Trial Division administers post-grant 
proceedings created by the AIA, while the Appeals Division hears appeals of patent prosecution proceedings created by the AIA, while the Appeals Division hears appeals of patent prosecution 
decisions.  decisions.  
The Secretary of Commerce, in consultation with the USPTO Director, appoints the APJs to serve 
The Secretary of Commerce, in consultation with the USPTO Director, appoints the APJs to serve 
on PTAB.103 The AIA requires that APJs be “persons of competent legal knowledge and scientific on PTAB.103 The AIA requires that APJs be “persons of competent legal knowledge and scientific 
ability.”104 The Director, who is appointed by the President with advice and consent of the Senate, ability.”104 The Director, who is appointed by the President with advice and consent of the Senate, 
is a member of PTAB and maintains a degree of authority over the APJs.105 The AIA gives the is a member of PTAB and maintains a degree of authority over the APJs.105 The AIA gives the 
Director authority to select the three-member APJ panels who decide IPRs106 and to issue Director authority to select the three-member APJ panels who decide IPRs106 and to issue 
regulations governing the conduct of PTAB proceedings,107 although in practice the Director has regulations governing the conduct of PTAB proceedings,107 although in practice the Director has 
delegated panel selection to a Chief Judge.108 The AIA also gives the Director authority to delegated panel selection to a Chief Judge.108 The AIA also gives the Director authority to 
designate selected written decisions as precedential and thus binding on future panels of APJs.109 designate selected written decisions as precedential and thus binding on future panels of APJs.109 
APJs cannot be removed without cause.110 APJs cannot be removed without cause.110 
PTAB Post-Grant Proceedings 
As noted above, the AIA charged PTAB with administering three new types of post-grant As noted above, the AIA charged PTAB with administering three new types of post-grant 
proceedings for challenging the validity of patents previously issued by USPTO. One of these proceedings for challenging the validity of patents previously issued by USPTO. One of these 
proceedings, CBM review, sunset in 2020 pursuant to the AIA. The other two—IPR and PGR—proceedings, CBM review, sunset in 2020 pursuant to the AIA. The other two—IPR and PGR—
have no sunset provision and are regularly used. have no sunset provision and are regularly used. 
This section provides an overview and comparison of IPR, PGR, and CBM reviews. The 
This section provides an overview and comparison of IPR, PGR, and CBM reviews. The 
discussion focuses principally on IPR, which has been both the most used type of PTAB discussion focuses principally on IPR, which has been both the most used type of PTAB 
proceeding and the target of many current reform efforts, which are discussed in the final section proceeding and the target of many current reform efforts, which are discussed in the final section 
of the report.111  of the report.111  
Inter Partes Review 
IPR is the most-used type of post-grant proceeding introduced by the AIA by an overwhelming IPR is the most-used type of post-grant proceeding introduced by the AIA by an overwhelming 
margin.112 This section discusses the statutory requirements for filing an IPR, PTAB’s discretion margin.112 This section discusses the statutory requirements for filing an IPR, PTAB’s discretion 
whether to institute IPRs, and the IPR process.  whether to institute IPRs, and the IPR process.  
 
 
101 35 U.S.C. § 6(a). 
101 35 U.S.C. § 6(a). 
102 U.S. GOV’T ACCOUNTABILITY OFF., GAO-23-105336, PATENT TRIAL AND APPEAL BOARD: INCREASED 102 U.S. GOV’T ACCOUNTABILITY OFF., GAO-23-105336, PATENT TRIAL AND APPEAL BOARD: INCREASED 
TRANSPARENCY NEEDED IN OVERSIGHT OF JUDICIAL DECISION-MAKING 14 (2022), at 5 [hereinafter GAO PTAB TRANSPARENCY NEEDED IN OVERSIGHT OF JUDICIAL DECISION-MAKING 14 (2022), at 5 [hereinafter GAO PTAB 
REPORT]. REPORT]. 
103 35 U.S.C. § 6(a). 
103 35 U.S.C. § 6(a). 
104 104 
Id.  105 105 
See  id.  106 106 
Id. § 6(c).  § 6(c). 
107 107 
Id. § 6(b)(2).  § 6(b)(2). 
108 USPTO, PATENT TRIAL AND APPEAL BOARD: STANDARD OPERATING PROCEDURE 1 (rev. 15), 108 USPTO, PATENT TRIAL AND APPEAL BOARD: STANDARD OPERATING PROCEDURE 1 (rev. 15), 
https://www.uspto.gov/sites/default/files/documents/SOP%201%20R15%20FINAL.pdf [hereinafter SOP 1]. https://www.uspto.gov/sites/default/files/documents/SOP%201%20R15%20FINAL.pdf [hereinafter SOP 1]. 
109 
109 
See USPTO, PATENT AND TRIAL APPEAL BOARD: STANDARD OPERATING PROCEDURE 2 (rev. 11) (July 24, 2023), USPTO, PATENT AND TRIAL APPEAL BOARD: STANDARD OPERATING PROCEDURE 2 (rev. 11) (July 24, 2023), 
https://www.uspto.gov/sites/default/files/documents/20230724_ptab_sop2_rev11_.pdf.  https://www.uspto.gov/sites/default/files/documents/20230724_ptab_sop2_rev11_.pdf.  
110 35 U.S.C. § 3(c); 5 U.S.C. § 7513(a); 
110 35 U.S.C. § 3(c); 5 U.S.C. § 7513(a); 
see also United States v. Arthrex, Inc., 594 U.S. 1, 16–17 (2021).  United States v. Arthrex, Inc., 594 U.S. 1, 16–17 (2021).  
111 111 
See infra “Current Debates and Proposed Reforms.”  112 112 
See USPTO, PTAB TRIAL STATISTICS: FY23 END OF YEAR OUTCOME ROUNDUP—IPR, PGR 3, USPTO, PTAB TRIAL STATISTICS: FY23 END OF YEAR OUTCOME ROUNDUP—IPR, PGR 3, 
https://www.uspto.gov/sites/default/files/documents/ptab_aia_fy2023__roundup.pdf (last visited Mar. 28, 2024) https://www.uspto.gov/sites/default/files/documents/ptab_aia_fy2023__roundup.pdf (last visited Mar. 28, 2024) 
[hereinafter PTAB FY23 STATISTICS]. [hereinafter PTAB FY23 STATISTICS]. 
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Standing, Timing, and Grounds to Petition for IPR 
Any person other than the patent owner may file a petition requesting that PTAB institute (i.e., 
Any person other than the patent owner may file a petition requesting that PTAB institute (i.e., 
proceed with) an IPR.113 An IPR petition may be filed at any time starting nine months after the proceed with) an IPR.113 An IPR petition may be filed at any time starting nine months after the 
patent issues through the time the patent expires.114 If the petitioner or their “real party in patent issues through the time the patent expires.114 If the petitioner or their “real party in 
interest[] or privy” is sued for infringement of the patent, the petitioner may not file the petition interest[] or privy” is sued for infringement of the patent, the petitioner may not file the petition 
any later than one year after they are served with the infringement complaint.115 any later than one year after they are served with the infringement complaint.115 
An IPR petition may challenge the validity of patent claim on only two bases—anticipation (35 
An IPR petition may challenge the validity of patent claim on only two bases—anticipation (35 
U.S.C. § 102) or obviousness (35 U.S.C. § 103).116 It may not challenge patentability for other U.S.C. § 102) or obviousness (35 U.S.C. § 103).116 It may not challenge patentability for other 
reasons, such as whether the patent claims eligible subject matter (35 U.S.C. § 101) or is not reasons, such as whether the patent claims eligible subject matter (35 U.S.C. § 101) or is not 
enabled (35 U.S.C. § 112). The IPR petition may rely only on prior art patents or printed enabled (35 U.S.C. § 112). The IPR petition may rely only on prior art patents or printed 
publications.117 Other forms of prior art, such as public uses or sales of the claimed invention, publications.117 Other forms of prior art, such as public uses or sales of the claimed invention, 
cannot be a basis for IPR.118  cannot be a basis for IPR.118  
An IPR petition must also meet a number of procedural requirements. For example, the petitioner 
An IPR petition must also meet a number of procedural requirements. For example, the petitioner 
must identify all real parties-in-interest; identify the challenged patent claims and the grounds for must identify all real parties-in-interest; identify the challenged patent claims and the grounds for 
the challenge “with particularity”; and pay a fee set by USPTO.119 the challenge “with particularity”; and pay a fee set by USPTO.119 
Discretionary Institution of IPR 
The AIA makes the USPTO Director responsible for deciding whether or not to institute an 
The AIA makes the USPTO Director responsible for deciding whether or not to institute an 
IPR.120 The Director is charged with making this decision based on the challenger’s petition as IPR.120 The Director is charged with making this decision based on the challenger’s petition as 
well as an optional preliminary response that the patent owner may choose to file within three well as an optional preliminary response that the patent owner may choose to file within three 
months of the petition.121 The Director must determine whether to institute the IPR within three months of the petition.121 The Director must determine whether to institute the IPR within three 
months of receiving the preliminary response (or three months after the last date on which such a months of receiving the preliminary response (or three months after the last date on which such a 
response could be filed).122 The Director has delegated all IPR institution decisions to PTAB.123 response could be filed).122 The Director has delegated all IPR institution decisions to PTAB.123 
When an IPR petition is filed, a panel of three APJs is assigned to the case, and it is this panel that When an IPR petition is filed, a panel of three APJs is assigned to the case, and it is this panel that 
makes the institution decision.124 Thus, references to the “Director” in the provisions of the AIA makes the institution decision.124 Thus, references to the “Director” in the provisions of the AIA 
regarding institution now refer, in practice, to a PTAB panel of three APJs. regarding institution now refer, in practice, to a PTAB panel of three APJs. 
The AIA does not permit PTAB to institute an IPR unless it determines that the petition and any 
The AIA does not permit PTAB to institute an IPR unless it determines that the petition and any 
preliminary response “shows that there is a reasonable likelihood that the petitioner would prevail preliminary response “shows that there is a reasonable likelihood that the petitioner would prevail 
with respect to at least 1 of the claims challenged in the petition.”125 Nonetheless, the AIA does with respect to at least 1 of the claims challenged in the petition.”125 Nonetheless, the AIA does 
not not 
require PTAB to institute an IPR if this threshold is satisfied, and it provides that “[t]he  PTAB to institute an IPR if this threshold is satisfied, and it provides that “[t]he 
 
 
113 35 U.S.C. § 311(a). 
113 35 U.S.C. § 311(a). 
114 114 
Id. § 311(c). If a PGR is instituted with respect to the patent, an IPR may not be filed until the PGR concludes.  § 311(c). If a PGR is instituted with respect to the patent, an IPR may not be filed until the PGR concludes. 
Id. 
115 115 
Id. § 315(b). A “real party in interest” refers to the “person entitled under the substantive law to enforce the right  § 315(b). A “real party in interest” refers to the “person entitled under the substantive law to enforce the right 
sued on.” sued on.” 
Real party in interest, BLACK’S LAW DICTIONARY (11th ed. 2019). A “privy” refers to “someone who controls , BLACK’S LAW DICTIONARY (11th ed. 2019). A “privy” refers to “someone who controls 
a lawsuit though not a party to it; someone whose interests are represented by a party to the lawsuit; and a successor in a lawsuit though not a party to it; someone whose interests are represented by a party to the lawsuit; and a successor in 
interest to anyone having a derivative claim.” interest to anyone having a derivative claim.” 
Privy, BLACK’S LAW DICTIONARY (11th ed. 2019). , BLACK’S LAW DICTIONARY (11th ed. 2019). 
116 35 U.S.C.
116 35 U.S.C.
 § 311(b). § 311(b). 
117 117 
Id. § 311(b).  § 311(b). 
118 118 
Cf. id. § 102(a)(1). § 102(a)(1). 
119 119 
Id. § 312.  § 312. 
120 120 
Id. § 314(a).  § 314(a). 
121 121 
See  id. §§ 313, 314; 37 C.F.R. § 42.107(a)–(b).   §§ 313, 314; 37 C.F.R. § 42.107(a)–(b).  
122 35 U.S.C. § 314(b). 122 35 U.S.C. § 314(b). 
123 37 C.F.R. § 42.108. 123 37 C.F.R. § 42.108. 
124 124 
See GAO PTAB REPORT,  GAO PTAB REPORT, 
supra notenote 102,  at 8; SOP 1, at 8; SOP 1, 
supra notenote 108, atat
 1.  1.  
125 35 U.S.C. § 314(a). 125 35 U.S.C. § 314(a). 
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determination by the Director whether to institute an inter partes review under this section shall 
determination by the Director whether to institute an inter partes review under this section shall 
be final and nonappealable.”126 be final and nonappealable.”126 
The AIA also prohibits institution of IPR in specific situations regarding related district court and 
The AIA also prohibits institution of IPR in specific situations regarding related district court and 
PTAB proceedings. First, the AIA provides that an IPR may not be instituted if, prior to the filing PTAB proceedings. First, the AIA provides that an IPR may not be instituted if, prior to the filing 
of the petition, the petitioner or “real party in interest” filed a district court action (i.e., a of the petition, the petitioner or “real party in interest” filed a district court action (i.e., a 
declaratory judgment action127) challenging any claim of the same patent.128 Thus, a party cannot declaratory judgment action127) challenging any claim of the same patent.128 Thus, a party cannot 
file a district court case requesting a declaratory judgment of invalidity and then file an IPR file a district court case requesting a declaratory judgment of invalidity and then file an IPR 
petition challenging any claims of the same patent.  petition challenging any claims of the same patent.  
Second, the AIA contains an estoppel provision that prohibits some so-called serial petitions, 
Second, the AIA contains an estoppel provision that prohibits some so-called serial petitions, 
which are discussed in greater depth below.129 The estoppel provision states that, once an IPR which are discussed in greater depth below.129 The estoppel provision states that, once an IPR 
results in a final written decision, the petitioner (or their real party in interest or privy) cannot results in a final written decision, the petitioner (or their real party in interest or privy) cannot 
“request or maintain” any other USPTO “proceeding” (including IPR) with respect to the same “request or maintain” any other USPTO “proceeding” (including IPR) with respect to the same 
patent claim based on “any ground that the petitioner raised or reasonably could have raised” in  based on “any ground that the petitioner raised or reasonably could have raised” in 
the original IPR.130 The estoppel provision does not, however, prevent the petitioner from filing a the original IPR.130 The estoppel provision does not, however, prevent the petitioner from filing a 
second IPR petition regarding the same patent claim(s) prior to a final written decision on the first second IPR petition regarding the same patent claim(s) prior to a final written decision on the first 
IPR. It also does not prevent a petitioner from filing a second IPR petition regarding different IPR. It also does not prevent a petitioner from filing a second IPR petition regarding different 
claims in the same patent. claims in the same patent. 
Through guidance and PTAB precedent, USPTO has developed guidelines for PTAB’s decisions 
Through guidance and PTAB precedent, USPTO has developed guidelines for PTAB’s decisions 
whether or not to institute IPRs in cases where none of the above-noted prohibitions on IPRs whether or not to institute IPRs in cases where none of the above-noted prohibitions on IPRs 
apply.131 These guidelines address common scenarios such as serial IPR petitions and parallel apply.131 These guidelines address common scenarios such as serial IPR petitions and parallel 
district court proceedings. The guidelines—and related reforms proposed by certain Members of district court proceedings. The guidelines—and related reforms proposed by certain Members of 
Congress and USPTO itself—are explained in more detail in the final section of this report. Congress and USPTO itself—are explained in more detail in the final section of this report. 
IPR Process Following Institution 
The framers of the AIA intended for IPR to serve as a faster, less costly alternative to district 
The framers of the AIA intended for IPR to serve as a faster, less costly alternative to district 
court litigation.132 The AIA itself sets forth certain requirements for conducting and deciding IPR court litigation.132 The AIA itself sets forth certain requirements for conducting and deciding IPR 
proceedings.133 As directed by the AIA,134 USPTO has supplemented those requirements by proceedings.133 As directed by the AIA,134 USPTO has supplemented those requirements by 
promulgating more detailed rules on PTAB trial practice and procedure.135 PTAB also provides promulgating more detailed rules on PTAB trial practice and procedure.135 PTAB also provides 
 
 
126 
126 
Id. § 314(d) (the “no-appeal provision”).  § 314(d) (the “no-appeal provision”). 
127 127 
Cf.  id. § 315(a)(3) (providing that this prohibition does not apply where the petitioner is sued for infringement and  § 315(a)(3) (providing that this prohibition does not apply where the petitioner is sued for infringement and 
responds with “[a] counterclaim challenging the validity of a claim”). responds with “[a] counterclaim challenging the validity of a claim”). 
128 128 
See  id. § 315(a)(1).  § 315(a)(1). 
129 129 
See infra  “Serial Petitions.”  130130
 35 U.S.C. § 315. 35 U.S.C. § 315. 
131 131 
See, e.g., Memorandum from USPTO Director Katherine K. Vidal to PTAB, , Memorandum from USPTO Director Katherine K. Vidal to PTAB, 
Interim Procedure for Discretionary 
Denials in AIA Post-Grant Proceedings with Parallel District Court Litigation (June 21, 2022),  (June 21, 2022), 
https://www.uspto.gov/sites/default/files/documents/interim_proc_discretionary_denials_aia_parallel_district_court_litihttps://www.uspto.gov/sites/default/files/documents/interim_proc_discretionary_denials_aia_parallel_district_court_liti
gation_memo_20220621_.pdf. gation_memo_20220621_.pdf. 
132 
132 
See H.R. REP. NO. 112-98, at 39–40 (2011) (stating that among the goals of the AIA were to “improv[e] patent H.R. REP. NO. 112-98, at 39–40 (2011) (stating that among the goals of the AIA were to “improv[e] patent 
quality and provid[e] a more efficient system for challenging patents that should not have issued” and to “limit quality and provid[e] a more efficient system for challenging patents that should not have issued” and to “limit 
unnecessary and counterproductive litigation costs”). unnecessary and counterproductive litigation costs”). 
133 35 U.S.C. §§ 316–319. 133 35 U.S.C. §§ 316–319. 
134 134 
Id. § 316(a) (“The Director shall prescribe regulations . . . .”).  § 316(a) (“The Director shall prescribe regulations . . . .”). 
135 135 
See 37 C.F.R. pt. 42.  37 C.F.R. pt. 42. 
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guidance on its standard practices for conducting these proceedings in its Consolidated Trial 
guidance on its standard practices for conducting these proceedings in its Consolidated Trial 
Practice Guide.136  Practice Guide.136  
Once an IPR is instituted, PTAB issues a scheduling order setting forth key dates and deadlines. 
Once an IPR is instituted, PTAB issues a scheduling order setting forth key dates and deadlines. 
The patent owner is given time to file a response to the petition—regardless of whether the The patent owner is given time to file a response to the petition—regardless of whether the 
patentee filed a preliminary response before institution—followed by sur-replies by each party to patentee filed a preliminary response before institution—followed by sur-replies by each party to 
address any new arguments.137  address any new arguments.137  
During the IPR, the patent owner may also file a motion either to cancel any challenged claims or 
During the IPR, the patent owner may also file a motion either to cancel any challenged claims or 
to amend claims by “propos[ing] a reasonable number of substitute claims” for each such to amend claims by “propos[ing] a reasonable number of substitute claims” for each such 
challenged claim that would not “enlarge the scope” of the existing claims.138 In March 2024, challenged claim that would not “enlarge the scope” of the existing claims.138 In March 2024, 
USPTO issued a notice of proposed rulemaking that would formalize a pilot program that it USPTO issued a notice of proposed rulemaking that would formalize a pilot program that it 
established in 2019 to give patent holders additional options when filing a motion to amend established in 2019 to give patent holders additional options when filing a motion to amend 
(MTA) their claims.139 Under this pilot program (and the proposed rule), patent holders may (MTA) their claims.139 Under this pilot program (and the proposed rule), patent holders may 
request “preliminary, non-binding guidance” from PTAB on the merits of an MTA.140 Patent request “preliminary, non-binding guidance” from PTAB on the merits of an MTA.140 Patent 
holders may also file either a revised MTA or a reply brief in support of the original MTA holders may also file either a revised MTA or a reply brief in support of the original MTA 
following the petitioner’s opposition and any preliminary guidance from PTAB.141 Patent holders following the petitioner’s opposition and any preliminary guidance from PTAB.141 Patent holders 
have had more success amending claims in AIA proceedings since the pilot program began in have had more success amending claims in AIA proceedings since the pilot program began in 
2019. USPTO notes that 24% of final determinations have granted at least one substitute claim 2019. USPTO notes that 24% of final determinations have granted at least one substitute claim 
during the pilot program, versus 14% previously.142 during the pilot program, versus 14% previously.142 
The petitioner in an IPR has the burden of proving unpatentability of challenged claims by a 
The petitioner in an IPR has the burden of proving unpatentability of challenged claims by a 
preponderance of the evidence.143 As in district court litigation, PTAB may need to resolve preponderance of the evidence.143 As in district court litigation, PTAB may need to resolve 
disagreements about claim construction (i.e., the interpretation of patent claims) in order to reach disagreements about claim construction (i.e., the interpretation of patent claims) in order to reach 
a decision as to their validity.144 PTAB currently applies the same claim construction standard a decision as to their validity.144 PTAB currently applies the same claim construction standard 
used in district court litigation,145 which requires PTAB to construe claim terms according to their used in district court litigation,145 which requires PTAB to construe claim terms according to their 
“ordinary and customary meaning . . . to a person of ordinary skill in the art in question at the “ordinary and customary meaning . . . to a person of ordinary skill in the art in question at the 
time of the invention.”146 To discern this meaning, PTAB must look to the claims themselves, the time of the invention.”146 To discern this meaning, PTAB must look to the claims themselves, the 
patent specification, documents from the prosecution of the patent (prosecution history), and, to a patent specification, documents from the prosecution of the patent (prosecution history), and, to a 
lesser degree, “extrinsic evidence” such as expert testimony, dictionaries, and treatises.147  lesser degree, “extrinsic evidence” such as expert testimony, dictionaries, and treatises.147  
 
 
136 PTAB, CONSOLIDATED TRIAL PRACTICE GUIDE (Nov. 2019), 
136 PTAB, CONSOLIDATED TRIAL PRACTICE GUIDE (Nov. 2019), 
https://www.uspto.gov/sites/default/files/documents/tpgnov.pdf [hereinafter CONSOLIDATED PTAB PRACTICE GUIDE]. https://www.uspto.gov/sites/default/files/documents/tpgnov.pdf [hereinafter CONSOLIDATED PTAB PRACTICE GUIDE]. 
137 37 C.F.R. § 42.107, 42.120; CONSOLIDATED PTAB PRACTICE GUIDE, 
137 37 C.F.R. § 42.107, 42.120; CONSOLIDATED PTAB PRACTICE GUIDE, 
supra  notenote 136, at 73–75. at 73–75. 
138 35 U.S.C. § 316(d). 138 35 U.S.C. § 316(d). 
139 Motion to Amend Practice and Procedures in Trial Proceedings Under the America Invents Act Before the Patent 139 Motion to Amend Practice and Procedures in Trial Proceedings Under the America Invents Act Before the Patent 
Trial and Appeal Board, 89 Fed. Reg. 15531 (Mar. 4, 2024). In addition to IPR, the pilot program and proposed rule Trial and Appeal Board, 89 Fed. Reg. 15531 (Mar. 4, 2024). In addition to IPR, the pilot program and proposed rule 
apply to PGR and derivation proceedings. apply to PGR and derivation proceedings. 
See id. . 
140 
140 
Id. at 15532.  at 15532. 
141 141 
See id. . 
142 142 
See id. at 15533.  at 15533. 
143 35 U.S.C. § 316(e). 143 35 U.S.C. § 316(e). 
144 144 
See supra  “How Do Courts Adjudicate Patent Rights?”.  145 145 
See Changes to the Claim Construction Standard for Interpreting Claims in Trial Proceedings Before the Patent Trial Changes to the Claim Construction Standard for Interpreting Claims in Trial Proceedings Before the Patent Trial 
and Appeal Board,and Appeal Board,
 83 Fed. Reg. 51340 (Oct. 11, 2018) (codified at 37 C.F.R. § 42.100(b)); Personalized Media 83 Fed. Reg. 51340 (Oct. 11, 2018) (codified at 37 C.F.R. § 42.100(b)); Personalized Media 
Commc’ns, LLC v. Apple Inc., 952 F.3d 1336, 1340 n.2 (Fed. Cir. 2020) (“Per recent regulation, Commc’ns, LLC v. Apple Inc., 952 F.3d 1336, 1340 n.2 (Fed. Cir. 2020) (“Per recent regulation, 
the Board[PTAB] applies the  applies the 
Phillips claim construction standard to IPR petitions filed on or after November 13, 2018.”).  claim construction standard to IPR petitions filed on or after November 13, 2018.”). 
146 Phillips v. AWH Corp., 415 F.3d 1303, 1313 (Fed. Cir. 2005). 
146 Phillips v. AWH Corp., 415 F.3d 1303, 1313 (Fed. Cir. 2005). 
147 147 
See id. at 1313–19.  at 1313–19. 
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As discussed below,148 some reform efforts seek to eliminate USPTO’s authority to depart from 
As discussed below,148 some reform efforts seek to eliminate USPTO’s authority to depart from 
the currently used claim construction standard, in light of the fact that PTAB previously employed the currently used claim construction standard, in light of the fact that PTAB previously employed 
a different standard. a different standard. 
Discovery in IPR 
Parties to an IPR may obtain evidence through discovery, although the scope of available 
Parties to an IPR may obtain evidence through discovery, although the scope of available 
discovery is narrower than in district court litigation. The AIA largely defers to USPTO to “set[] discovery is narrower than in district court litigation. The AIA largely defers to USPTO to “set[] 
forth standards and procedures for discovery,”149 specifying only that discovery shall be limited to forth standards and procedures for discovery,”149 specifying only that discovery shall be limited to 
“the deposition of witnesses submitting affidavits or declarations”150 and “what is otherwise “the deposition of witnesses submitting affidavits or declarations”150 and “what is otherwise 
necessary in the interest of justice.”151 USPTO has promulgated rules requiring each party, at a necessary in the interest of justice.”151 USPTO has promulgated rules requiring each party, at a 
minimum, to provide “routine discovery” comprising the disclosure of any exhibit cited by the minimum, to provide “routine discovery” comprising the disclosure of any exhibit cited by the 
party, disclosure of nonprivileged information inconsistent with the party’s litigation positions, party, disclosure of nonprivileged information inconsistent with the party’s litigation positions, 
and making witnesses who submit affidavits available for cross-examination.152  and making witnesses who submit affidavits available for cross-examination.152  
Under USPTO rules, the parties may also conduct discovery via “mandatory initial disclosures.” 
Under USPTO rules, the parties may also conduct discovery via “mandatory initial disclosures.” 
Despite their name, these “mandatory” disclosures are required only if the parties agree to them Despite their name, these “mandatory” disclosures are required only if the parties agree to them 
or, barring agreement, if PTAB grants a party’s motion to require them.153 The parties may agree or, barring agreement, if PTAB grants a party’s motion to require them.153 The parties may agree 
either on narrow initial disclosures modeled on those required in district court litigation154 or on a either on narrow initial disclosures modeled on those required in district court litigation154 or on a 
“more extensive” set of disclosures focusing on nonpublished prior art and secondary indicia of “more extensive” set of disclosures focusing on nonpublished prior art and secondary indicia of 
nonobviousness, as set forth in the Consolidated Trial Practice Guide.155 If the IPR is instituted, nonobviousness, as set forth in the Consolidated Trial Practice Guide.155 If the IPR is instituted, 
the parties may “automatically” take further discovery regarding information identified in the parties may “automatically” take further discovery regarding information identified in 
mandatory initial disclosures.156 mandatory initial disclosures.156 
Parties may agree or move to conduct additional discovery “in the interests of justice.”157 When 
Parties may agree or move to conduct additional discovery “in the interests of justice.”157 When 
determining whether additional discovery is in the interests of justice, PTAB looks to five factors, determining whether additional discovery is in the interests of justice, PTAB looks to five factors, 
known as the known as the 
Garmin factors: (1) whether there is more than a “mere possibility” or “mere factors: (1) whether there is more than a “mere possibility” or “mere 
allegation” that useful information will be found; (2) whether the discovery request is a pretext to allegation” that useful information will be found; (2) whether the discovery request is a pretext to 
seek the other party’s litigation positions or contentions; (3) whether the requesting party can seek the other party’s litigation positions or contentions; (3) whether the requesting party can 
obtain the information by other means; (4) whether the discovery request is “easily obtain the information by other means; (4) whether the discovery request is “easily 
understandable”; (5) and whether the request is overly burdensome.158 Finally, parties may move understandable”; (5) and whether the request is overly burdensome.158 Finally, parties may move 
to request authorization to compel testimony or documents from third parties, similar to issuing a to request authorization to compel testimony or documents from third parties, similar to issuing a 
subpoena in a civil lawsuit.159  subpoena in a civil lawsuit.159  
 
 
148 
148 
See infra  “Claim Construction: Should USPTO or Congress Decide the Right Standard?”. . 
149 35 U.S.C. § 316(a)(5). 149 35 U.S.C. § 316(a)(5). 
150 150 
Id. § 316(a)(5)(A).  § 316(a)(5)(A). 
151 151 
Id. § 316(a)(5)(B). § 316(a)(5)(B). 
152 37 C.F.R. § 42.51(b)(1).  152 37 C.F.R. § 42.51(b)(1).  
153 153 
Id. § 42.51(a)(1), (2).  § 42.51(a)(1), (2). 
154 CONSOLIDATED PTAB PRACTICE GUIDE, 154 CONSOLIDATED PTAB PRACTICE GUIDE, 
supra no no
te 136, at 29 (citing Fed. R. Civ. P. 26(a)(1)(A)). at 29 (citing Fed. R. Civ. P. 26(a)(1)(A)). 
155 155 
See id. at 30–31.  at 30–31. 
156 37 C.F.R. § 42.51(a)(1)(ii). 156 37 C.F.R. § 42.51(a)(1)(ii). 
157 157 
Id. § 42.51(a)(2)(i).  § 42.51(a)(2)(i). 
158 158 
See CONSOLIDATED PTAB PRACTICE GUIDE,  CONSOLIDATED PTAB PRACTICE GUIDE, 
supra  notenote 136, at 25–28 (citing Garmin Int’l, Inc. v. Cuozzo Speed at 25–28 (citing Garmin Int’l, Inc. v. Cuozzo Speed 
Techs. LLC, Case IPR2012-00001 (P.T.A.B. Mar. 5, 2013) (Paper 26) (precedential)).  Techs. LLC, Case IPR2012-00001 (P.T.A.B. Mar. 5, 2013) (Paper 26) (precedential)).  
159 37 C.F.R. § 42.52(a). 
159 37 C.F.R. § 42.52(a). 
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IPR Final Decisions, Director Review, and Appeals 
PTAB may decide an IPR based solely on written submissions by the parties, although the parties 
PTAB may decide an IPR based solely on written submissions by the parties, although the parties 
may request an oral hearing before the three-APJ panel.160 A typical hearing consists of about an may request an oral hearing before the three-APJ panel.160 A typical hearing consists of about an 
hour of oral argument from each side.161 Although usually the hearing solely involves attorney hour of oral argument from each side.161 Although usually the hearing solely involves attorney 
argument, live witness testimony may also be presented at the discretion of the panel.162 argument, live witness testimony may also be presented at the discretion of the panel.162 
PTAB must issue a final written decision within one year after it institutes the IPR, although this 
PTAB must issue a final written decision within one year after it institutes the IPR, although this 
deadline may be extended by up to six months for “good cause.”163 Final written decisions must deadline may be extended by up to six months for “good cause.”163 Final written decisions must 
address the patentability of each claim challenged by the petition, as well as any substitute claims address the patentability of each claim challenged by the petition, as well as any substitute claims 
sought to be added by the patentee.164 Final decisions are accompanied by publication of a sought to be added by the patentee.164 Final decisions are accompanied by publication of a 
certificate that cancels or confirms each claim depending on whether PTAB finds it to be certificate that cancels or confirms each claim depending on whether PTAB finds it to be 
patentable; the certificate may also incorporate into the patent any patentable new or amended patentable; the certificate may also incorporate into the patent any patentable new or amended 
claims.165 If the patent owner and any petitioner reach a settlement with one another prior to the claims.165 If the patent owner and any petitioner reach a settlement with one another prior to the 
final written decision, they may request to terminate the IPR as to that petitioner by filing a final written decision, they may request to terminate the IPR as to that petitioner by filing a 
motion to terminate and the settlement agreement.166 If no petitioners remain in the IPR, PTAB motion to terminate and the settlement agreement.166 If no petitioners remain in the IPR, PTAB 
may choose either to terminate the IPR or to proceed to a final written decision.167 may choose either to terminate the IPR or to proceed to a final written decision.167 
As originally enacted, the AIA allowed for parties to seek rehearing of a decision in an IPR only 
As originally enacted, the AIA allowed for parties to seek rehearing of a decision in an IPR only 
from PTAB itself.168 As discussed below, following a 2021 Supreme Court decision, parties may from PTAB itself.168 As discussed below, following a 2021 Supreme Court decision, parties may 
instead request review of final PTAB panel decisions by the USPTO Director.169 In addition, final instead request review of final PTAB panel decisions by the USPTO Director.169 In addition, final 
PTAB decisions (or denials of rehearing of a final decision) may be appealed to the Federal PTAB decisions (or denials of rehearing of a final decision) may be appealed to the Federal 
Circuit.170 Any of the parties to the IPR have a right to be a party to such an appeal.171 The Circuit.170 Any of the parties to the IPR have a right to be a party to such an appeal.171 The 
USPTO Director may also intervene in the appeal to defend PTAB’s decision, regardless of USPTO Director may also intervene in the appeal to defend PTAB’s decision, regardless of 
whether any party does so.172 PTAB’s decision to institute an IPR or not, however, is not whether any party does so.172 PTAB’s decision to institute an IPR or not, however, is not 
appealable.173 appealable.173 
 
 
160 
160 
Id. § 42.70(a); CONSOLIDATED PTAB PRACTICE GUIDE, § 42.70(a); CONSOLIDATED PTAB PRACTICE GUIDE, 
supra no no
te 136, at 81–82.at 81–82.
 
161 CONSOLIDATED PTAB PRACTICE GUIDE, 161 CONSOLIDATED PTAB PRACTICE GUIDE, 
supra no no
te 136,  at 81. at 81. 
162 162 
Id. at 85 (“ at 85 (“
The Board[PTAB] receives relatively few requests for presenting live testimony.”).  receives relatively few requests for presenting live testimony.”). 
163 35 U.S.C. § 316(a)(11). 163 35 U.S.C. § 316(a)(11). 
164 164 
Id. § 318(a).  § 318(a). 
165 165 
Id. § 318(b).  § 318(b). 
166 166 
Id. § 317.  § 317. 
167 167 
Id. § 317(a).  § 317(a). 
168 168 
Id. § 6(c); 37 C.F.R. § 42.71(d). § 6(c); 37 C.F.R. § 42.71(d). 
169 169 
See infra  “United States v. Arthrex”; ; 
“What Roles Do the USPTO Director and PTAB Management Play in PTAB 
Decisions?”.  
170 35 U.S.C. § 319. While the AIA affords a procedural right to appeal, the appealing party must have Article III 
170 35 U.S.C. § 319. While the AIA affords a procedural right to appeal, the appealing party must have Article III 
standing under the Constitution to maintain an appeal. standing under the Constitution to maintain an appeal. 
See generally Cong. Rsch. Serv., Cong. Rsch. Serv., 
ArtIII.S2.C1.6.1 Overview of 
Standing, https://constitution.congress.gov/browse/essay/artIII-S2-C1-6-1/ALDE_00012992/ (last visited Mar. 28, , https://constitution.congress.gov/browse/essay/artIII-S2-C1-6-1/ALDE_00012992/ (last visited Mar. 28, 
2024). A patent holder dissatisfied with a PTAB decision will usually have standing to appeal the cancellation of a 2024). A patent holder dissatisfied with a PTAB decision will usually have standing to appeal the cancellation of a 
patent claim. However, challengers to patents that do not practice the invention (e.g., nonprofit groups) may lack patent claim. However, challengers to patents that do not practice the invention (e.g., nonprofit groups) may lack 
standing to appeal PTAB decisions upholding the patent. standing to appeal PTAB decisions upholding the patent. 
See, e.g.,,
 Consumer Watchdog v. Wis. Alumni Rsch. Found., Consumer Watchdog v. Wis. Alumni Rsch. Found., 
753 F.3d 1258, 1262–63 (Fed. Cir. 2014) (holding that nonprofit consumer rights organization lacked standing to 753 F.3d 1258, 1262–63 (Fed. Cir. 2014) (holding that nonprofit consumer rights organization lacked standing to 
appeal IPR decision affirming patentability).appeal IPR decision affirming patentability).
 
171 35 U.S.C. § 319. 
171 35 U.S.C. § 319. 
172 Oil States Energy Servs., LLC v. Greene’s Energy Grp., LLC, 584 U.S. 325, 332–35 (2018). 172 Oil States Energy Servs., LLC v. Greene’s Energy Grp., LLC, 584 U.S. 325, 332–35 (2018). 
173 35 U.S.C. § 314(d). 173 35 U.S.C. § 314(d). 
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The Patent Trial and Appeal Board and Inter Partes Review 
 
IPR Statistics 
In a typical year, PTAB receives between 1,000 and 2,000 petitions for IPR or PGR.174 Of these 
In a typical year, PTAB receives between 1,000 and 2,000 petitions for IPR or PGR.174 Of these 
filings, the overwhelming majority are IPRs.175 In FY2023, for example, PTAB received 1,209 filings, the overwhelming majority are IPRs.175 In FY2023, for example, PTAB received 1,209 
IPR petitions (97.6%), compared with 30 PGR petitions (2.4%).176 IPR petitions (97.6%), compared with 30 PGR petitions (2.4%).176 
Litigating an IPR costs several hundreds of thousands of dollars in legal costs on average.177 
Litigating an IPR costs several hundreds of thousands of dollars in legal costs on average.177 
While expensive, an IPR is usually many times cheaper than litigating a patent suit in the federal While expensive, an IPR is usually many times cheaper than litigating a patent suit in the federal 
courts, which can cost several million dollars.178 courts, which can cost several million dollars.178 
IPR Outcomes 
Very roughly, PTAB denies institution—that is, declines to hear the IPR or PGR—in a little less 
Very roughly, PTAB denies institution—that is, declines to hear the IPR or PGR—in a little less 
than one-third of petitions.179 A similar number of cases settle.180 For example, of the 1,327 than one-third of petitions.179 A similar number of cases settle.180 For example, of the 1,327 
petitions resolved in FY2023, PTAB denied institution in 374 cases (28%), and 402 cases settled petitions resolved in FY2023, PTAB denied institution in 374 cases (28%), and 402 cases settled 
(30%).181 Thus, PTAB typically reaches a final written decision for between 35–40% of the (30%).181 Thus, PTAB typically reaches a final written decision for between 35–40% of the 
petitions it receives.182 petitions it receives.182 
In those IPRs and PGRs that do reach a final written decision, PTAB cancels some or all of the 
In those IPRs and PGRs that do reach a final written decision, PTAB cancels some or all of the 
patent claims at issue in the large majority of cases. In FY2023, for example, PTAB issued a final patent claims at issue in the large majority of cases. In FY2023, for example, PTAB issued a final 
written decision in 508 cases.183 Of those, it foundwritten decision in 508 cases.183 Of those, it found
 allall
 the claims unpatentable in 343 cases the claims unpatentable in 343 cases 
(67.5%), upheld all of the patent claims in 87 cases (17.1%), and reached a mixed result (i.e., (67.5%), upheld all of the patent claims in 87 cases (17.1%), and reached a mixed result (i.e., 
upholding some patent claims and canceling others) in 78 cases (15.4%).184upholding some patent claims and canceling others) in 78 cases (15.4%).184
 Figure 1 displays displays 
these outcome statistics as reported by USPTO. these outcome statistics as reported by USPTO. 
 
 
174 PTAB FY23 STATISTICS, 
174 PTAB FY23 STATISTICS, 
supra  notenote 112,  at 3 (1,239 post-issuance review petitions received in FY2023); USPTO, at 3 (1,239 post-issuance review petitions received in FY2023); USPTO, 
PTAB TRIAL STATISTICS:PTAB TRIAL STATISTICS:
 FY23 END OF YEAR OUTCOME ROUNDUP—IPR, PGR 3 (2022), FY23 END OF YEAR OUTCOME ROUNDUP—IPR, PGR 3 (2022), 
https://www.uspto.gov/sites/default/files/documents/ptab__aia_fy2022_roundup.pdf [hereinafter PTAB FY22 https://www.uspto.gov/sites/default/files/documents/ptab__aia_fy2022_roundup.pdf [hereinafter PTAB FY22 
Statistics]Statistics]
 (1,367 post-issuance review petitions received in FY2022); (1,367 post-issuance review petitions received in FY2022); 
see also Dani Kass,  Dani Kass, 
PTAB Filings Drop 
Alongside Declining Patent Litigation, LAW360 (Feb. 7, 2024, 11:02 PM), https://www.law360.com/articles/1794397 , LAW360 (Feb. 7, 2024, 11:02 PM), https://www.law360.com/articles/1794397 
(number of annual IPR filings between 2014 and 2023 ranging from a high of 1,723 petitions in 2017 to a low of 1,157 (number of annual IPR filings between 2014 and 2023 ranging from a high of 1,723 petitions in 2017 to a low of 1,157 
petitions in 2023). petitions in 2023). 
175 
175 
See Kass,  Kass, 
supra  notenote 174 (showing over 1,000 IPRs filed each year, but only several dozen PGRs). (showing over 1,000 IPRs filed each year, but only several dozen PGRs). 
176 PTAB FY23 STATISTICS, 176 PTAB FY23 STATISTICS, 
supra  notenote 112, at 3. at 3. 
177 AIPLA, REPORT OF THE ECONOMIC SURVEY 2019, at 52 (2019), https://ipwatchdog.com/wp-177 AIPLA, REPORT OF THE ECONOMIC SURVEY 2019, at 52 (2019), https://ipwatchdog.com/wp-
content/uploads/2021/08/AIPLA-Report-of-the-Economic-Survey-Relevant-Excerpts.pdf (median litigation costs for content/uploads/2021/08/AIPLA-Report-of-the-Economic-Survey-Relevant-Excerpts.pdf (median litigation costs for 
IPRs ranging from $100,000 to $350,000 depending on the type of case and amount in controversy). IPRs ranging from $100,000 to $350,000 depending on the type of case and amount in controversy). 
178 
178 
Id. at 50–52 (median total patent litigation costs ranging from $700,000 to $8 million depending on the type of case  at 50–52 (median total patent litigation costs ranging from $700,000 to $8 million depending on the type of case 
and amount in controversy); and amount in controversy); 
accord Stephen Yelderman,  Stephen Yelderman, 
Prior Art in Inter Partes Review, 104 IOWA L. REV. 2705, , 104 IOWA L. REV. 2705, 
2706 (2019)2706 (2019)
 (“[T]he cost of litigating an IPR to a final written decision was about $324,000, which pales in comparison (“[T]he cost of litigating an IPR to a final written decision was about $324,000, which pales in comparison 
to the $1–2 million reported cost of litigating a patent in court.”). to the $1–2 million reported cost of litigating a patent in court.”). 
179 
179 
See, e.g.,,
 PTAB FY23 STATISTICS, PTAB FY23 STATISTICS, 
supra  notenote 112, at 10 (institution denied for 28% of petitions in FY2023); PTAB at 10 (institution denied for 28% of petitions in FY2023); PTAB 
FY22 STATISTICS, FY22 STATISTICS, 
supra notenote 174, at 11 (institution denied for 30% of petitions in FY2022).at 11 (institution denied for 30% of petitions in FY2022).
 
180 
180 
See, e.g.,,
 PTAB FY23 STATISTICS, PTAB FY23 STATISTICS, 
supra  notenote 112, at 10 (30% of petitions settled in FY2023); PTAB FY22 at 10 (30% of petitions settled in FY2023); PTAB FY22 
STATISTICS, STATISTICS, 
supra notenote 174, at 11 (27% of petitions settled in FY2022).at 11 (27% of petitions settled in FY2022).
 
181 PTAB FY23 STATISTICS, 
181 PTAB FY23 STATISTICS, 
supra  notenote 112,  at 10. at 10. 
182 182 
See, e.g.,,
 id. (final written decision in 39% of petitions in FY2023); PTAB FY22 STATISTICS, (final written decision in 39% of petitions in FY2023); PTAB FY22 STATISTICS, 
supra notenote 174, at 11 at 11 
(final written decision in 37% of petitions in FY2022). (final written decision in 37% of petitions in FY2022). 
183 
183 
See PTAB FY23 STATISTICS,  PTAB FY23 STATISTICS, 
supra  notenote 112, at 10. at 10. 
184 184 
See  id. 
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Figure 1. IPR and PGR Outcomes by Petition in FY2023 
 
 
Source: USPTO, PTAB TRIAL STATISTICS: FY23 End of Year Outcome Roundup—IPR, PGR 10 (2023),  USPTO, PTAB TRIAL STATISTICS: FY23 End of Year Outcome Roundup—IPR, PGR 10 (2023), 
https://www.uspto.gov/sites/default/files/documents/ptab_aia_fy2023__roundup.pdfhttps://www.uspto.gov/sites/default/files/documents/ptab_aia_fy2023__roundup.pdf
.  Notes: “FWD” means final written decision by the Patent Trial and Appeal Board (PTAB). “IPR” refers to inter “FWD” means final written decision by the Patent Trial and Appeal Board (PTAB). “IPR” refers to inter 
partes review; “PGR” refers to post-grant review. partes review; “PGR” refers to post-grant review. 
Some critics of PTAB argue that because PTAB cancels at least one patent claim in over 80% of 
Some critics of PTAB argue that because PTAB cancels at least one patent claim in over 80% of 
its final written decisions, the panels may be biased against patent owners.185 While that number its final written decisions, the panels may be biased against patent owners.185 While that number 
is accurate, PTAB denies institution in nearly one-third of IPRs filed. Since a denial of institution is accurate, PTAB denies institution in nearly one-third of IPRs filed. Since a denial of institution 
leaves the patent claims intact, it arguably represents a “win” for the patent holder.186 Moreover, leaves the patent claims intact, it arguably represents a “win” for the patent holder.186 Moreover, 
because PTAB may institute an IPR only if it finds that “there is a reasonable likelihood that the because PTAB may institute an IPR only if it finds that “there is a reasonable likelihood that the 
petitioner would prevail with respect to at least 1 of the claims challenged,”187 it is perhaps not petitioner would prevail with respect to at least 1 of the claims challenged,”187 it is perhaps not 
surprising that most of the instituted IPRs in fact invalidate one or more claims.188 surprising that most of the instituted IPRs in fact invalidate one or more claims.188 
 
 
185 
185 
See Steve Brachmann & Gene Quinn, Steve Brachmann & Gene Quinn, 
Are More than 90 percent of Patents Challenged at the PTAB Defective?, , 
IPWATCHDOG (June 14, 2017, 10:00 AM), https://ipwatchdog.com/2017/06/14/90-percent-patents-challenged-ptab-IPWATCHDOG (June 14, 2017, 10:00 AM), https://ipwatchdog.com/2017/06/14/90-percent-patents-challenged-ptab-
defective/id=84343/ (arguing that the statistics suggest that either “PTAB APJs are being too aggressive in invalidating defective/id=84343/ (arguing that the statistics suggest that either “PTAB APJs are being too aggressive in invalidating 
patents or that the examiners are producing incredibly poor quality patents”). patents or that the examiners are producing incredibly poor quality patents”). 
186 
186 
See Angela Morris, Angela Morris, 
US PTAB Invalidation Rates Under the Microscope as Reform Bill Refiled, IAM (June 26, , IAM (June 26, 
2023), https://www.iam-media.com/article/us-ptab-invalidation-rates-under-the-microscope-reform-bill-refiled (“The 2023), https://www.iam-media.com/article/us-ptab-invalidation-rates-under-the-microscope-reform-bill-refiled (“The 
petitions that were denied institution should be viewed as a patent holder win.”). Counted in that way, one could argue petitions that were denied institution should be viewed as a patent holder win.”). Counted in that way, one could argue 
that the patent holder “wins” (374 denials and 87 written decisions upholding all claims) about as often as they “lose” that the patent holder “wins” (374 denials and 87 written decisions upholding all claims) about as often as they “lose” 
(343 written decisions finding all claims unpatentable and 78 finding some claims unpatentable). Some argue that (343 written decisions finding all claims unpatentable and 78 finding some claims unpatentable). Some argue that 
settlements should be also counted as losses for the patent holder, however. settlements should be also counted as losses for the patent holder, however. 
See Brachmann & Quinn, Brachmann & Quinn, 
supra  notenote 185 
(arguing that “many (if not all) of these [IPR] settlements result in outcomes unfavorable to the patent owner”). (arguing that “many (if not all) of these [IPR] settlements result in outcomes unfavorable to the patent owner”). 
Ultimately, how to characterize these various outcomes is a matter of interpretation. Ultimately, how to characterize these various outcomes is a matter of interpretation. 
187 35 U.S.C. § 314(a). 
187 35 U.S.C. § 314(a). 
188 188 
See Brachmann & Quinn, Brachmann & Quinn, 
supra  notenote 185 (“If [PTAB] judges are doing a really good job on institution, one should (“If [PTAB] judges are doing a really good job on institution, one should 
expect to see that most of the decisions instituted reach a fairly favorable petitioner outcome.” (quoting Brian expect to see that most of the decisions instituted reach a fairly favorable petitioner outcome.” (quoting Brian 
Howard)). Howard)). 
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When appealed to the Federal Circuit, the large majority of PTAB findings on patent validity or 
When appealed to the Federal Circuit, the large majority of PTAB findings on patent validity or 
invalidity are affirmed.189 One study found an affirmance rate for IPRs of over 90%.190 While invalidity are affirmed.189 One study found an affirmance rate for IPRs of over 90%.190 While 
district court patent validity findings are also usually affirmed by the Federal Circuit, the district court patent validity findings are also usually affirmed by the Federal Circuit, the 
affirmance rate (85%) is somewhat lower.191 Notably, the Federal Circuit reverses district courts affirmance rate (85%) is somewhat lower.191 Notably, the Federal Circuit reverses district courts 
on patent validity issues at a higher rate (12.1% reversal rate) than it does PTAB decisions (4.8% on patent validity issues at a higher rate (12.1% reversal rate) than it does PTAB decisions (4.8% 
reversal rate).192 reversal rate).192 
 
 
189 Matthew G. Sipe, 
189 Matthew G. Sipe, 
Experts, Generalists, Laypeople—and the Federal Circuit, 32 HARV. J.L. & TECH. 575, 578 , 32 HARV. J.L. & TECH. 575, 578 
(2019). (2019). 
190 
190 
Id. at 604 tbl.7.  at 604 tbl.7. 
191 191 
Id. at 610 tbl.15.  at 610 tbl.15. 
192 192 
See id. (“Three tendencies emerge from this picture: (1) the PTAB is affirmed notably more often than district courts (“Three tendencies emerge from this picture: (1) the PTAB is affirmed notably more often than district courts 
on validity issues; (2) district court decisions tend to be reversed outright, rather than vacated or remanded; and (3) on validity issues; (2) district court decisions tend to be reversed outright, rather than vacated or remanded; and (3) 
PTAB decisions, on the other hand, experience both types of non-affirmance in roughly equal measure.”). PTAB decisions, on the other hand, experience both types of non-affirmance in roughly equal measure.”). 
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“Big Tech” and IPRs 
Some observers allege that large technology companies lobbied for the creation of PTAB and are its primary 
Some observers allege that large technology companies lobbied for the creation of PTAB and are its primary 
beneficiaries.193 As evidence, critics note that some so-called “big tech” firms are among the most frequent users beneficiaries.193 As evidence, critics note that some so-called “big tech” firms are among the most frequent users 
of IPRs. According to one analysis, in 2021, Samsung, Apple, Google, Intel, and Microsoft of IPRs. According to one analysis, in 2021, Samsung, Apple, Google, Intel, and Microsoft 
col ectivelycollectively accounted for  accounted for 
81% of PTAB petitions filed by the top 10 petitioners during that year.194 Critics allege that such companies are 81% of PTAB petitions filed by the top 10 petitioners during that year.194 Critics allege that such companies are 
using PTAB as “a key tool in their predatory infringement strategies.”195 using PTAB as “a key tool in their predatory infringement strategies.”195 
Large technology firms are also among the most frequent defendants in patent litigation.196 Some stakeholders Large technology firms are also among the most frequent defendants in patent litigation.196 Some stakeholders 
claim that financial incentives may lead these companies to infringe patents more often than smaller firms.197 This claim that financial incentives may lead these companies to infringe patents more often than smaller firms.197 This 
view holds that well-resourced firms may choose to engage in a practice called view holds that well-resourced firms may choose to engage in a practice called 
efficient infringement, in which a firm , in which a firm 
intentionally infringes a patent rather than purchasing or licensing it, based on the calculation that potential profits intentionally infringes a patent rather than purchasing or licensing it, based on the calculation that potential profits 
outweigh the potential costs associated with legal fees or damages it may owe as a result of infringement.198 outweigh the potential costs associated with legal fees or damages it may owe as a result of infringement.198 
Some observers argue that the practice of efficient infringement has been encouraged by recent legal changes, Some observers argue that the practice of efficient infringement has been encouraged by recent legal changes, 
which have made obtaining injunctive relief for patent infringement (i.e., a court order stopping the defendant’s which have made obtaining injunctive relief for patent infringement (i.e., a court order stopping the defendant’s 
infringing activities) more difficult to obtain.199 They claim that when injunctive relief is not granted and adequate infringing activities) more difficult to obtain.199 They claim that when injunctive relief is not granted and adequate 
damages are not awarded to patent owners whose rights have been infringed, potential infringers may decide that damages are not awarded to patent owners whose rights have been infringed, potential infringers may decide that 
the economic benefits of infringement outweigh the potential costs of being sued for patent infringement.200 the economic benefits of infringement outweigh the potential costs of being sued for patent infringement.200 
Others argue that large technology firms are frequently sued not because they are more likely to infringe patents Others argue that large technology firms are frequently sued not because they are more likely to infringe patents 
but because they are attractive targets of abusive litigation practices. Such practices, they claim, often involve so-but because they are attractive targets of abusive litigation practices. Such practices, they claim, often involve so-
called “patent called “patent 
trol strolls”201 asserting low quality patents that should not have been granted by USPTO.202 For ”201 asserting low quality patents that should not have been granted by USPTO.202 For 
example, in 2022, Google’s general counsel argued the declining quality of U.S. patents was causing an uptick in example, in 2022, Google’s general counsel argued the declining quality of U.S. patents was causing an uptick in 
abusive patent litigation and accused patent abusive patent litigation and accused patent 
trol strolls and opportunistic companies of weaponizing such patents against  and opportunistic companies of weaponizing such patents against 
their rivals.203 their rivals.203 
 
 
193 
193 
See Adam Mossoff, Adam Mossoff, 
Big Tech’s Abuse of Patent Owners in the PTAB Must End, HERITAGE FOUNDATION 5–6 (June , HERITAGE FOUNDATION 5–6 (June 
29, 2023), https://www.heritage.org/sites/default/files/2023-06/LM336.pdf; Paul R. Michel, 29, 2023), https://www.heritage.org/sites/default/files/2023-06/LM336.pdf; Paul R. Michel, 
Big Tech Has a Patent 
Violation Problem, HARVARD BUSINESS REVIEW (Aug. 5, 2023), https://hbr.org/2022/08/big-tech-has-a-patent-, HARVARD BUSINESS REVIEW (Aug. 5, 2023), https://hbr.org/2022/08/big-tech-has-a-patent-
violation-problem. violation-problem. 
194 Paul Michel & Chris Israel, 
194 Paul Michel & Chris Israel, 
Don’t Let Big Tech Sabotage U.S. Innovators’ Protections, BLOOMBERG LAW (Apr. 22, , BLOOMBERG LAW (Apr. 22, 
2022) (companies listed in the order they appear in the article). 2022) (companies listed in the order they appear in the article). 
195 Mossoff, 
195 Mossoff, 
supra note note
 193, at 5–6;  at 5–6; 
see Michel,  Michel, 
supra note note
 193.  196 196 
See Figure 11 in UNIFIED PATENTS,  Figure 11 in UNIFIED PATENTS, 
2022 Patent Dispute Report (Jan. 5, 2023),  (Jan. 5, 2023), 
https://www.unifiedpatents.com/insights/2023/1/4/2022-patent-dispute-report (identifying Alphabet, Amazon, Apple, https://www.unifiedpatents.com/insights/2023/1/4/2022-patent-dispute-report (identifying Alphabet, Amazon, Apple, 
AT&T, Cisco, Lenovo, Microsoft, Samsung, Verizon, and Walmart as the most frequently named defendants in patent AT&T, Cisco, Lenovo, Microsoft, Samsung, Verizon, and Walmart as the most frequently named defendants in patent 
infringement suits in U.S. federal courts in 2022).  infringement suits in U.S. federal courts in 2022).  
197 
197 
See Michel, Michel, 
supra  notenote 193. 
198 198 
See Julie Turner, Julie Turner, 
The Nonmanufacturing Patent Owner: Toward a Theory of Efficient Infringement, 86 CAL. L. REV. , 86 CAL. L. REV. 
179, 210 (1998). 179, 210 (1998). 
199 
199 
See Kristen Osenga, “Kristen Osenga, “
Efficient” Infringement and Other Lies, 52 SETON HALL L. REV. 1085 (2022); Adam Mossoff, , 52 SETON HALL L. REV. 1085 (2022); Adam Mossoff, 
Institutional Design in Patent Law: Private Property Rights or Regulatory Entitlements, 92 S. CAL. L. REV. 921 (2019). , 92 S. CAL. L. REV. 921 (2019). 
In the 2006 case In the 2006 case 
eBay v. MercExchange, the Supreme Court held that an equitable balancing test governed the decision , the Supreme Court held that an equitable balancing test governed the decision 
of whether a district court should issue a permanent injunction in patent infringement cases, reversing the Federal of whether a district court should issue a permanent injunction in patent infringement cases, reversing the Federal 
Circuit rule that injunctions should issue “absent exceptional circumstances.” 547 U.S. 388 (2006).Circuit rule that injunctions should issue “absent exceptional circumstances.” 547 U.S. 388 (2006).
 
200 200 
See Mossoff, Mossoff, 
supra  notenote 199,  at 939. According to one commentator, when injunctive relief is not routinely granted, at 939. According to one commentator, when injunctive relief is not routinely granted, 
“it makes much more sense for a potential infringer to infringe now—and pay later. At worst, if an injunction is not “it makes much more sense for a potential infringer to infringe now—and pay later. At worst, if an injunction is not 
granted following a patent infringement trial, the infringer will simply have to pay damages for past infringement and granted following a patent infringement trial, the infringer will simply have to pay damages for past infringement and 
an ongoing royalty for continued, future infringement. This result is akin to having taken a license to start with, but an ongoing royalty for continued, future infringement. This result is akin to having taken a license to start with, but 
with the bonus of an interest-free loan for the period of infringement prior to and during the trial period.” Osenga, with the bonus of an interest-free loan for the period of infringement prior to and during the trial period.” Osenga, 
supra  notenote 199, at 1087. at 1087. 
201 “Patent troll” is a pejorative term for patent plaintiffs that enforce patents but do not manufacture or sell products. 
201 “Patent troll” is a pejorative term for patent plaintiffs that enforce patents but do not manufacture or sell products. 
FTC, FTC, 
supra  notenote 9, at 15–17. According to an opinion from the Supreme Court, “Trolls, in the patois of the patent  at 15–17. According to an opinion from the Supreme Court, “Trolls, in the patois of the patent 
community, are entities that hold patents for the primary purpose of enforcing them against alleged infringers, often community, are entities that hold patents for the primary purpose of enforcing them against alleged infringers, often 
exacting outsized licensing fees on threat of litigation.” Halo Elecs., Inc. v. Pulse Elecs., Inc. 579 U.S. 93, 109 (2016). exacting outsized licensing fees on threat of litigation.” Halo Elecs., Inc. v. Pulse Elecs., Inc. 579 U.S. 93, 109 (2016). 
202 Patent quality generally refers to whether granted patents actually meet the statutory standards of patentability. 
202 Patent quality generally refers to whether granted patents actually meet the statutory standards of patentability. 
These include requirements that the invention claimed in a patent be novel, nonobvious, and clearly described. These include requirements that the invention claimed in a patent be novel, nonobvious, and clearly described. 
(continued...) 
(continued...) 
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Post-Grant Review 
In addition to IPR, the AIA created PGR, another administrative proceeding that can result in In addition to IPR, the AIA created PGR, another administrative proceeding that can result in 
cancellation of an issued patent.204 There are cancellation of an issued patent.204 There are 
twothree primary differences between PGR and IPR. primary differences between PGR and IPR.
205 The first difference is the time window for filing a PGR. A PGR must be filed  First, a petition for PGR may be filed only during the first nine during the first nine 
months after a patent issues.months after a patent issues.
206 An IPR205 An IPR petition, by contrast, may be filed only , by contrast, may be filed only 
after the window for filing  the window for filing 
PGR ends; that is, an IPR must be filed more than nine months after the patent issues (and after PGR ends; that is, an IPR must be filed more than nine months after the patent issues (and after 
any PGR regarding the any PGR regarding the 
patent concludes).206 Second, the standard for instituting a PGR is higher, requiring PTAB to find “that it is more likely than not that at least 1 of the claims challenged in the petition is unpatentable.”207 By contrast, institution of IPR requires only “a reasonable likelihood that the petitioner would prevail with respect to at least 1 of the claims challenged in the petition.”208 
The third main difference between PGR and IPR concerns the grounds for cancellation that may be presented to PTAB. Whilepatent concludes).207 
The second main difference is the grounds for cancellation that may be presented in a PGR. The grounds for challenging a patent in IPR are more limited: an IPR may challenge a patent claim  an IPR may challenge a patent claim 
only on only on 
the basisgrounds of anticipation (35 U.S.C. § 102) or obviousness (35 U.S.C. § 103) of anticipation (35 U.S.C. § 102) or obviousness (35 U.S.C. § 103)
, and may rely only based on prior art patents or printed publications (and not other forms of prior art, such as  on prior art patents or printed publications (and not other forms of prior art, such as 
public uses)public uses)
.208 By contrast,,209 a PGR  a PGR 
petition may challenge whether a patent claim meets may challenge whether a patent claim meets 
any of  of 
the requirements for validity in the Patent Act.the requirements for validity in the Patent Act.
209 210 For example, For example, 
the petitiona PGR petitioner may argue that the  may argue that the 
patent is not directed to patentable subject matter under 35 U.S.C. § 101 or that the claims are patent is not directed to patentable subject matter under 35 U.S.C. § 101 or that the claims are 
indefinite under 35 U.S.C. § indefinite under 35 U.S.C. § 
112210112—arguments that are not available in IPR. —arguments that are not available in IPR. 
Procedurally, PGR functions similarly to IPR. Anyone other than the patent holder may file a 
Procedurally, PGR functions similarly to IPR. Anyone other than the patent holder may file a 
petition with USPTO requesting that PTAB initiate PGR to review the validity of the patent.211 petition with USPTO requesting that PTAB initiate PGR to review the validity of the patent.211 
After a PGR petition is filed, the patent owner may file a preliminary response arguing that the After a PGR petition is filed, the patent owner may file a preliminary response arguing that the 
patent claims meet all patenting requirements.212 Based on the petition and any response, the patent claims meet all patenting requirements.212 Based on the petition and any response, the 
USPTO Director determines whether “it is more likely than not that at least 1 of the claims USPTO Director determines whether “it is more likely than not that at least 1 of the claims 
challenged in the petition is unpatentable.”213 If so, PTAB may institute review.214 PTAB may also challenged in the petition is unpatentable.”213 If so, PTAB may institute review.214 PTAB may also 
institute review if the petition “raises a novel or unsettled legal question that is important to other institute review if the petition “raises a novel or unsettled legal question that is important to other 
patents or patent applications.”215 As patents or patent applications.”215 As 
noted above with respect towith IPRs, the decision whether to  IPRs, the decision whether to 
institute a PGR is unreviewable.  institute a PGR is unreviewable.  
 
 
203 Halimah DeLaine Prado, 
203 Halimah DeLaine Prado, 
Reforming the Patent System to Support American Innovation, GOOGLE: THE KEYWORD, , GOOGLE: THE KEYWORD, 
(Apr. 28, 2022), https://blog.google/outreach-initiatives/public-policy/reforming-the-patent-system-to-support-(Apr. 28, 2022), https://blog.google/outreach-initiatives/public-policy/reforming-the-patent-system-to-support-
american-innovation/. american-innovation/. 
204 35 U.S.C. §§ 321–329. 
204 35 U.S.C. §§ 321–329. 
205 205 
Another difference is that the standard for instituting IPR is lower, requiring only “a reasonable likelihood that the petitioner would prevail with respect to at least 1 of the claims challenged in the petition.” Id. § 314(a). PTAB may institute a PGR only when it finds “that it is more likely than not that at least 1 of the claims challenged in the petition is unpatentable.” Id. § 324(a).  
206 Id. § 321(c). 207 Id. § 311(c).  208 Id. § 311(b). 209 Id. § 282(b). 210 Id. 
Id. § 321(c).  206 Id. § 311(c).  207 Id. § 324(a). 208 Id. § 314(a). 209 Id. § 311(b). 210 Id. § 321(b). 211 211 
Id. § 321(a).  § 321(a). 
212 212 
Id. § 323.  § 323. 
213 213 
Id. § 324(a). The USPTO Director has delegated this authority to PTAB. 37 C.F.R. § 42.4 (“ § 324(a). The USPTO Director has delegated this authority to PTAB. 37 C.F.R. § 42.4 (“
The Board[PTAB] institutes the  institutes the 
trial on behalf of the Director.”); Thryv, Inc. v. Click-to-Call Techs., LP, 590 U.S. 45, 49 (2020) (“The Director has trial on behalf of the Director.”); Thryv, Inc. v. Click-to-Call Techs., LP, 590 U.S. 45, 49 (2020) (“The Director has 
delegated institution authority to the Patent Trial and Appeal Board.”). delegated institution authority to the Patent Trial and Appeal Board.”). 
214 35 U.S.C. § 324(a). Notably, the decision whether to institute is permissive, rather than mandatory. 
214 35 U.S.C. § 324(a). Notably, the decision whether to institute is permissive, rather than mandatory. 
IdSee id. (stating that  (stating that 
“the director may not authorize” PGR ““the director may not authorize” PGR “
unless” the petitioner demonstrates that it is more likely than not that at least ” the petitioner demonstrates that it is more likely than not that at least 
one claim is unpatentable, but not mandating institution (emphasis added)). one claim is unpatentable, but not mandating institution (emphasis added)). 
215 
215 
Id. § 324( § 324(
cb). ). 
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If PTAB institutes review, the patent owner may file a full response to the petition; the petitioner 
If PTAB institutes review, the patent owner may file a full response to the petition; the petitioner 
may file a reply; and, generally, the patent owner may file a sur-reply.216 The patent owner may may file a reply; and, generally, the patent owner may file a sur-reply.216 The patent owner may 
also file a motion to amend the claims.217 Following the sur-reply, PTAB holds a hearing where also file a motion to amend the claims.217 Following the sur-reply, PTAB holds a hearing where 
the petitioner and patent owner present arguments regarding whether the patent meets the relevant the petitioner and patent owner present arguments regarding whether the patent meets the relevant 
requirements for patenting.218 Following the hearing, PTAB issues a final written decision requirements for patenting.218 Following the hearing, PTAB issues a final written decision 
determining whether the patent claims are valid.219 A party dissatisfied with the final written determining whether the patent claims are valid.219 A party dissatisfied with the final written 
decision may seek review by the USPTO Director220 or appeal to the Federal Circuit.221 If, after decision may seek review by the USPTO Director220 or appeal to the Federal Circuit.221 If, after 
all appeals, the patent claims are held invalid, USPTO issues a certificate cancelling those all appeals, the patent claims are held invalid, USPTO issues a certificate cancelling those 
claims.222 claims.222 
Covered Business Method Review 
The AIA also introduced CBM review, a time-limited administrative proceeding for reviewing The AIA also introduced CBM review, a time-limited administrative proceeding for reviewing 
patents relating to methods of doing business.223 CBM review followed many of the same patents relating to methods of doing business.223 CBM review followed many of the same 
procedures as PGR,224 with several differences. A CBM review petition could be filed only by a procedures as PGR,224 with several differences. A CBM review petition could be filed only by a 
party who “has been sued for infringement of the patent or has been charged with infringement party who “has been sued for infringement of the patent or has been charged with infringement 
under that patent” and only against a patent that is the subject of the suit.225 Moreover, the patent under that patent” and only against a patent that is the subject of the suit.225 Moreover, the patent 
had to claim a “covered business method,” which the statute defined as “a method or had to claim a “covered business method,” which the statute defined as “a method or 
corresponding apparatus for performing data processing or other operations used in the practice, corresponding apparatus for performing data processing or other operations used in the practice, 
administration, or management of a financial product or service, except that the term [did] not administration, or management of a financial product or service, except that the term [did] not 
include patents for technological inventions.”226 The CBM review program sunsetted on include patents for technological inventions.”226 The CBM review program sunsetted on 
September 16, 2020.227 September 16, 2020.227 
Comparison of PTAB and Other Post-Grant Proceedings 
Table 1 compares filing deadlines, standing, grounds for invalidation, and evidentiary thresholds compares filing deadlines, standing, grounds for invalidation, and evidentiary thresholds 
for the three types of post-grant proceedings established by the AIA—PGR, IPR, and CBM for the three types of post-grant proceedings established by the AIA—PGR, IPR, and CBM 
review—as well as ex parte reexaminations, which predate the AIA and are not administered by review—as well as ex parte reexaminations, which predate the AIA and are not administered by 
PTAB. PTAB. 
 
 
216 
216 
See CONSOLIDATED PTAB PRACTICE GUIDE, CONSOLIDATED PTAB PRACTICE GUIDE,
 supra  notenote 136;  see also 35 U.S.C. § 326(a) (giving USPTO Director  35 U.S.C. § 326(a) (giving USPTO Director 
the power to promulgate regulations governing PGR). the power to promulgate regulations governing PGR). 
217 35 U.S.C. § 326(a)(9). 
217 35 U.S.C. § 326(a)(9). 
218 218 
See id. § 326(a)(10).  § 326(a)(10). 
219 219 
Id. § 328(a).  § 328(a). 
220 220 
See infra  “Interim Director Review Process.”  221 35 U.S.C. § 329. 221 35 U.S.C. § 329. 
222 222 
Id. § 328(b).  § 328(b). 
223 Leahy-Smith America Invents Act, Pub. L. No. 112-29, 125 Stat. 331, § 18(a) (2011). 223 Leahy-Smith America Invents Act, Pub. L. No. 112-29, 125 Stat. 331, § 18(a) (2011). 
224 224 
Id. § 18(a)(1)(A).  § 18(a)(1)(A). 
225 225 
Id. § 18(a)(1)(B).  § 18(a)(1)(B). 
226 226 
Id. § 18(d)(1).  § 18(d)(1). 
227 227 
Id. § 18(a)(3).   § 18(a)(3).  
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Table 1. USPTO Post-Grant Proceedings 
Time for 
Challenger 
Evidentiary 
Sunset 
Proceeding 
Filing 
(Standing) 
Grounds 
Threshold 
Date 
Ex Parte 
Any time. 
Any time. 
Anyone, 
Anyone, 
Novelty or 
Novelty or 
Substantial new 
Substantial new 
None. 
None. 
Reexamination 
including the 
including the 
nonobviousness on 
nonobviousness on 
question of 
question of 
(not PTAB-
USPTO 
USPTO 
the basis of patents or  patentability. 
the basis of patents or  patentability. 
administered) 
Director on 
Director on 
printed publications. 
printed publications. 
his/her own 
his/her own 
initiative. initiative. 
PGR 
No later than 
No later than 
Anyone except  Patent-eligible subject 
Anyone except  Patent-eligible subject 
More likely than 
More likely than 
None. 
None. 
nine months 
nine months 
the patent 
the patent 
matter; novelty; 
matter; novelty; 
not that at least 
not that at least 
after issuance 
after issuance 
owner. 
owner. 
nonobviousness; 
nonobviousness; 
one of the 
one of the 
or reissuance 
or reissuance 
indefiniteness; written 
indefiniteness; written 
challenged patent 
challenged patent 
of a patent. 
of a patent. 
description; 
description; 
claims is 
claims is 
enablement. 
enablement. 
unpatentable. 
unpatentable. 
IPR 
No earlier than  Anyone except  Novelty or 
No earlier than  Anyone except  Novelty or 
Reasonable 
Reasonable 
None. 
None. 
(1) nine 
(1) nine 
the patent 
the patent 
nonobviousness on 
nonobviousness on 
likelihood that the 
likelihood that the 
months after 
months after 
owner. 
owner. 
the basis of patents or  petitioner would 
the basis of patents or  petitioner would 
patent grant or 
patent grant or 
printed publications. 
printed publications. 
prevail with 
prevail with 
(2) after the 
(2) after the 
respect to at least 
respect to at least 
termination of 
termination of 
one of the 
one of the 
any PGR. 
any PGR. 
challenged claims. 
challenged claims. 
CBM Review 
Any time 
Any time 
A person or 
A person or 
May challenge only a 
May challenge only a 
More likely than 
More likely than 
Sept. 
Sept. 
before the 
before the 
the person’s 
the person’s 
covered business 
covered business 
not that at least 
not that at least 
16, 
16, 
sunset date. 
sunset date. 
real party in 
real party in 
method patent. 
method patent. 
one of the 
one of the 
2020. 
2020. 
interest or 
interest or 
May raise patent-
May raise patent-
challenged claims 
challenged claims 
privy who has 
privy who has 
eligible subject 
eligible subject 
is unpatentable. 
is unpatentable. 
been sued or 
been sued or 
matter; novelty; 
matter; novelty; 
charged with 
charged with 
nonobviousness; 
nonobviousness; 
infringement 
infringement 
indefiniteness; written 
indefiniteness; written 
under the 
under the 
description; or 
description; or 
challenged 
challenged 
enablement issues. 
enablement issues. 
patent. 
patent. 
Source: Created byCreated by
 CRS based on Title 35 chapters 30 (ex parte reexamination), 31 (IPR), and 32 (PGR), and CRS based on Title 35 chapters 30 (ex parte reexamination), 31 (IPR), and 32 (PGR), and 
Public Law No. 112-29, 125 Stat. 331, section 18 (CBM review). Public Law No. 112-29, 125 Stat. 331, section 18 (CBM review). 
Notes: “PTAB” means the Patent Trial and Appeal Board; “PGR” means post-grant review; “IPR” means inter : “PTAB” means the Patent Trial and Appeal Board; “PGR” means post-grant review; “IPR” means inter 
partes review; “CBM” means covered business method. partes review; “CBM” means covered business method. 
PTAB at the Supreme Court 
Starting in 2016, the Supreme Court decided six major cases involving PTAB in a five-year Starting in 2016, the Supreme Court decided six major cases involving PTAB in a five-year 
period.228 The Court’s interest in PTAB may reflect, to some degree, novel statutory and period.228 The Court’s interest in PTAB may reflect, to some degree, novel statutory and 
constitutional issues raised by the AIA, as well as PTAB’s importance in the patent system. This constitutional issues raised by the AIA, as well as PTAB’s importance in the patent system. This 
section surveys the facts and holdings of each of these cases. section surveys the facts and holdings of each of these cases. 
 
 
228 
228 
See Cuozzo Speed Techs., LLC v. Lee, 579 U.S. 261 (2016); SAS Inst., Inc. v. Iancu, 138 S. Ct. 1348 (2018); Oil Cuozzo Speed Techs., LLC v. Lee, 579 U.S. 261 (2016); SAS Inst., Inc. v. Iancu, 138 S. Ct. 1348 (2018); Oil 
States Energy Servs., LLC v. Greene's Energy Grp., LLC, 584 U.S. 325 (2018); Return Mail, Inc. v. U.S. Postal Serv., States Energy Servs., LLC v. Greene's Energy Grp., LLC, 584 U.S. 325 (2018); Return Mail, Inc. v. U.S. Postal Serv., 
139 S. Ct. 1853 (2019); Thryv, Inc. v. Click-to-Call Techs., LP, 590 U.S. 45 (2020); United States v. Arthrex, Inc., 594 139 S. Ct. 1853 (2019); Thryv, Inc. v. Click-to-Call Techs., LP, 590 U.S. 45 (2020); United States v. Arthrex, Inc., 594 
U.S. 1 (2021).U.S. 1 (2021).
 
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Statutory Interpretation Cases  
Four of the six Supreme Court cases addressing PTAB have raised questions regarding the correct Four of the six Supreme Court cases addressing PTAB have raised questions regarding the correct 
interpretation of provisions of the AIA, including whether the AIA gives PTAB authority to select interpretation of provisions of the AIA, including whether the AIA gives PTAB authority to select 
a certain legal standard for claim construction in AIA proceedings (yes), whether the AIA allows a certain legal standard for claim construction in AIA proceedings (yes), whether the AIA allows 
PTAB to institute an IPR for only some of the patent claims challenged in a petition (no), and PTAB to institute an IPR for only some of the patent claims challenged in a petition (no), and 
whether the federal government is a “person” that may file a petition for IPR (no). whether the federal government is a “person” that may file a petition for IPR (no). 
In addition, two of these cases addressed the proper interpretation of 35 U.S.C. § 314(d), an AIA 
In addition, two of these cases addressed the proper interpretation of 35 U.S.C. § 314(d), an AIA 
provision stating that the decision whether or not to institute an IPR is “final and provision stating that the decision whether or not to institute an IPR is “final and 
nonappealable.”229 As discussed below, the Supreme Court held that PTAB’s decision to institute nonappealable.”229 As discussed below, the Supreme Court held that PTAB’s decision to institute 
an IPR cannot be appealed on grounds that the petition did not comply with the AIA’s an IPR cannot be appealed on grounds that the petition did not comply with the AIA’s 
requirements or was untimely. requirements or was untimely. 
Cuozzo Speed Technologies, LLC v. Lee 
The first Supreme Court decision to address IPR, 2016’s 
The first Supreme Court decision to address IPR, 2016’s 
Cuozzo Speed Technologies, LLC v. Lee, , 
involved two separate issues: (1) the scope of Section 314(d)’s no-appeal provision and (2) involved two separate issues: (1) the scope of Section 314(d)’s no-appeal provision and (2) 
whether the AIA authorized USPTO to issue a regulation adopting a “broadest reasonable whether the AIA authorized USPTO to issue a regulation adopting a “broadest reasonable 
construction” (BRC) standard for claim construction in IPR proceedings.230 The Court concluded construction” (BRC) standard for claim construction in IPR proceedings.230 The Court concluded 
that PTAB’s institution decision was nonappealable and that USPTO had authority to issue the that PTAB’s institution decision was nonappealable and that USPTO had authority to issue the 
BRC regulation,231 affirming the Federal Circuit’s decision below.232 BRC regulation,231 affirming the Federal Circuit’s decision below.232 
Nonappealability of Institution Decisions. Regarding the no-appeal provision, Cuozzo, a patent Regarding the no-appeal provision, Cuozzo, a patent 
owner, argued that PTAB had improperly instituted an IPR because it invalidated certain of its owner, argued that PTAB had improperly instituted an IPR because it invalidated certain of its 
patent claims on bases only implicitly raised in the petition.233 Thus, Cuozzo argued, the petition patent claims on bases only implicitly raised in the petition.233 Thus, Cuozzo argued, the petition 
had not identified the challenged claims or grounds “with particularity” as required by 35 U.S.C. had not identified the challenged claims or grounds “with particularity” as required by 35 U.S.C. 
§ 312(a)(3).234§ 312(a)(3).234
 
The Supreme Court held that the no-appeal provision rendered PTAB’s decision to institute 
The Supreme Court held that the no-appeal provision rendered PTAB’s decision to institute 
nonappealable.235 While the Supreme Court recognized a “‘strong presumption’ in favor of nonappealable.235 While the Supreme Court recognized a “‘strong presumption’ in favor of 
judicial review” that could only “be overcome by ‘clear and convincing’ indications” from judicial review” that could only “be overcome by ‘clear and convincing’ indications” from 
Congress, it held that the language in Section 314(d) met that standard.236 To hold otherwise, the Congress, it held that the language in Section 314(d) met that standard.236 To hold otherwise, the 
Court reasoned, would undercut the congressional objective of allowing USPTO to revisit Court reasoned, would undercut the congressional objective of allowing USPTO to revisit 
patentability determinations.237 Specifically, the Court doubted that Congress would have given patentability determinations.237 Specifically, the Court doubted that Congress would have given 
USPTO these review powers if it “thought that the agency’s final decision could be unwound USPTO these review powers if it “thought that the agency’s final decision could be unwound 
under some minor statutory technicality related to its preliminary decision to institute [an under some minor statutory technicality related to its preliminary decision to institute [an 
IPR].”238 IPR].”238 
Nevertheless, the Supreme Court indicated that Section 314(d)’s scope is not boundless. The 
Nevertheless, the Supreme Court indicated that Section 314(d)’s scope is not boundless. The 
Court cautioned that the no-appeal provision “applies where the grounds for attacking the Court cautioned that the no-appeal provision “applies where the grounds for attacking the 
 
 
229 35 U.S.C. § 314(d). 
229 35 U.S.C. § 314(d). 
230 230 
Cuozzo, 579 U.S. at 265–66.  , 579 U.S. at 265–66.  
231 231 
See id. at 266.  at 266. 
232 232 
See id. at 283.  at 283. 
233 233 
See id. at 270.  at 270. 
234 234 
See id. . 
235 235 
See id. at 271. at 271. 
236 236 
Id. at 273–74 (quoting Block v. Cmty. Nutrition Inst., 467 U.S. 340, 349–50 (1984)).  at 273–74 (quoting Block v. Cmty. Nutrition Inst., 467 U.S. 340, 349–50 (1984)). 
237 237 
See id. at 272.  at 272. 
238 238 
Id. . 
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decision to institute [an IPR] consist of questions that are closely tied to the application and 
decision to institute [an IPR] consist of questions that are closely tied to the application and 
interpretation of statutes related to the Patent Office’s decision to initiate [IPR].”239 Thus, for interpretation of statutes related to the Patent Office’s decision to initiate [IPR].”239 Thus, for 
instance, Section 314(d) bars judicial review where a patent holder challenges PTAB’s instance, Section 314(d) bars judicial review where a patent holder challenges PTAB’s 
determination that the petition shows a “reasonable likelihood” of success.240 determination that the petition shows a “reasonable likelihood” of success.240 
By contrast, the Court stated that it was not deciding whether the no-appeal provision would 
By contrast, the Court stated that it was not deciding whether the no-appeal provision would 
apply to “appeals that implicate constitutional questions, that depend on other less closely related apply to “appeals that implicate constitutional questions, that depend on other less closely related 
statutes, or that present other questions of interpretation that reach, in terms of scope and impact, statutes, or that present other questions of interpretation that reach, in terms of scope and impact, 
well beyond ‘this section.’”241 The Court also indicated that “shenanigans” where PTAB acted well beyond ‘this section.’”241 The Court also indicated that “shenanigans” where PTAB acted 
beyond its statutory jurisdiction would be reviewable.242 (As explained below, the Court would beyond its statutory jurisdiction would be reviewable.242 (As explained below, the Court would 
revisit the scope of Section 314(d)’s scope four years later, in revisit the scope of Section 314(d)’s scope four years later, in 
Thryv, Inc. v. Click-To-Call 
Technologies, LP.243) .243) 
Justice Alito, dissenting in part and joined by Justice Sotomayor, argued that Section 314(d) did 
Justice Alito, dissenting in part and joined by Justice Sotomayor, argued that Section 314(d) did 
not overcome the presumption against judicial review.244 Justice Alito argued that Section 314(d) not overcome the presumption against judicial review.244 Justice Alito argued that Section 314(d) 
should be read solely as precluding a party from appealing directly from the institution decision should be read solely as precluding a party from appealing directly from the institution decision 
itself, while permitting a party to seek judicial review of the institution decision after PTAB itself, while permitting a party to seek judicial review of the institution decision after PTAB 
issues its final written decision in the IPR.245 issues its final written decision in the IPR.245 
USPTO Authority for the BRC Claim Construction Standard. Turning to claim construction,  Turning to claim construction, 
the Court held that the AIA’s provision giving USPTO authority to issue regulations “establishing the Court held that the AIA’s provision giving USPTO authority to issue regulations “establishing 
and governing [IPR]” allowed it to issue a regulation adopting the BRC standard.246 Since the and governing [IPR]” allowed it to issue a regulation adopting the BRC standard.246 Since the 
AIA did not specify the claim construction standard to be used in IPR, the Court held that, as a AIA did not specify the claim construction standard to be used in IPR, the Court held that, as a 
matter of matter of 
Chevron deference, USPTO was permitted to adopt reasonable rules to fill that statutory  deference, USPTO was permitted to adopt reasonable rules to fill that statutory 
“gap.”247 The Court concluded that adopting the BRC standard was reasonable, explaining that “gap.”247 The Court concluded that adopting the BRC standard was reasonable, explaining that 
USPTO has used this standard in other contexts for many years and that this standard protects the USPTO has used this standard in other contexts for many years and that this standard protects the 
public by helping prevent patentees from “tying up too much knowledge.”248 The Court rejected public by helping prevent patentees from “tying up too much knowledge.”248 The Court rejected 
Cuozzo’s argument that PTAB was required to use the same claim construction standard used by Cuozzo’s argument that PTAB was required to use the same claim construction standard used by 
district courts, noting that IPR is “more like a specialized agency proceeding” than a judicial district courts, noting that IPR is “more like a specialized agency proceeding” than a judicial 
proceeding in some respects and is meant to serve a public interest in keeping “‘patent proceeding in some respects and is meant to serve a public interest in keeping “‘patent 
monopolies . . . within their legitimate scope.’”249 monopolies . . . within their legitimate scope.’”249 
In a concurring opinion, Justice Thomas argued that 
In a concurring opinion, Justice Thomas argued that 
Chevron deference was unnecessary to  deference was unnecessary to 
resolve the BRC question, since the AIA “contains an express and clear conferral of authority to resolve the BRC question, since the AIA “contains an express and clear conferral of authority to 
the Patent Office to promulgate rules governing its own proceedings,” and the rule adopting the the Patent Office to promulgate rules governing its own proceedings,” and the rule adopting the 
BRC standard was not “‘arbitrary, capricious, an abuse of discretion, or otherwise not in BRC standard was not “‘arbitrary, capricious, an abuse of discretion, or otherwise not in 
accordance with law’” under the Administrative Procedure Act.250  accordance with law’” under the Administrative Procedure Act.250  
 
 
239 
239 
Id. at 274–75.  at 274–75. 
240 240 
Id. (citing 35 U.S.C. § 314(a)).  (citing 35 U.S.C. § 314(a)). 
241 241 
Id. at 275. . at 275. 
242 242 
Id. . 
243 590 U.S. 45 (2020). 243 590 U.S. 45 (2020). 
244 244 
Cuozzo, 579 U.S. at 387 (Alito, J., concurring in part and dissenting in part). , 579 U.S. at 387 (Alito, J., concurring in part and dissenting in part). 
245 245 
See id. at 291.  at 291. 
246 246 
Id. at 276 (quoting 35 U.S.C. § 316(a)(4)). . at 276 (quoting 35 U.S.C. § 316(a)(4)). 
247 247 
Id. at 276–77 (citing Chevron U.S.A. Inc. v. Nat. Res. Def. Council, Inc.. at 276–77 (citing Chevron U.S.A. Inc. v. Nat. Res. Def. Council, Inc.
, 467 U.S. 837 (1984)).  467 U.S. 837 (1984)). 
248 248 
See id. at 281.  at 281. 
249 249 
Id. at 278–80 (quoting Precision Instrument Mfg. Co. v. Auto. Maint. Mach. Co., 324 U.S. 806, 816 (1945)).  at 278–80 (quoting Precision Instrument Mfg. Co. v. Auto. Maint. Mach. Co., 324 U.S. 806, 816 (1945)). 
250 250 
Id. at 286–87 (Thomas, J., concurring) (quoting 5 U.S.C. § 706(2)(A)).  at 286–87 (Thomas, J., concurring) (quoting 5 U.S.C. § 706(2)(A)). 
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SAS Institute, Inc. v. Iancu 
In the 2018 decision 
In the 2018 decision 
SAS Institute, Inc. v. Iancu,251 the Supreme Court held that the AIA did not ,251 the Supreme Court held that the AIA did not 
permit a PTAB practice called “partial institution,” whereby PTAB could institute an IPR for permit a PTAB practice called “partial institution,” whereby PTAB could institute an IPR for 
some but not all patent claims challenged in a petition.252 Under the holding in some but not all patent claims challenged in a petition.252 Under the holding in 
SAS, PTAB must , PTAB must 
follow an all-or-nothing approach to institution decisions, either denying institution entirely or follow an all-or-nothing approach to institution decisions, either denying institution entirely or 
instituting an IPR on all of the claims the petitioner challenged.253 In other words, PTAB may not instituting an IPR on all of the claims the petitioner challenged.253 In other words, PTAB may not 
selectively “weed out” challenges to certain claims at the institution stage.  selectively “weed out” challenges to certain claims at the institution stage.  
The case began when SAS petitioned PTAB to institute an IPR on all 16 claims of another 
The case began when SAS petitioned PTAB to institute an IPR on all 16 claims of another 
company’s software patent.254 Based on a USPTO regulation allowing “partial institution,” PTAB company’s software patent.254 Based on a USPTO regulation allowing “partial institution,” PTAB 
instituted an IPR as to nine of those claims, ultimately finding eight of them unpatentable.255 On instituted an IPR as to nine of those claims, ultimately finding eight of them unpatentable.255 On 
appeal to the Federal Circuit, SAS argued that the AIA required PTAB to decide the patentability appeal to the Federal Circuit, SAS argued that the AIA required PTAB to decide the patentability 
of all of the claims challenged in the petition once it instituted an IPR, but the Federal Circuit of all of the claims challenged in the petition once it instituted an IPR, but the Federal Circuit 
rejected this argument.256 rejected this argument.256 
The Supreme Court’s opinion, by Justice Gorsuch, held that the plain text of 35 U.S.C. § 318(a) 
The Supreme Court’s opinion, by Justice Gorsuch, held that the plain text of 35 U.S.C. § 318(a) 
prohibited partial institution.257 Section 318(a) provides: “If an [IPR] is instituted and not prohibited partial institution.257 Section 318(a) provides: “If an [IPR] is instituted and not 
dismissed under this chapter, the [PTAB] shall issue a final written decision with respect to the dismissed under this chapter, the [PTAB] shall issue a final written decision with respect to the 
patentability of any patent claim challenged by the petitioner.”258 The Court held that “any” in this patentability of any patent claim challenged by the petitioner.”258 The Court held that “any” in this 
context implies “every,” requiring PTAB to resolve the patentability of every claim challenged in context implies “every,” requiring PTAB to resolve the patentability of every claim challenged in 
the petition if it decides to institute an IPR.259 The Court reasoned that other statutory features the petition if it decides to institute an IPR.259 The Court reasoned that other statutory features 
supported this reading of Section 318(a), including the fact that the AIA does not permit PTAB to supported this reading of Section 318(a), including the fact that the AIA does not permit PTAB to 
institute an IPR of its own initiative and that IPR utilizes a “party-directed, adversarial institute an IPR of its own initiative and that IPR utilizes a “party-directed, adversarial 
process.”260 Further, the Court held that Section 318(a) is unambiguous, foreclosing any possible process.”260 Further, the Court held that Section 318(a) is unambiguous, foreclosing any possible 
deference to PTAB’s interpretation of the statute.261 In short, the Court held, while PTAB deference to PTAB’s interpretation of the statute.261 In short, the Court held, while PTAB 
generally has discretion “generally has discretion “
whether to institute review” if the petitioner shows a reasonable  to institute review” if the petitioner shows a reasonable 
likelihood of success on at least one patent claim, PTAB does not have discretion “regarding likelihood of success on at least one patent claim, PTAB does not have discretion “regarding 
what  claim that review will encompass.”262  claim that review will encompass.”262  
Four Justices dissented from the Court’s opinion. Justice Ginsburg authored one dissenting 
Four Justices dissented from the Court’s opinion. Justice Ginsburg authored one dissenting 
opinion, arguing that the Court’s holding would needlessly waste PTAB’s resources.263 Justice opinion, arguing that the Court’s holding would needlessly waste PTAB’s resources.263 Justice 
Ginsburg reasoned that, since PTAB is never required to institute an IPR, PTAB could accomplish Ginsburg reasoned that, since PTAB is never required to institute an IPR, PTAB could accomplish 
the same result as partial institution—albeit less efficiently—by denying institution and the same result as partial institution—albeit less efficiently—by denying institution and 
encouraging the petitioner to file a new petition challenging only a subset of the same claims.264  encouraging the petitioner to file a new petition challenging only a subset of the same claims.264  
 
 
251 138 S. Ct. 1348 (2018). 
251 138 S. Ct. 1348 (2018). 
252 252 
See id. at 1354.   at 1354.  
253 253 
See id. at 1353.  at 1353. 
254 254 
See id. at 1354.  at 1354. 
255 255 
See id. . 
256 256 
See id. . 
257 257 
See id. . 
258 35 U.S.C. § 318(a). 258 35 U.S.C. § 318(a). 
259 259 
See  SAS, 138 S. Ct. at 1354. , 138 S. Ct. at 1354. 
260 260 
Id. at 1355.  at 1355. 
261 261 
See id. at 1358 (discussing Chevron U.S.A. Inc. v. Nat. Res. Def. Council, Inc., 467 U.S. 837 (1984)).  at 1358 (discussing Chevron U.S.A. Inc. v. Nat. Res. Def. Council, Inc., 467 U.S. 837 (1984)). 
262 262 
Id. at 1356.at 1356.
   263 263 
Id. at 1360 (Ginsburg, J., dissenting).  at 1360 (Ginsburg, J., dissenting).  
264 264 
See id. . 
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In a second dissenting opinion, Justice Breyer argued that Section 318(a) is ambiguous, requiring 
In a second dissenting opinion, Justice Breyer argued that Section 318(a) is ambiguous, requiring 
the Court to defer to PTAB’s reasonable interpretation of the statute under the Court to defer to PTAB’s reasonable interpretation of the statute under 
Chevron.265 Justice .265 Justice 
Breyer reasoned that the phrase “any patent claim challenged by the petitioner” could refer either Breyer reasoned that the phrase “any patent claim challenged by the petitioner” could refer either 
to challenges made in the petition or to challenges that remain once the IPR instituted.266 Justice to challenges made in the petition or to challenges that remain once the IPR instituted.266 Justice 
Breyer further contended that PTAB’s resolution of this ambiguity, allowing “partial institution,” Breyer further contended that PTAB’s resolution of this ambiguity, allowing “partial institution,” 
was reasonable and entitled to deference.267 was reasonable and entitled to deference.267 
Return Mail, Inc. v. U.S. Postal Service 
In 2019, the Supreme Court decided 
In 2019, the Supreme Court decided 
Return Mail, Inc. v. U.S. Postal Service,268 holding that the ,268 holding that the 
AIA does not permit governmental entities to petition for AIA proceedings (i.e., IPR, PGR, or AIA does not permit governmental entities to petition for AIA proceedings (i.e., IPR, PGR, or 
CBM review).269 This holding has significance for scenarios in which the government—or certain CBM review).269 This holding has significance for scenarios in which the government—or certain 
private parties acting on the government’s behalf, such as government contractors—might be private parties acting on the government’s behalf, such as government contractors—might be 
accused of patent infringement. accused of patent infringement. 
Return Mail, Inc. owned a patent on a method for processing undeliverable mail.270 Asserting that 
Return Mail, Inc. owned a patent on a method for processing undeliverable mail.270 Asserting that 
the U.S. Postal Service infringed this patent, Return Mail sued the Postal Service in the U.S. the U.S. Postal Service infringed this patent, Return Mail sued the Postal Service in the U.S. 
Court of Federal Claims under 28 U.S.C. § 1498.271 Section 1498 allows a patent owner to sue the Court of Federal Claims under 28 U.S.C. § 1498.271 Section 1498 allows a patent owner to sue the 
United States in the Court of Federal Claims when the patented invention “is used or United States in the Court of Federal Claims when the patented invention “is used or 
manufactured by or for the United States without license of the owner thereof or lawful right to manufactured by or for the United States without license of the owner thereof or lawful right to 
use or manufacture the same.”272 Section 1498 allows a patent owner—such as Return Mail—to use or manufacture the same.”272 Section 1498 allows a patent owner—such as Return Mail—to 
recover the “reasonable and entire compensation for such use and manufacture,” as well as costs recover the “reasonable and entire compensation for such use and manufacture,” as well as costs 
and attorneys’ fees in some cases.273  and attorneys’ fees in some cases.273  
In response to Return Mail’s pre-suit infringement accusations, the Postal Service petitioned 
In response to Return Mail’s pre-suit infringement accusations, the Postal Service petitioned 
USPTO for ex parte reexamination of the asserted patent.274 USPTO conducted an ex parte USPTO for ex parte reexamination of the asserted patent.274 USPTO conducted an ex parte 
reexamination and confirmed the validity of the patent (albeit by substituting claims).275 Then, reexamination and confirmed the validity of the patent (albeit by substituting claims).275 Then, 
after Return Mail had filed its infringement suit in the Court of Federal Claims, the Postal Service after Return Mail had filed its infringement suit in the Court of Federal Claims, the Postal Service 
petitioned for CBM review of the patent.276 PTAB initiated a CBM review and ruled that the petitioned for CBM review of the patent.276 PTAB initiated a CBM review and ruled that the 
 
 
265 
265 
Id. (Breyer, J., dissenting) (citing Chevron, 467 U.S. at 842–43).  (Breyer, J., dissenting) (citing Chevron, 467 U.S. at 842–43). 
266 266 
Id. at 1361 (Breyer, J., dissenting). at 1361 (Breyer, J., dissenting). 
267 267 
See id. at 264.   at 264.  
268 139 S. Ct. 1853 (2019). 268 139 S. Ct. 1853 (2019). 
269 269 
See id. at 1867.  at 1867. 
270 270 
See id. at 1861.  at 1861. 
271 271 
See id. . 
272 28 U.S.C. § 1498(a). 272 28 U.S.C. § 1498(a). 
273 273 
Id. (permitting award of costs and fees “if the owner is an independent inventor, a nonprofit organization, or an (permitting award of costs and fees “if the owner is an independent inventor, a nonprofit organization, or an 
entity that had no more than 500 employees at any time during the 5-year period preceding the use or manufacture”).entity that had no more than 500 employees at any time during the 5-year period preceding the use or manufacture”).
 
Section 1498 provides that patent owners may bring such claims against the United States not only when the Section 1498 provides that patent owners may bring such claims against the United States not only when the 
government itself uses or manufactures the invention, but also when private parties use or manufacture the invention government itself uses or manufactures the invention, but also when private parties use or manufacture the invention 
“for” the government with its “authorization or consent.” “for” the government with its “authorization or consent.” 
Id. (“[T]he use or manufacture of an invention described in . (“[T]he use or manufacture of an invention described in 
and covered by a patent of the United States by a contractor, a subcontractor, or any person, firm, or corporation for the and covered by a patent of the United States by a contractor, a subcontractor, or any person, firm, or corporation for the 
Government and with the authorization or consent of the Government, shall be construed as use or manufacture for the Government and with the authorization or consent of the Government, shall be construed as use or manufacture for the 
United States.”). United States.”). 
274 274 
See Return Mail, 139 S. Ct. at 1861. , 139 S. Ct. at 1861. 
275 275 
See id. . 
276 276 
See id. . 
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patent was invalid because it was directed to ineligible subject matter. On appeal, the Federal 
patent was invalid because it was directed to ineligible subject matter. On appeal, the Federal 
Circuit affirmed PTAB’s decision.277 Circuit affirmed PTAB’s decision.277 
At the Supreme Court, 
At the Supreme Court, 
Return Mail hinged on whether, as a matter of statutory interpretation, the  hinged on whether, as a matter of statutory interpretation, the 
government is a “person” eligible to petition for CBM review or other AIA proceedings.278 The government is a “person” eligible to petition for CBM review or other AIA proceedings.278 The 
AIA allows “a person who is not the owner of a patent” to petition for IPR, PGR, and CBM AIA allows “a person who is not the owner of a patent” to petition for IPR, PGR, and CBM 
review,279 but it does not define the word “person.”280  review,279 but it does not define the word “person.”280  
The Court, in an opinion by Justice Sotomayor, held that “person” as used in the AIA does not 
The Court, in an opinion by Justice Sotomayor, held that “person” as used in the AIA does not 
include the government and its agencies.281 To reach this holding, the Court applied a include the government and its agencies.281 To reach this holding, the Court applied a 
“longstanding interpretive presumption” that the word “person” does not include the “longstanding interpretive presumption” that the word “person” does not include the 
government.282 The Court noted that Congress itself had adopted this presumption283 in a 1947 government.282 The Court noted that Congress itself had adopted this presumption283 in a 1947 
law (the Dictionary Act) providing that specific words, as used in acts of Congress, should be law (the Dictionary Act) providing that specific words, as used in acts of Congress, should be 
interpreted according to definitions provided in the Dictionary Act “unless the context indicates interpreted according to definitions provided in the Dictionary Act “unless the context indicates 
otherwise.”284 The Dictionary Act’s definition of a “person,” the Court noted, included certain otherwise.”284 The Dictionary Act’s definition of a “person,” the Court noted, included certain 
corporate entities but not the government.285  corporate entities but not the government.285  
The Court rejected the Postal Service’s argument that Congress must have intended the 
The Court rejected the Postal Service’s argument that Congress must have intended the 
government to be able to petition for AIA proceedings since Congress has made the government government to be able to petition for AIA proceedings since Congress has made the government 
liable to pay compensation for patent infringement under Section 1498.286 In response to this liable to pay compensation for patent infringement under Section 1498.286 In response to this 
argument, the Court noted that the government’s potential liability under Section 1498 is less argument, the Court noted that the government’s potential liability under Section 1498 is less 
severe than that of ordinary infringers in a civil suit, and the government may still assert severe than that of ordinary infringers in a civil suit, and the government may still assert 
invalidity as a defense in any Section 1498 lawsuit and petition for non-AIA proceedings such as invalidity as a defense in any Section 1498 lawsuit and petition for non-AIA proceedings such as 
ex parte reexamination.287 ex parte reexamination.287 
Justice Breyer issued a dissenting opinion that was joined by Justices Ginsburg and Kagan.288 The 
Justice Breyer issued a dissenting opinion that was joined by Justices Ginsburg and Kagan.288 The 
dissent argued that the presumption against interpreting “person” in the AIA to include the dissent argued that the presumption against interpreting “person” in the AIA to include the 
government was weakened by the fact that certain other uses of “person” in the Patent Act (e.g., government was weakened by the fact that certain other uses of “person” in the Patent Act (e.g., 
those referring to eligibility to obtain a patent) include the government.289 The dissent also argued those referring to eligibility to obtain a patent) include the government.289 The dissent also argued 
that allowing the government to petition for AIA proceedings would better serve Congress’s that allowing the government to petition for AIA proceedings would better serve Congress’s 
purpose in enacting the AIA and that it would be anomalous for Congress not to allow the purpose in enacting the AIA and that it would be anomalous for Congress not to allow the 
 
 
277 
277 
See id. . 
278 278 
See id. . 
279 279 
Id. at 1860;  at 1860; 
see 35 U.S.C. §§ 311(a) (IPR), 321(a) (PGR); Pub. L. No. 112-29 § 18(a)(1), (B), 125 Stat. 330 (2011)  35 U.S.C. §§ 311(a) (IPR), 321(a) (PGR); Pub. L. No. 112-29 § 18(a)(1), (B), 125 Stat. 330 (2011) 
(providing that CBM review “shall be regarded as, and shall employ the standards and procedures of, a [PGR]” and that (providing that CBM review “shall be regarded as, and shall employ the standards and procedures of, a [PGR]” and that 
“[a] person may not file a petition for [CBM review] unless the person or the person’s real party in interest or privy has “[a] person may not file a petition for [CBM review] unless the person or the person’s real party in interest or privy has 
been sued . . . or . . . charged with infringement”). been sued . . . or . . . charged with infringement”). 
280 
280 
See Return Mail, 139 S. Ct. at 1861. , 139 S. Ct. at 1861. 
281 281 
See id. at 1867.  at 1867. 
282 282 
Id. at 1862–63 (quoting Vt. Agency of Nat. Res. v. United States ex rel. Stevens, 529 U.S. 765, 780–81 (2000)).  at 1862–63 (quoting Vt. Agency of Nat. Res. v. United States ex rel. Stevens, 529 U.S. 765, 780–81 (2000)). 
283 283 
See Return Mail, 139 S. Ct. at 1863. , 139 S. Ct. at 1863. 
284 1 U.S.C. § 1. 284 1 U.S.C. § 1. 
285 285 
See id. (“[T]he words ‘person’ and ‘whoever’ include corporations, companies, associations, firms, partnerships,  (“[T]he words ‘person’ and ‘whoever’ include corporations, companies, associations, firms, partnerships, 
societies, and joint stock companies, as well as individuals . . . .”). societies, and joint stock companies, as well as individuals . . . .”). 
286 
286 
See Return Mail, 139 S. Ct. at 1866–67. , 139 S. Ct. at 1866–67. 
287 287 
See id. . 
288 288 
See id. at 1868–72 (Breyer, J., dissenting).  at 1868–72 (Breyer, J., dissenting). 
289 289 
See id. at 1868–70.  at 1868–70. 
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government to petition for AIA review while allowing the government to be sued for patent 
government to petition for AIA review while allowing the government to be sued for patent 
infringement and to avail itself of other USPTO invalidity proceedings.290  infringement and to avail itself of other USPTO invalidity proceedings.290  
Thryv, Inc. v. Click-to-Call Technologies, LP 
In 2020, the Supreme Court again considered Section 314(d)’s no-appeal provision in 
In 2020, the Supreme Court again considered Section 314(d)’s no-appeal provision in 
Thryv, Inc. 
v. Click-to-Call Technologies, LP.291 .291 
Click-to-Call concerned the “time-bar” provision of 35  concerned the “time-bar” provision of 35 
U.S.C. § 315(b), which requires petitioners to file an IPR no more one year after they are sued for U.S.C. § 315(b), which requires petitioners to file an IPR no more one year after they are sued for 
infringement of the patent.292 The Court, in an opinion by Justice Ginsburg, held that infringement of the patent.292 The Court, in an opinion by Justice Ginsburg, held that 
Section 314(d) bars judicial review of PTAB determinations regarding Section 315(b)’s time Section 314(d) bars judicial review of PTAB determinations regarding Section 315(b)’s time 
bar.293  bar.293  
The respondent, Click-to-Call Technologies, LP, owned a patent that Thryv, Inc. challenged via an 
The respondent, Click-to-Call Technologies, LP, owned a patent that Thryv, Inc. challenged via an 
IPR petition filed in 2013.294 Click-to-Call claimed the petition was untimely, arguing that IPR petition filed in 2013.294 Click-to-Call claimed the petition was untimely, arguing that 
Section 315(b)’s one-year clock had begun to run in 2001, when Thryv’s predecessor was sued Section 315(b)’s one-year clock had begun to run in 2001, when Thryv’s predecessor was sued 
for infringement of the patent.295 PTAB, however, ruled that this infringement suit did not trigger for infringement of the patent.295 PTAB, however, ruled that this infringement suit did not trigger 
the one-year clock because it had been dismissed without prejudice.296 the one-year clock because it had been dismissed without prejudice.296 
The Court found 
The Court found 
Cuozzo’s holding—that Section 314(d) bars review of “matters ‘closely tied to ’s holding—that Section 314(d) bars review of “matters ‘closely tied to 
the application and interpretation of statutes related to’ the institution decision”—controlling in the application and interpretation of statutes related to’ the institution decision”—controlling in 
Thryv, since the Section 315(b) time bar is an “integral” condition on institution.297 The Court , since the Section 315(b) time bar is an “integral” condition on institution.297 The Court 
also determined that the “purpose and design” of the statute creating IPR reinforces the also determined that the “purpose and design” of the statute creating IPR reinforces the 
conclusion that the no-appeal provision applies to the time bar because IPR “sought to weed out conclusion that the no-appeal provision applies to the time bar because IPR “sought to weed out 
bad patent claims,” and that allowing review of the time bar would permit the continued bad patent claims,” and that allowing review of the time bar would permit the continued 
enforcement of patents held to be invalid.298 enforcement of patents held to be invalid.298 
The Court rejected Click-to-Call’s arguments that Section 314(d) does not apply to time-bar 
The Court rejected Click-to-Call’s arguments that Section 314(d) does not apply to time-bar 
determinations, including its attempt to read Section 314(d) as limited to the initial merits determinations, including its attempt to read Section 314(d) as limited to the initial merits 
determination.299 The Court found this argument foreclosed by determination.299 The Court found this argument foreclosed by 
Cuozzo and inconsistent with  and inconsistent with 
related no-appeal provisions that Congress drew more narrowly. If Congress had intended related no-appeal provisions that Congress drew more narrowly. If Congress had intended 
Section 314(d)’s scope to be narrower, the Court reasoned, it would have used narrower Section 314(d)’s scope to be narrower, the Court reasoned, it would have used narrower 
language.300 Accordingly, the Court vacated and remanded the Federal Circuit’s judgment, with language.300 Accordingly, the Court vacated and remanded the Federal Circuit’s judgment, with 
instructions to dismiss the appeal for lack of jurisdiction.301 instructions to dismiss the appeal for lack of jurisdiction.301 
Justice Gorsuch issued a dissenting opinion that Justice Sotomayor joined in part. Justice Gorsuch 
Justice Gorsuch issued a dissenting opinion that Justice Sotomayor joined in part. Justice Gorsuch 
argued that Section 314(d)’s text indicates that the no-appeal provision applies only to PTAB’s argued that Section 314(d)’s text indicates that the no-appeal provision applies only to PTAB’s 
initial determination on the merits of the petition, not to other determinations.302 Justice Gorsuch initial determination on the merits of the petition, not to other determinations.302 Justice Gorsuch 
contended that contended that 
Cuozzo’s statement to the contrary was “dicta” (i.e., nonbinding language not ’s statement to the contrary was “dicta” (i.e., nonbinding language not 
 
 
290 
290 
See id. at 1870–71.  at 1870–71. 
291 590 U.S. 45 (2020). 291 590 U.S. 45 (2020). 
292 292 
See id. at 47–49. at 47–49. 
293 293 
See id.  .  
294 294 
See id.  295 295 
See id. & n. 4.  & n. 4. 
296 296 
See id. at 47–49. . at 47–49. 
297 297 
Id. at 46 (quoting  at 46 (quoting 
CuozzoCuozzo, 579 U.S. at 273–75). , 579 U.S. at 273–75). 
298 298 
See  id. at 52–54. at 52–54. 
299 299 
See id. at 56–57.  at 56–57. 
300 300 
See id. at 56–59.  at 56–59. 
301 301 
See id. at 60–61.  at 60–61. 
302 302 
See id. at 65–66 (Gorsuch, J., dissenting). at 65–66 (Gorsuch, J., dissenting). 
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necessary to the holding of that case) and should not control the present case.303 Moreover, he 
necessary to the holding of that case) and should not control the present case.303 Moreover, he 
argued that the presumption of judicial review indicates that the no-appeal provision should be argued that the presumption of judicial review indicates that the no-appeal provision should be 
read narrowly to reach only the initial merits determination.304 Justice Gorsuch also opined that read narrowly to reach only the initial merits determination.304 Justice Gorsuch also opined that 
the Court’s precedents interpreting the AIA shifted too much power to USPTO at the expense of the Court’s precedents interpreting the AIA shifted too much power to USPTO at the expense of 
the courts, particularly considering that the USPTO Director is a political appointee.305 Finally, he the courts, particularly considering that the USPTO Director is a political appointee.305 Finally, he 
criticized the Court’s previous decision upholding the IPR’s constitutionality as part of a trend of criticized the Court’s previous decision upholding the IPR’s constitutionality as part of a trend of 
“handing over judicial powers involving the disposition of individual rights to executive agency “handing over judicial powers involving the disposition of individual rights to executive agency 
officials.”306 officials.”306 
Constitutional Challenges to IPR 
While the foregoing cases addressed questions of statutory interpretation of the AIA, the Supreme While the foregoing cases addressed questions of statutory interpretation of the AIA, the Supreme 
Court has also heard two cases challenging aspects of IPR proceedings on constitutional grounds. Court has also heard two cases challenging aspects of IPR proceedings on constitutional grounds. 
In the first of these cases, the Supreme Court upheld the constitutionality of IPR against In the first of these cases, the Supreme Court upheld the constitutionality of IPR against 
arguments that it violates separation-of-powers principles and the constitutional guarantee of jury arguments that it violates separation-of-powers principles and the constitutional guarantee of jury 
trials. In the second case, the Supreme Court invalidated a provision of the AIA that prevented the trials. In the second case, the Supreme Court invalidated a provision of the AIA that prevented the 
USPTO Director from reviewing IPR decisions, holding that it violated the Constitution’s USPTO Director from reviewing IPR decisions, holding that it violated the Constitution’s 
Appointments Clause.  Appointments Clause.  
Oil States Energy Services, LLC v. Greene’s Energy Group, LLC 
In 
In 
Oil States Energy Services, LLC v. Greene’s Energy Group, LLC,307 the Court addressed ,307 the Court addressed 
whether IPR violates Article III or the Seventh Amendment of the Constitution. In whether IPR violates Article III or the Seventh Amendment of the Constitution. In 
Oil States, a , a 
party whose patent claims had been invalidated in IPR argued that IPR was unconstitutional party whose patent claims had been invalidated in IPR argued that IPR was unconstitutional 
because patent rights can be revoked only by an Article III court (e.g., a federal district court), because patent rights can be revoked only by an Article III court (e.g., a federal district court), 
with the right to a jury trial pursuant to the Seventh Amendment.308 The Supreme Court rejected with the right to a jury trial pursuant to the Seventh Amendment.308 The Supreme Court rejected 
this argument.309  this argument.309  
The Supreme Court explained that, while
The Supreme Court explained that, while
 Article III “vests the judicial power of the United Article III “vests the judicial power of the United 
States” in federal courts, proceedings that adjudicate “public rights” do not necessarily involve an States” in federal courts, proceedings that adjudicate “public rights” do not necessarily involve an 
exercise of judicial power.310 This “public rights doctrine” gives Congress “significant latitude” to exercise of judicial power.310 This “public rights doctrine” gives Congress “significant latitude” to 
allow tribunals other than Article III courts to adjudicate public rights.33 The Court held that allow tribunals other than Article III courts to adjudicate public rights.33 The Court held that 
patent rights are public rather than private rights, since patents are created pursuant to statute and patent rights are public rather than private rights, since patents are created pursuant to statute and 
give the owner a “public franchise” or monopoly that prevents the public from practicing the give the owner a “public franchise” or monopoly that prevents the public from practicing the 
claimed invention.311 Since IPRclaimed invention.311 Since IPR
 is “simply a reconsideration” of the initial granting of that public is “simply a reconsideration” of the initial granting of that public 
right312—and since patent claims are granted subject to the possibility that they may be right312—and since patent claims are granted subject to the possibility that they may be 
invalidated in IPR313—the Court held that an issued patent’s validity can constitutionally be invalidated in IPR313—the Court held that an issued patent’s validity can constitutionally be 
 
 
303 
303 
See id. at 75–77.  at 75–77. 
304 304 
See id. at 70–72.  at 70–72. 
305 305 
See id. at 79–81.  at 79–81. 
306 306 
Id. at 77–79;  at 77–79; 
see  infra  “Oil States Energy Services, LLC v. Greene’s Energy Group, LLC.”  307 584 U.S. 325 (2018). 307 584 U.S. 325 (2018). 
308 308 
See id. at 332–34. PTAB is an administrative or legislative court, not an Article III court, because PTAB hears cases  at 332–34. PTAB is an administrative or legislative court, not an Article III court, because PTAB hears cases 
in which the petitioner lacks standing and APJs do not enjoy protections afforded to Article III judges such as lifetime in which the petitioner lacks standing and APJs do not enjoy protections afforded to Article III judges such as lifetime 
tenure. tenure. 
See generally CRS Report R43746,  CRS Report R43746, 
Congressional Power to Create Federal Courts: A Legal Overview (2015).  (2015). 
309 
309 
Oil States, 584 U.S. at 344–45. , 584 U.S. at 344–45. 
310 310 
See id. at 332–35. at 332–35.
 
311 311 
Id. at 334–38.  at 334–38. 
312 312 
Id. at 334–35.  at 334–35. 
313 313 
See id. at 335–37.  at 335–37. 
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determined by PTAB rather than an Article III court. Further, since Congress was permitted to 
determined by PTAB rather than an Article III court. Further, since Congress was permitted to 
assign IPR proceedings to non-Article III tribunal, the Court held that appellants had no right to a assign IPR proceedings to non-Article III tribunal, the Court held that appellants had no right to a 
trial by jury under the Seventh Amendment.314 trial by jury under the Seventh Amendment.314 
Seven Justices joined Justice Thomas’s majority opinion in full, with three of those Justices 
Seven Justices joined Justice Thomas’s majority opinion in full, with three of those Justices 
concurring to express their perspective that private rights may also sometimes be adjudicated by concurring to express their perspective that private rights may also sometimes be adjudicated by 
bodies other than Article III courts.315 Justice Gorsuch, joined by Chief Justice Roberts, bodies other than Article III courts.315 Justice Gorsuch, joined by Chief Justice Roberts, 
dissented.316 Justice Gorsuch argued that, based on historical practice in the United States and dissented.316 Justice Gorsuch argued that, based on historical practice in the United States and 
England, cancelling an issued patent is an exercise of “judicial power”317 that is not comparable England, cancelling an issued patent is an exercise of “judicial power”317 that is not comparable 
to USPTO’s initial decision whether to grant a patent.318 Whereas the majority noted that, prior to to USPTO’s initial decision whether to grant a patent.318 Whereas the majority noted that, prior to 
the creation of PTAB and IPR, Congress had established other non-Article III proceedings to the creation of PTAB and IPR, Congress had established other non-Article III proceedings to 
cancel issued patents since 1980,319 Justice Gorsuch stressed that such proceedings did not exist cancel issued patents since 1980,319 Justice Gorsuch stressed that such proceedings did not exist 
from 1790 (when Congress enacted the first Patent Act) to 1980.320 from 1790 (when Congress enacted the first Patent Act) to 1980.320 
United States v. Arthrex 
In the 2021 case 
In the 2021 case 
United States v. Arthrex,321 the Supreme Court invalidated the provision of the ,321 the Supreme Court invalidated the provision of the 
AIA that prevented the USPTO Director from reviewing APJs’ IPR decisions, holding that this AIA that prevented the USPTO Director from reviewing APJs’ IPR decisions, holding that this 
provision violated the Constitution’s Appointments Clause.322 The Court’s decision in provision violated the Constitution’s Appointments Clause.322 The Court’s decision in 
Arthrex  prompted PTAB to develop an interim process for the Director to review panel decisions—a prompted PTAB to develop an interim process for the Director to review panel decisions—a 
process discussed in the following section of this report.  process discussed in the following section of this report.  
The Appointments Clause sets forth how “Officers of the United States,” such as APJs, may be 
The Appointments Clause sets forth how “Officers of the United States,” such as APJs, may be 
appointed.323 It gives Congress discretion to vest the appointment of “inferior [o]fficers” either in appointed.323 It gives Congress discretion to vest the appointment of “inferior [o]fficers” either in 
“the President alone, in the Courts of Law, or in the Heads of Departments” but requires the “the President alone, in the Courts of Law, or in the Heads of Departments” but requires the 
President to appoint all other officers—whom the Supreme Court refers to as President to appoint all other officers—whom the Supreme Court refers to as 
principal officers——
with the Senate’s advice and consent.324 In with the Senate’s advice and consent.324 In 
Arthrex, a company whose patent had been invalidated , a company whose patent had been invalidated 
in an IPR claimed that APJs’ appointment by the Secretary of Commerce was unconstitutional, in an IPR claimed that APJs’ appointment by the Secretary of Commerce was unconstitutional, 
arguing that APJs were principal officers requiring presidential appointment and Senate arguing that APJs were principal officers requiring presidential appointment and Senate 
confirmation.325 confirmation.325 
The Supreme Court, in an opinion by Chief Justice Roberts, held that the AIA gave APJs 
The Supreme Court, in an opinion by Chief Justice Roberts, held that the AIA gave APJs 
authority that was “incompatible with their appointment by the Secretary to an inferior office.”326 authority that was “incompatible with their appointment by the Secretary to an inferior office.”326 
 
 
314 
314 
See id. at 334–38.  at 334–38. 
315 315 
See id. at 334–38 (Breyer, J., concurring).  at 334–38 (Breyer, J., concurring). 
316 316 
Id. at 345–47 (Gorsuch, J., dissenting). at 345–47 (Gorsuch, J., dissenting). 
317 317 
See id. at 347–54.  at 347–54. 
318 318 
See id. at 354–55.  at 354–55. 
319 319 
See  id. at 354–56.  at 354–56. 
320 320 
See id. at 352–54 (Gorsuch, J., dissenting). The majority and Justice Gorsuch also reached differing interpretations  at 352–54 (Gorsuch, J., dissenting). The majority and Justice Gorsuch also reached differing interpretations 
regarding the extent to which nonjudicial proceedings to cancel patents were an accepted practice under English law at regarding the extent to which nonjudicial proceedings to cancel patents were an accepted practice under English law at 
the time of the framing of the Constitution.the time of the framing of the Constitution.
 Compare  id. at 340–42 (majority opinion, noting practice of vacating  at 340–42 (majority opinion, noting practice of vacating 
patents via petitions to the Privy Council), patents via petitions to the Privy Council), 
with  id. at 351–52 (Gorsuch, J., dissenting, arguing that this practice had  at 351–52 (Gorsuch, J., dissenting, arguing that this practice had 
become a “last resort” by the time of the Constitution). become a “last resort” by the time of the Constitution). 
321 594 U.S. 1 (2021). 321 594 U.S. 1 (2021). 
322 322 
See id. at 24–28.  at 24–28. 
323 323 
See Cong. Rsch. Serv.,  Cong. Rsch. Serv., 
Officer and Non-Officer Appointments, CONSTITUTION ANNOTATED, CONSTITUTION ANNOTATED, 
https://constitution.congress.gov/browse/essay/artII-S2-C2-3-10/ALDE_00013100/ (last visited Mar. 28, 2024). https://constitution.congress.gov/browse/essay/artII-S2-C2-3-10/ALDE_00013100/ (last visited Mar. 28, 2024). 
324 U.S. CONST. art. II, § 2, cl. 2. 
324 U.S. CONST. art. II, § 2, cl. 2. 
325 325 
See  Arthrex, 594 U.S. at 9–14. , 594 U.S. at 9–14. 
326 326 
Id. at 23.  at 23. 
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The AIA, as written, did not subject the APJs’ IPR decisions to “review by a superior executive 
The AIA, as written, did not subject the APJs’ IPR decisions to “review by a superior executive 
officer,” such as the USPTO Director.327 The Court reasoned that only principal officers officer,” such as the USPTO Director.327 The Court reasoned that only principal officers 
nominated by the President and confirmed by the Senate may make “final decision[s] binding the nominated by the President and confirmed by the Senate may make “final decision[s] binding the 
Executive Branch” in administrative adjudications such as IPRs.328 Under the AIA, however, only Executive Branch” in administrative adjudications such as IPRs.328 Under the AIA, however, only 
PTAB itself (not the USPTO Director) could grant rehearing of PTAB decisions, giving APJs the PTAB itself (not the USPTO Director) could grant rehearing of PTAB decisions, giving APJs the 
final word of the executive branch on PTAB’s patentability decisions in IPRs.329 In short, the final word of the executive branch on PTAB’s patentability decisions in IPRs.329 In short, the 
Court held that the structure of PTAB violated the Constitution because it gave inferior officers Court held that the structure of PTAB violated the Constitution because it gave inferior officers 
(APJs) “unreviewable executive power.”330 (APJs) “unreviewable executive power.”330 
Despite this constitutional flaw, the Court did not invalidate the PTAB itself or the administrative 
Despite this constitutional flaw, the Court did not invalidate the PTAB itself or the administrative 
processes created by the AIA. Instead, it concluded that the appropriate remedy was to grant the processes created by the AIA. Instead, it concluded that the appropriate remedy was to grant the 
Director unilateral power to review PTAB decisions.331 Although the AIA specifically insulated Director unilateral power to review PTAB decisions.331 Although the AIA specifically insulated 
PTAB decisions from further review within the executive branch—providing that “[o]nly the PTAB decisions from further review within the executive branch—providing that “[o]nly the 
[PTAB] may grant rehearings”332—the Court severed (or invalidated) this statutory provision to [PTAB] may grant rehearings”332—the Court severed (or invalidated) this statutory provision to 
save the remainder of the statute.333 save the remainder of the statute.333 
Arthrex thus gave the Director “discretion” to rehear PTAB  thus gave the Director “discretion” to rehear PTAB 
decisions.334 The Court reasoned that this remedy was sufficient since APJs are inferior officers decisions.334 The Court reasoned that this remedy was sufficient since APJs are inferior officers 
“[i]n every respect save the insulation of their decisions from review within the Executive “[i]n every respect save the insulation of their decisions from review within the Executive 
Branch.”335 Branch.”335 
Justice Gorsuch joined the majority opinion on the merits but dissented as to the appropriate 
Justice Gorsuch joined the majority opinion on the merits but dissented as to the appropriate 
remedy.336 He argued that the Court’s “severance” doctrine—in which the Court excises part of a remedy.336 He argued that the Court’s “severance” doctrine—in which the Court excises part of a 
statute to cure a constitutional problem—is inappropriate when there is more than “one possible statute to cure a constitutional problem—is inappropriate when there is more than “one possible 
way” to cure the constitutional problem and Congress has not provided any specific direction.337 way” to cure the constitutional problem and Congress has not provided any specific direction.337 
Justice Gorsuch argued the Court should instead decline to enforce the statute—in this case, Justice Gorsuch argued the Court should instead decline to enforce the statute—in this case, 
allowing challengers to vacate PTAB decisions until Congress fixed the constitutional allowing challengers to vacate PTAB decisions until Congress fixed the constitutional 
problem338—to avoid guessing “what a past Congress would have done.”339  problem338—to avoid guessing “what a past Congress would have done.”339  
Justice Thomas, joined in part by Justices Breyer, Sotomayor, and Kagan, dissented as to the 
Justice Thomas, joined in part by Justices Breyer, Sotomayor, and Kagan, dissented as to the 
merits of the Appointments Clause question, arguing that the PTAB’s structure was consistent merits of the Appointments Clause question, arguing that the PTAB’s structure was consistent 
with the Constitution.340 Justice Thomas argued APJs are inferior officers because they are “lower with the Constitution.340 Justice Thomas argued APJs are inferior officers because they are “lower 
in rank to at least two different officers”—the Director and the Secretary341—and because the in rank to at least two different officers”—the Director and the Secretary341—and because the 
Director has a number of tools to supervise and control APJs, making them “functionally” Director has a number of tools to supervise and control APJs, making them “functionally” 
inferior.342 For instance, the AIA allows the Director to decide whether to institute an IPR, control inferior.342 For instance, the AIA allows the Director to decide whether to institute an IPR, control 
 
 
327 
327 
Id. at 14.  at 14. 
328 328 
Id. at 23.  at 23. 
329 329 
See id. at 23–27 (discussing 35 U.S.C. § 6(c)).  at 23–27 (discussing 35 U.S.C. § 6(c)). 
330 330 
Id. at 18–19.  at 18–19. 
331 331 
See id. at 23–28.   at 23–28.  
332 35 U.S.C. § 6(c). 332 35 U.S.C. § 6(c). 
333 333 
Arthrex, 594 U.S. at 23–25. , 594 U.S. at 23–25. 
334 334 
Id. at 27–28.  at 27–28. 
335 335 
Id. at 23–25.  at 23–25. 
336 336 
See  id. at 27–28 (Gorsuch, J., dissenting). at 27–28 (Gorsuch, J., dissenting). 
337 337 
Id. at 30–32.  at 30–32. 
338 338 
See id. . 
339 339 
Id. at 34–35.  at 34–35. 
340 340 
See  id. at 43–46 (Thomas, J., dissenting).  at 43–46 (Thomas, J., dissenting). 
341 341 
Id. at 48–50.  at 48–50. 
342 342 
Id. . 
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which APJs are assigned to the panel, and add additional members (including the Director) to 
which APJs are assigned to the panel, and add additional members (including the Director) to 
panels.343  panels.343  
Justice Breyer, joined by Justices Sotomayor and Kagan, issued a separate opinion dissenting on 
Justice Breyer, joined by Justices Sotomayor and Kagan, issued a separate opinion dissenting on 
the merits, arguing that the Appointments Clause grants Congress “a degree of leeway”344 and the merits, arguing that the Appointments Clause grants Congress “a degree of leeway”344 and 
that the Court should “take account of . . . why Congress enacted a particular statutory limitation” that the Court should “take account of . . . why Congress enacted a particular statutory limitation” 
and consider the “practical consequences” of that choice.345 Here, Justice Breyer argued, the and consider the “practical consequences” of that choice.345 Here, Justice Breyer argued, the 
“technical nature of patents, the need for expertise, and the importance of avoiding political “technical nature of patents, the need for expertise, and the importance of avoiding political 
interference” justified Congress’s decision to give APJs a degree of independence.346 interference” justified Congress’s decision to give APJs a degree of independence.346 
Current Debates and Proposed Reforms 
PTAB has administeredPTAB has administered
 AIA post-grant proceedings for more than a decade. As PTAB has gained  post-grant proceedings for more than a decade. As PTAB has gained 
experience with these new types of proceedings—and developed rules, operating procedures, experience with these new types of proceedings—and developed rules, operating procedures, 
guidelines, and precedential decisions for them—several issues have attracted attention and guidelines, and precedential decisions for them—several issues have attracted attention and 
differing views from stakeholders. Some of these issues include the proper role of the USPTO differing views from stakeholders. Some of these issues include the proper role of the USPTO 
Director and PTAB management in PTAB proceedings (especially following Director and PTAB management in PTAB proceedings (especially following 
Arthrex); who ); who 
should be able to file petitions; the proper standards for proving invalidity and for claim should be able to file petitions; the proper standards for proving invalidity and for claim 
construction; and the circumstances when PTAB should deny institution of an IPR.  construction; and the circumstances when PTAB should deny institution of an IPR.  
This section of the report explains PTAB’s current practices in these areas and selected proposed 
This section of the report explains PTAB’s current practices in these areas and selected proposed 
reformsreforms
. Two notable proposed reforms introduced in 2023 that would address some of these issues are, including the Promoting and Respecting Economically Vital American Innovation Leadership Act  the Promoting and Respecting Economically Vital American Innovation Leadership Act 
(PREVAIL Act), introduced in the 118th Congress as S. 2220,347 and (PREVAIL Act), introduced in the 118th Congress as S. 2220,347 and 
an Advanced Notice of Proposed Rulemaking published by USPTO on April 21, 2023 (the ANPRM).348 While both proposed reforms would make various changes to PTAB’s discretionary denial practices, the PREVAIL Act would make changes in all of the areas noted above—including changes which can only be made via legislation.several proposed rulemaking notices published by USPTO.348 This section discusses how selected provisions in the  This section discusses how selected provisions in the 
ANPRM and the PREVAIL ActPREVAIL Act and USPTO’s proposed rules would reform  would reform 
somecertain aspects of PTAB.349  aspects of PTAB.349 
What Roles Do the USPTO Director and PTAB Management Play 
in PTAB Decisions? 
Interim Director Review Process 
As discussed above, the Supreme Court’s 2021 
As discussed above, the Supreme Court’s 2021 
Arthrex decision gave the USPTO Director  decision gave the USPTO Director 
unilateral power to review PTAB’s decisions and invalidated a provision of the AIA to the extent unilateral power to review PTAB’s decisions and invalidated a provision of the AIA to the extent 
 
 
343 
343 
See id. at 50–53.  at 50–53. 
344 344 
Id. at 38 (Breyer, J., dissenting).  at 38 (Breyer, J., dissenting). 
345 345 
Id. at 41.  at 41. 
346 346 
Id. at 41.  at 41. 
347 347 
See PREVAIL Act, S. 2220, 118th Cong. (2023). An identical bill has been introduced in the U.S. House of  PREVAIL Act, S. 2220, 118th Cong. (2023). An identical bill has been introduced in the U.S. House of 
Representatives as H.R. 4370, 118th Cong. (2023). Representatives as H.R. 4370, 118th Cong. (2023). 
348
348
 See Patent Trial and Appeal Board Rules of Practice for Briefing Discretionary Denial Issues, and Rules for 325(d) Considerations, Instituting Parallel and Serial Petitions, and Termination Due to Settlement Agreement, 89 Fed. Reg. 28693 (Apr. 19, 2024) [hereinafter Discretionary Denial NPRM]; Rules Governing Director Review of Patent Trial and Appeal Board Decisions, 89 Fed. Reg. 26807 (April 16, 2024) [hereinafter Director Review NPRM]; Changes Under Consideration to Discretionary Institution Practices, Petition Word-Count Limits, and Settlement  Changes Under Consideration to Discretionary Institution Practices, Petition Word-Count Limits, and Settlement 
Practices for America Invents Act Trial Proceedings Before the Patent Trial and Appeal Board, 88 Fed. Reg. 24503Practices for America Invents Act Trial Proceedings Before the Patent Trial and Appeal Board, 88 Fed. Reg. 24503
, 24510 (Apr. 21, 2023) [hereinafter ANPRM].  (Apr. 21, 2023) [hereinafter ANPRM]. 
349 This section does not comprehensively review all of the proposed changes in the PREVAIL Act and
349 This section does not comprehensively review all of the proposed changes in the PREVAIL Act and
 ANPRM  proposed rulemaking notices. For . For 
example, this section does not analyze PREVAIL Act’s provisions on real parties-in-interest or USPTO fee diversion. example, this section does not analyze PREVAIL Act’s provisions on real parties-in-interest or USPTO fee diversion. 
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that it prohibited director review.350 Days after the Court decided 
that it prohibited director review.350 Days after the Court decided 
Arthrex, USPTO implemented , USPTO implemented 
the decision by establishing an “Interim Director Review Process” the decision by establishing an “Interim Director Review Process” 
(the Review Process) that that 
allows parties to seek director review of PTAB decisions.351 Although the allows parties to seek director review of PTAB decisions.351 Although the 
Arthrex decision  decision 
concerned only IPR,352 the concerned only IPR,352 the 
Interim Director Review Process applies to PGR and derivation proceedings as well.353  Review Process applies to PGR and derivation proceedings as well.353  
In July 2022, USPTO issued a Request for Comments on director review, stating it was soliciting public input to inform potential revisions to the Review Process and USPTO’s plan “to formalize those processes through notice-and-comment rulemaking.”354 As of March 2024, USPTO had not yet commenced notice-and-comment rulemaking to formalize the Review Process. USPTO has nonetheless continued to revise the Review Process since the request for comments.355  
As currently designed, theAs currently designed, the Interim Director Review Process allows parties to request director review of PTAB’s  Review Process allows parties to request director review of PTAB’s 
(1) institution decisions, (2) final written decisions, and (3) decisions granting requests for (1) institution decisions, (2) final written decisions, and (3) decisions granting requests for 
rehearing.rehearing.
356354 Requests for director review are limited to decisions that present either an abuse of  Requests for director review are limited to decisions that present either an abuse of 
discretion or “important issues of law or policy,” except that requests for review of final written discretion or “important issues of law or policy,” except that requests for review of final written 
decisions may also seek review of allegedly erroneous findings of material fact or legal decisions may also seek review of allegedly erroneous findings of material fact or legal 
conclusions.conclusions.
357355 Requests for director review may not include new evidence or arguments not  Requests for director review may not include new evidence or arguments not 
already in the record.already in the record.
358356 A body called the Advisory Committee, comprising at least 11 members  A body called the Advisory Committee, comprising at least 11 members 
from various USPTO business units, reviews requests for director review and makes from various USPTO business units, reviews requests for director review and makes 
recommendations on whether or not the Director should grant review.recommendations on whether or not the Director should grant review.
359357  
If the Director grants review, she generally makes a decision based on the existing record but may 
If the Director grants review, she generally makes a decision based on the existing record but may 
order additional briefing, discovery, or oral argument.order additional briefing, discovery, or oral argument.
360358 The Director reviews PTAB decisions  The Director reviews PTAB decisions 
de 
novo (i.e., without giving any deference to PTAB), except for decisions whether to institute a trial  (i.e., without giving any deference to PTAB), except for decisions whether to institute a trial 
or grant rehearing that do not involve important issues of law and policy, which are reviewed only or grant rehearing that do not involve important issues of law and policy, which are reviewed only 
for abuse of discretion.for abuse of discretion.
361359  
In addition to reviews requested by a party, the Director has authority to review PTAB decisions 
In addition to reviews requested by a party, the Director has authority to review PTAB decisions 
sua sponte (i.e., of her own volition). (i.e., of her own volition).
362360 Whereas parties may request review only of certain kinds Whereas parties may request review only of certain kinds
 of decisions, the Director may review any PTAB decision sua sponte.361 The Director may seek recommendations from the Advisory Committee whether or not to review a decision sua sponte.362 The Director may—but is not required to—give the parties an opportunity to submit briefing on sua sponte reviews.363  
 
 
350 
350 
Arthrex, 594 U.S. at 25 (“We conclude that a tailored approach is the appropriate one: Section 6(c) cannot , 594 U.S. at 25 (“We conclude that a tailored approach is the appropriate one: Section 6(c) cannot 
constitutionally be enforced to the extent that its requirements prevent the Director from reviewing final decisions constitutionally be enforced to the extent that its requirements prevent the Director from reviewing final decisions 
rendered by APJs.”). rendered by APJs.”). 
351 
351 
See USPTO, Revised Interim Director Review Process, https://www.uspto.gov/patents/ptab/decisions/revised- USPTO, Revised Interim Director Review Process, https://www.uspto.gov/patents/ptab/decisions/revised-
interim-director-review-process (last visited Mar. 28, 2024) [hereinafter interim-director-review-process (last visited Mar. 28, 2024) [hereinafter 
Interim Director Review Process]; Request for Comments on Review Process]; Request for Comments on 
Director Review, Precedential Opinion Panel Review, and Internal Circulation and Review of Patent Trial and Appeal Director Review, Precedential Opinion Panel Review, and Internal Circulation and Review of Patent Trial and Appeal 
Board Decisions, 87 Fed. Reg. 43249 (July 20, 2022) [hereinafter Request for Comments on Director Review] (“On Board Decisions, 87 Fed. Reg. 43249 (July 20, 2022) [hereinafter Request for Comments on Director Review] (“On 
June 29, 2021, the USPTO implemented an interim process for Director review.”). June 29, 2021, the USPTO implemented an interim process for Director review.”). 
352 352 
Arthrex, 594 U.S. at 26 (“[T]his suit concerns only the Director's ability to supervise APJs in adjudicating petitions , 594 U.S. at 26 (“[T]his suit concerns only the Director's ability to supervise APJs in adjudicating petitions 
for inter partes review. We do not address the Director’s supervision over other types of adjudications conducted by the for inter partes review. We do not address the Director’s supervision over other types of adjudications conducted by the 
PTAB.”). PTAB.”). 
353 
353 
See  Interim Director Review Process, Review Process, 
supra  notenote 351, Section 1. 354 See id., Section 2.A. 355 See id., Section 2.B. 356 See id., Section 3.E. 357 See id., Section 4.A. 358 See id., Section 4.A.ii. 359 See id., Section 5.C. 360 See id., Section 4.C. 361 See id., Section 2.A. 362 See id., Section 4.A. 363 See id., 351, Section 1. 354 Request for Comments on Director Review, supra note 351, at 43249.  355 See Request for Comments on Director Review, supra note 351, at 43250–51 (noting various updates in 2022); Review Process, supra note 351 (noting September 2023 changes and noting USPTO “continues to clarify and update the interim process”).  
356 See Review Process, supra note 351, Section 2.A. 357 See id., Section 2.B. 358 See id., Section 3.E. 359 See id., Section 4.A. 360 See id., Section 4.A.ii. 361 See id., Section 5.C. 362 See id., Section 4.C. 
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of decisions, the Director may review any PTAB decision sua sponte.363 The Director may seek recommendations from the Advisory Committee whether or not to review a decision sua sponte.364 The Director may—but is not required to—give the parties an opportunity to submit briefing on sua sponte reviews.365 Section 4.C. 
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If the Director decides to review a PTAB decision, either upon request of a party or sua sponte, 
If the Director decides to review a PTAB decision, either upon request of a party or sua sponte, 
she may choose to delegate the review to a Delegated Rehearing Panel (DRP).she may choose to delegate the review to a Delegated Rehearing Panel (DRP).
366364 A DRP is  A DRP is 
composed of APJs who did not serve on the initial panel.composed of APJs who did not serve on the initial panel.
367365 Whether or not the Director delegates  Whether or not the Director delegates 
review to a DRP, the review to a DRP, the 
review process concludes with a decision that affirms, reverses, modifies, or process concludes with a decision that affirms, reverses, modifies, or 
vacates the PTAB’s decision; remands the decision for further PTAB proceedings; or some vacates the PTAB’s decision; remands the decision for further PTAB proceedings; or some 
combination of the above. Review decisions constitute final written decisions that may be combination of the above. Review decisions constitute final written decisions that may be 
appealed to the Federal Circuit,appealed to the Federal Circuit,
368366 and a party may also request rehearing of a review decision. and a party may also request rehearing of a review decision.
369 
Concerns Regarding Transparency and APJ Independence  
While the 367 
In April 2024, USPTO published a notice of proposed rulemaking (NPRM) that proposes to codify in USPTO regulations a director review process that generally “is consistent with the current interim process.”368 The proposed rule deviates from the current Interim Director Review Process in some respects, however. As commentators have noted,369 the proposed rule would not expressly limit the grounds to request director review, as the Interim Director Review Process does (i.e., limiting director review to decisions presenting an abuse of discretion, important issues of law or policy, and—for final written decisions only—erroneous findings of material fact or erroneous legal conclusions).370 The proposed rule would also require that, if the Director grants review and does not withdraw the grant, the review must conclude with “a decision or order that provides the reasons for the Director’s disposition of the case.”371 In addition, the proposed rule would prohibit communications from third parties from being considered in the review process, except for “authorized amicus briefing.”372 
Concerns Regarding Transparency and APJ Independence  
While the Interim Director Review Process governs director review of already-issued decisions, PTAB’s Review Process governs director review of already-issued decisions, PTAB’s 
management has utilized various other practices for oversight and peer review of draft decisions management has utilized various other practices for oversight and peer review of draft decisions 
before they are issued.before they are issued.
370373 Some stakeholders have raised concerns about the transparency of these  Some stakeholders have raised concerns about the transparency of these 
practices and their potential effects on the independence of APJs.practices and their potential effects on the independence of APJs.
371374    
In December 2022, the U.S. Government Accountability Office (GAO) issued a report making 
In December 2022, the U.S. Government Accountability Office (GAO) issued a report making 
recommendations that included “specifying in finalized policies PTAB management and USPTO recommendations that included “specifying in finalized policies PTAB management and USPTO 
Director roles in internal oversight processes and circumstances in which judges are required to Director roles in internal oversight processes and circumstances in which judges are required to 
incorporate management comments” in their decisions.incorporate management comments” in their decisions.
372375 GAO noted that some stakeholders and  GAO noted that some stakeholders and 
APJs were uncertain about the role of the Director and PTAB management in overseeing panel APJs were uncertain about the role of the Director and PTAB management in overseeing panel 
decisions.373 One area of uncertainty concerned whether panels were required to incorporate comments management provided on draft decisions.374  
The GAO report also explored to what extent, if at all, PTAB management might change or expand the composition of PTAB panels to influence case outcomes.375 Eighty percent of APJs surveyed by GAO reported experiencing panel changes, 20% of whom felt that such changes were made “to alter or influence” panel decisions.376 PTAB management reported that it was 
 
363 See id., Section 2.A. 364 See id., Section 4.A. 365 See id., Section 4.C. 366
 
364  See  id., Section 5.A.iii  Section 5.A.iii 
367365  See Delegated Rehearing Panel, Section 2.A (“The DRP shall be selected from the Chief Judge, Deputy Chief  Delegated Rehearing Panel, Section 2.A (“The DRP shall be selected from the Chief Judge, Deputy Chief 
Judge, Vice Chief Judges, and Senior Lead Judges, excluding judges who served on the original Board panel for the Judge, Vice Chief Judges, and Senior Lead Judges, excluding judges who served on the original Board panel for the 
case under review or otherwise have a conflict with the case.”). case under review or otherwise have a conflict with the case.”). 
368 See 366 See Interim Director Review Process, Review Process, 
supra  notenote 351, Section 5.C.i. Section 5.C.i. 
369367  See  id., Section 5.C.ii. , Section 5.C.ii. 
370 See generally GAO PTAB REPORT, supra note 102, at 14 (providing timeline of PTAB oversight mechanisms). 371 See id. at 41–42 (making recommendations to USPTO Director).  372 Id. at “Highlights” page. 373 Id. at 33. 374 Id. at 29–31. 375 Id. at 36. 376 Id. at 36. 
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“exceptionally rare to use paneling as a vehicle for oversight.”377 Overall, 75% of judges responded that oversight practices “had an effect on their independence.”378 
In October 2023, PTAB issued a standard operating procedure (SOP 4)379 to address some of the issues discussed in the GAO report.380 SOP 4 allows panel members to request nonbinding input on draft decisions from a pool of “non-management peer judges”381368 Director Review NPRM, supra note 348, at 26810. 369 See Kassandra M. Officer et al., USPTO Publishes Notice of Proposed Rulemaking for Director Review, FINNEGAN (April 2024), https://www.finnegan.com/en/insights/blogs/at-the-ptab-blog/uspto-publishes-notice-of-proposed-rulemaking-for-director-review.html. 
370 Compare Director Review NPRM, supra note 348, at 26813 with Interim Director Review Process, supra note 351, Section 2.B. 
371 Director Review NPRM, supra note 348, at 26813. 372 Id. 373 See generally GAO PTAB REPORT, supra note 102, at 14 (providing timeline of PTAB oversight mechanisms). 374 See id. at 41–42 (making recommendations to USPTO Director).  375 Id. at “Highlights” page. 
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decisions.376 One area of uncertainty concerned whether panels were required to incorporate comments management provided on draft decisions.377  
The GAO report also explored to what extent, if at all, PTAB management might change or expand the composition of PTAB panels to influence case outcomes.378 Eighty percent of APJs surveyed by GAO reported experiencing panel changes, 20% of whom felt that such changes were made “to alter or influence” panel decisions.379 PTAB management reported that it was “exceptionally rare to use paneling as a vehicle for oversight.”380 Overall, 75% of judges responded that oversight practices “had an effect on their independence.”381 
In October 2023, PTAB issued a standard operating procedure (SOP 4)382 to address some of the issues discussed in the GAO report.383 SOP 4 allows panel members to request nonbinding input on draft decisions from a pool of “non-management peer judges”384 and/or from a review team  and/or from a review team 
designated by PTAB Executive Management, which consists of the Chief Judge, Deputy Chief designated by PTAB Executive Management, which consists of the Chief Judge, Deputy Chief 
Judge, Vice Chief Judges, and Senior Lead Judges.Judge, Vice Chief Judges, and Senior Lead Judges.
382385 SOP 4 gives PTAB panel members  SOP 4 gives PTAB panel members 
discretion whether or not to solicit input from these bodies and gives PTAB panels “final discretion whether or not to solicit input from these bodies and gives PTAB panels “final 
authority and responsibility for the content of a decision,” including “in what manner, if at all, to authority and responsibility for the content of a decision,” including “in what manner, if at all, to 
incorporate any feedback.”incorporate any feedback.”
383386 SOP 4 gives a third body responsibility for reviewing issued  SOP 4 gives a third body responsibility for reviewing issued 
decisions to determine whether they require further attention, such as sua sponte Director decisions to determine whether they require further attention, such as sua sponte Director 
review.review.
384387  
SOP 4 states that the Director will not be involved in directing or influencing panel decisions 
SOP 4 states that the Director will not be involved in directing or influencing panel decisions 
before they issue (unless the Director is a member of the panel).before they issue (unless the Director is a member of the panel).
385388 SOP 4 also states that the  SOP 4 also states that the 
Director will not influence paneling decisions prior to issuance of a decision, but she may direct Director will not influence paneling decisions prior to issuance of a decision, but she may direct 
repaneling when reviewing or rehearing an issued decision.repaneling when reviewing or rehearing an issued decision.
386389  
The PREVAIL Act contains provisions that its sponsors contend would increase transparency of 
The PREVAIL Act contains provisions that its sponsors contend would increase transparency of 
PTAB proceedings.PTAB proceedings.
387390 It would require the Director to issue a separate written opinion in the  It would require the Director to issue a separate written opinion in the 
public record that sets forth the reasons for any reconsideration, rehearing, or review of an IPR or public record that sets forth the reasons for any reconsideration, rehearing, or review of an IPR or 
PGR decision.388 The bill’s sponsors state that this requirement would “increase transparency and reduce concerns that the Director unfairly influences PTAB decisions.”389 The bill would also require that any changes to the membership of a panel be noted in the public record.390 
The PREVAIL Act would also require the Director—and any other officers with disciplinary or supervisory authority over APJs—to “refrain from communications with [a PTAB panel] that direct or otherwise influence any merits decision.”391 Some commentators would like to see this provision go further by extending this prohibition on so-called “ex parte contacts” to institution 
 
377
 
376 Id. at 33. 377 Id. at 29–31. 378 Id. at 36. 379 Id. at 36. 380  Id. at 36 n. 78. at 36 n. 78. 
378381  Id. at 23. at 23. 
379382 PTAB, STANDARD OPERATING PROCEDURE 4: PROCEDURE FOR PRE-ISSUANCE OPTIONAL DECISION REVIEW AND POST- PTAB, STANDARD OPERATING PROCEDURE 4: PROCEDURE FOR PRE-ISSUANCE OPTIONAL DECISION REVIEW AND POST-
ISSUANCE DECISION REVIEW (Oct. 2023), https://www.uspto.gov/sites/default/files/documents/ptab_sop_4-2023-oct.pdf ISSUANCE DECISION REVIEW (Oct. 2023), https://www.uspto.gov/sites/default/files/documents/ptab_sop_4-2023-oct.pdf 
[hereinafter SOP 4]. [hereinafter SOP 4]. 
380383 In its report, GAO noted that some of these changes had previously been incorporated into the  In its report, GAO noted that some of these changes had previously been incorporated into the 
Interim Director Review Process as of Review Process as of 
May 2022. May 2022. 
See GAO PTAB REPORT,  GAO PTAB REPORT, 
supra notenote 102, at “Highlights” page. GAO stated that such changes could at “Highlights” page. GAO stated that such changes could 
improve transparency about oversight practices “if finalized and . . . made publicly available.” improve transparency about oversight practices “if finalized and . . . made publicly available.” 
Id.  .  
381384 SOP 4,  SOP 4, 
supra note note
 379382, at 1–2 (a Circulation Judge Pool or CPJ). at 1–2 (a Circulation Judge Pool or CPJ). 
382385  Id. at 3–4 (PTAB Management Pre-Issuance Optional Review team). at 3–4 (PTAB Management Pre-Issuance Optional Review team). 
383386  Id. at 1. at 1. 
384387  Id. at 5 (PTAB Post-Issuance Review team). at 5 (PTAB Post-Issuance Review team). 
385388  Id. at 4–5. at 4–5. 
386389  Id. at 5. at 5. 
387390 THE PREVAIL ACT WILL HELP ENSURE U.S. GLOBAL TECHNOLOGY LEADERSHIP AND PROTECT ECONOMIC AND  THE PREVAIL ACT WILL HELP ENSURE U.S. GLOBAL TECHNOLOGY LEADERSHIP AND PROTECT ECONOMIC AND 
NATIONAL SECURITY 2, https://www.coons.senate.gov/imo/media/doc/prevail_act_fact_sheet.pdf (last visited Mar. 28, NATIONAL SECURITY 2, https://www.coons.senate.gov/imo/media/doc/prevail_act_fact_sheet.pdf (last visited Mar. 28, 
2024) [hereinafter PREVAIL ACT FACT SHEET].  2024) [hereinafter PREVAIL ACT FACT SHEET].  
388 PREVAIL Act, S. 2220, 118th Cong. § 4(f), 5(f) (2023). 389 PREVAIL ACT FACT SHEET, supra note 387, at 2. 390 S. 2220 § 3. 391 S. 2220 § 3. 
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PGR decision.391 The bill’s sponsors state that this requirement would “increase transparency and reduce concerns that the Director unfairly influences PTAB decisions.”392 The bill would also require that any changes to the membership of a panel be noted in the public record.393 
The PREVAIL Act would also require the Director—and any other officers with disciplinary or supervisory authority over APJs—to “refrain from communications with [a PTAB panel] that direct or otherwise influence any merits decision.”394 Some commentators would like to see this provision go further by extending this prohibition on so-called “ex parte contacts” to institution and procedural decisions.395 Some have also called on Congress to restore APJs’ pre- Some have also called on Congress to restore APJs’ pre-
Arthrex  independence by requiring that they be appointed by the President and confirmed by the Senate, independence by requiring that they be appointed by the President and confirmed by the Senate, 
thus making them superior officers who may constitutionally be insulated from Director thus making them superior officers who may constitutionally be insulated from Director 
supervision.supervision.
393396  
Who Has Standing to Petition PTAB and Appeal Its Decisions? 
Although many IPRs are brought by persons sued for patent infringement in court, being sued or Although many IPRs are brought by persons sued for patent infringement in court, being sued or 
threatened with suit is not a requirement to bring an IPR or PGR petition. Under the AIA, any threatened with suit is not a requirement to bring an IPR or PGR petition. Under the AIA, any 
person other than the patent holder may file an IPR or PGR petition.person other than the patent holder may file an IPR or PGR petition.
394397 By contrast, parties may  By contrast, parties may 
challenge patents in federal court only if there is “a substantial controversy, between the parties challenge patents in federal court only if there is “a substantial controversy, between the parties 
having adverse legal interests, of sufficient immediacy and reality.”having adverse legal interests, of sufficient immediacy and reality.”
395398  
The lack of a standing requirement means that a broader set of people and groups may use IPR 
The lack of a standing requirement means that a broader set of people and groups may use IPR 
and PGR, even if they do not make products that could infringe the challenged patents. For and PGR, even if they do not make products that could infringe the challenged patents. For 
example, public interest and nonprofit groups, such as the Electronic Frontier example, public interest and nonprofit groups, such as the Electronic Frontier 
Foundation396Foundation399 and  and 
Consumer Watchdog,Consumer Watchdog,
397400 have used IPRs to challenge patents. In addition, some IPRs are brought  have used IPRs to challenge patents. In addition, some IPRs are brought 
by petitioning organizations that receive funding from companies that may be sued for patent by petitioning organizations that receive funding from companies that may be sued for patent 
infringement. For example, Unified Patents—an organization whose members include many large infringement. For example, Unified Patents—an organization whose members include many large 
technology technology 
companies398companies401—is among the most frequent users of IPR.—is among the most frequent users of IPR.
399 
The PREVAIL Act would restrict who may file petitions for IPR (but not for PGR).400 The bill’s language would allow a person to file an IPR petition only if they have been sued for infringing the patent or “charged with infringement” of the patent.401 The latter term is defined to mean a “real and substantial controversy” of the sort required for standing in federal court.402  
Supporters of this standing requirement contend it would encourage independent and small business inventors to develop and seek patent protection for new inventions by giving them assurance that the patents would not be challenged unless they assert them against alleged infringers.403 Opponents argue that restricting standing in this manner would stop petitioning 
 
392402 
 
391 PREVAIL Act, S. 2220, 118th Cong. § 4(f), 5(f) (2023). 392 PREVAIL ACT FACT SHEET, supra note 390, at 2. 393 S. 2220 § 3. 394 S. 2220 § 3. 395 See Written Statement of Joseph Matal,Written Statement of Joseph Matal,
 Reforming the Patent Trial and Appeal Board—The PREVAIL Act and 
Proposals to Promote U.S. Innovation Leadership: Hearing Before the Senate Comm. on the Judiciary, Subcomm. on 
Intellectual Property, 118th Cong. (Nov. 8, 2023), https://www.judiciary.senate.gov/download/2023-11-08-testimony-, 118th Cong. (Nov. 8, 2023), https://www.judiciary.senate.gov/download/2023-11-08-testimony-
matal, at 17 [hereinafter Matal Statement]. matal, at 17 [hereinafter Matal Statement]. 
393396  See id. at 18.  at 18. 
394397 35 U.S.C. §§ 311(a), 321(a).  35 U.S.C. §§ 311(a), 321(a). 
395398 Prasco LLC v. Medicis Pharm. Corp., 537 F.3d 1329, 1334 (Fed. Cir. 2008) (quoting MedImmune, Inc. v.  Prasco LLC v. Medicis Pharm. Corp., 537 F.3d 1329, 1334 (Fed. Cir. 2008) (quoting MedImmune, Inc. v. 
Genentech, Inc., 549 U.S. 118, 127 (2007)). Genentech, Inc., 549 U.S. 118, 127 (2007)). 
396399  See Pers. Audio, LLC v. Elec. Frontier Found., 867 F.3d 1246 (Fed. Cir. 2017) (appeal from IPR brought by the Pers. Audio, LLC v. Elec. Frontier Found., 867 F.3d 1246 (Fed. Cir. 2017) (appeal from IPR brought by the 
Electronic Frontier Foundation). Electronic Frontier Foundation). 
397400  See Consumer Watchdog v. Wis. Alumni Rsch. Found., 753 F.3d 1258 (Fed. Cir. 2014) (appeal from IPR brought  Consumer Watchdog v. Wis. Alumni Rsch. Found., 753 F.3d 1258 (Fed. Cir. 2014) (appeal from IPR brought 
by Consumer Watchdog). by Consumer Watchdog). 
398401  See UNIFIED PATENTS,  UNIFIED PATENTS, 
Members, https://www.unifiedpatents.com/members (last visited Mar. 28, 2024). , https://www.unifiedpatents.com/members (last visited Mar. 28, 2024). 
399402  See UNIFIED PATENTS, UNIFIED PATENTS,
 2022 Annual PTAB Report, https://portal.unifiedpatents.com/ptab/annual-report (last visited , https://portal.unifiedpatents.com/ptab/annual-report (last visited 
Mar. 28, 2024) (listing Unified Patents as the sixth most active PTAB petitioner in 2022, behind Apple, Inc., Samsung Mar. 28, 2024) (listing Unified Patents as the sixth most active PTAB petitioner in 2022, behind Apple, Inc., Samsung 
Electronics Co., Google LLC, Samsung Electronics America, and Amazon.com). Electronics Co., Google LLC, Samsung Electronics America, and Amazon.com). 
400 S. 2220, 118th Cong. § 4(a). 401 Id. 
402 Id.; see generally MedImmune, 549 U.S. at 126–36. 403 See Written Statement of Michelle E. Armond, Reforming the Patent Trial and Appeal Board—The PREVAIL Act 
and Proposals to Promote U.S. Innovation Leadership: Hearing Before the Senate Comm. on the Judiciary, Subcomm. 
(continued...) 
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The PREVAIL Act would restrict who may file petitions for IPR (but not for PGR).403 The bill’s language would allow a person to file an IPR petition only if they have been sued for infringing the patent or “charged with infringement” of the patent.404 The latter term is defined to mean a “real and substantial controversy” of the sort required for standing in federal court.405  
Supporters of this standing requirement contend it would encourage independent and small business inventors to develop and seek patent protection for new inventions by giving them assurance that the patents would not be challenged unless they assert them against alleged infringers.406 Opponents argue that restricting standing in this manner would stop petitioning organizations and others from filing petitions against low-quality patents used by “nuisance-organizations and others from filing petitions against low-quality patents used by “nuisance-
settlement plaintiffs” that file abusive patent infringement lawsuits against parties who cannot, settlement plaintiffs” that file abusive patent infringement lawsuits against parties who cannot, 
individually, afford to litigate such lawsuits.individually, afford to litigate such lawsuits.
404407 Opponents also argue that restrictions on standing  Opponents also argue that restrictions on standing 
could reduce consumer choices and raise prices by preventing businesses from filing “clearance could reduce consumer choices and raise prices by preventing businesses from filing “clearance 
petitions” to gain assurance that they can commercialize products without risking patent petitions” to gain assurance that they can commercialize products without risking patent 
infringement.infringement.
405408    
What Should Be PTAB’s Standards for Invalidation and Claim 
Construction? 
Invalidity: Preponderance of Evidence or Clear and Convincing Evidence? 
One difference between district court litigation and IPRs and PGRs is the standard of proof 
One difference between district court litigation and IPRs and PGRs is the standard of proof 
needed to invalidate a patent. The Patent Act provides that patents are presumed to be valid.needed to invalidate a patent. The Patent Act provides that patents are presumed to be valid.
406409  Based on that presumption, the Supreme Court and the Federal Circuit have held that district Based on that presumption, the Supreme Court and the Federal Circuit have held that district 
courts may invalidate a patent only if there is “clear and convincing evidence” of invalidity.courts may invalidate a patent only if there is “clear and convincing evidence” of invalidity.
407410  The AIA, on the other hand, allows IPR and PGR petitioners to show that a patent is invalid by a The AIA, on the other hand, allows IPR and PGR petitioners to show that a patent is invalid by a 
lower standard: the “preponderance of the evidence.”lower standard: the “preponderance of the evidence.”
408411  
The sponsors of the PREVAIL Act propose to “harmonize” these standards by holding PTAB 
The sponsors of the PREVAIL Act propose to “harmonize” these standards by holding PTAB 
challengers to the higher, “clear and convincing evidence” standard used in district court.challengers to the higher, “clear and convincing evidence” standard used in district court.
409412 Thus,  Thus, 
the PREVAIL Act would place the burden on the petitioner in an IPR or PGR to prove the the PREVAIL Act would place the burden on the petitioner in an IPR or PGR to prove the 
unpatentability of a previously issued claim of a patent by clear and convincing evidence.unpatentability of a previously issued claim of a patent by clear and convincing evidence.
410 (With respect to substitute claims proposed by the patentee during an IPR or PGR, however, the petitioner would have only “the burden of persuasion, by a preponderance of the evidence,” to show unpatentability.411)  
Proponents of this change contend that it would “promote consistency by harmonizing standards between the PTAB and district court.”412 Opponents argue that, while it is appropriate for district courts to give “deference to the expert agency [USPTO] that issued the patent” by using the clear-and-convincing-evidence standard to invalidate a patent, USPTO should not be required to defer to its own earlier decision to grant a patent, and therefore PTAB should continue to use the lower preponderance-of-evidence standard in AIA proceedings.413 
 
413 
 
403 S. 2220, 118th Cong. § 4(a). 404 Id. 405 Id.; see generally MedImmune, 549 U.S. at 126–36. 406 See Written Statement of Michelle E. Armond, Reforming the Patent Trial and Appeal Board—The PREVAIL Act and Proposals to Promote U.S. Innovation Leadership: Hearing Before the Senate Comm. on the Judiciary, Subcomm. on Intellectual Property, 118th Cong. (Nov. 8, 2023), https://www.judiciary.senate.gov/download/2023-11-08-, 118th Cong. (Nov. 8, 2023), https://www.judiciary.senate.gov/download/2023-11-08-
testimony-armond, at 12 [hereinafter Armond Statement]. testimony-armond, at 12 [hereinafter Armond Statement]. 
404407  See Matal Statement,  Matal Statement, 
supra  note 392note 395, at 12–14. at 12–14. 
405408  See id. at 11–12 (arguing many clearance petitions are directed against patents owned by NPEs).  at 11–12 (arguing many clearance petitions are directed against patents owned by NPEs). 
406409 35 U.S.C. § 282 (“A patent shall be presumed valid.”).  35 U.S.C. § 282 (“A patent shall be presumed valid.”). 
407410 Microsoft Corp. v. i4iLP, 564 U.S. 91, 95 (2011). The Supreme Court noted in its opinion that the Federal Circuit— Microsoft Corp. v. i4iLP, 564 U.S. 91, 95 (2011). The Supreme Court noted in its opinion that the Federal Circuit—
the appellate court with jurisdiction over patent litigation—had required the same “clear and convincing evidence” the appellate court with jurisdiction over patent litigation—had required the same “clear and convincing evidence” 
standard since 1984. standard since 1984. 
See id. at 97 (“In the nearly 30 years since  at 97 (“In the nearly 30 years since 
American Hoist, the Federal Circuit has never wavered , the Federal Circuit has never wavered 
in this interpretation of § 282.” (citing Am. Hoist & Derrick Co. v. Sowa & Sons, Inc., 725 F.2d 1350 (Fed. Cir. in this interpretation of § 282.” (citing Am. Hoist & Derrick Co. v. Sowa & Sons, Inc., 725 F.2d 1350 (Fed. Cir. 
1984))). 1984))). 
408411 35 U.S.C. § 316(e).  35 U.S.C. § 316(e). 
409412 PREVAIL ACT PREVAIL ACT
 FACT SHEET, FACT SHEET, 
supra  note 387note 390, at 2. at 2. 
410413 S. 2220, 118th Cong. §§ 4(d)(2), 5(d)(2).  S. 2220, 118th Cong. §§ 4(d)(2), 5(d)(2). 
411 S. 2220, 118th Cong. §§ 4(d)(2), 5(d)(2). 412 Armond Statement, supra note 403, at 11. 413 Matal Statement, supra note 392, at 9. 
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(With respect to substitute claims proposed by the patentee during an IPR or PGR, however, the petitioner would have only “the burden of persuasion, by a preponderance of the evidence,” to show unpatentability.414)  
Proponents of this change contend that it would “promote consistency by harmonizing standards between the PTAB and district court.”415 Opponents argue that, while it is appropriate for district courts to give “deference to the expert agency [USPTO] that issued the patent” by using the clear-and-convincing-evidence standard to invalidate a patent, USPTO should not be required to defer to its own earlier decision to grant a patent, and therefore PTAB should continue to use the lower preponderance-of-evidence standard in AIA proceedings.416 
Claim Construction: Should USPTO or Congress Decide the Right Standard? 
PTAB previously used a different standard than district courts for the construction (i.e., 
PTAB previously used a different standard than district courts for the construction (i.e., 
interpretation) of patent claims. Before 2018, PTAB gave claims their “broadest reasonable interpretation) of patent claims. Before 2018, PTAB gave claims their “broadest reasonable 
construction” (BRC),construction” (BRC),
414417 the standard used by USPTO during patent prosecution. the standard used by USPTO during patent prosecution.
415418    
District courts and the ITC, by contrast, construe claims according to a standard articulated by the 
District courts and the ITC, by contrast, construe claims according to a standard articulated by the 
Federal Circuit in its 2005 opinion in Federal Circuit in its 2005 opinion in 
Phillips v. AWH Corp..
416419 The  The 
Phillips standard requires the standard requires the 
adjudicator to construe claim terms according to their “ordinary and customary meaning . . . to a adjudicator to construe claim terms according to their “ordinary and customary meaning . . . to a 
person of ordinary skill in the art in question at the time of the invention.”person of ordinary skill in the art in question at the time of the invention.”
417420 To discern this  To discern this 
meaning, courts must look to the claim themselves, the patent specification, documents from the meaning, courts must look to the claim themselves, the patent specification, documents from the 
prosecution of the patent (prosecution history), and, to a lesser degree, “extrinsic evidence” such prosecution of the patent (prosecution history), and, to a lesser degree, “extrinsic evidence” such 
as expert testimony, dictionaries, and treatises.as expert testimony, dictionaries, and treatises.
418421 Construing claims under the  Construing claims under the 
Phillips standard standard 
tends to result in a narrower scope of patent claims than the BRC standard, potentially making it tends to result in a narrower scope of patent claims than the BRC standard, potentially making it 
harder for patentees to prove patent infringement (since fewer accused articles may fall within the harder for patentees to prove patent infringement (since fewer accused articles may fall within the 
claims) but easier to defend patent validity (since less prior art may anticipate the claims or render claims) but easier to defend patent validity (since less prior art may anticipate the claims or render 
them obvious).  them obvious).  
In 2018, USPTO issued a final rule requiring PTAB to use the 
In 2018, USPTO issued a final rule requiring PTAB to use the 
Phillips standard instead of the  standard instead of the 
BRC standard to construe patent claims in AIA proceedings.BRC standard to construe patent claims in AIA proceedings.
419422 Thus, PTAB now applies the same  Thus, PTAB now applies the same 
claim construction standard used in district courts and the ITC. USPTO noted that the majority of claim construction standard used in district courts and the ITC. USPTO noted that the majority of 
comments it received supported this change.comments it received supported this change.
420 UPSTO423 USPTO cited the benefits of “greater uniformity  cited the benefits of “greater uniformity 
and predictability” and “judicial efficiency” as reasons for PTAB to use the same claim and predictability” and “judicial efficiency” as reasons for PTAB to use the same claim 
construction standard as districts courts and the ITC, especially since many patents subject to AIA construction standard as districts courts and the ITC, especially since many patents subject to AIA 
proceedings are also involved in litigation in those forums.proceedings are also involved in litigation in those forums.
421 UPSTO424 USPTO also noted that the rule 
 
414 S. 2220, 118th Cong. §§ 4(d)(2), 5(d)(2). 415 Armond Statement, supra note 406, at 11. 416 Matal Statement, supra note 395, at 9. 417 also noted that the rule addresses “potential unfairness” that some patent owners believed could result from PTAB construing claim terms more broadly than other forums.422 PTAB’s use of the Phillips standard does not necessarily mean PTAB, district courts, and the ITC reach identical constructions of specific claims or claim terms, although the 2018 rule requires PTAB to “consider” prior district court or ITC constructions that are “timely made of record” in AIA proceedings.423 
The PREVAIL Act essentially seeks to codify the 2018 rule change so that PTAB would be statutorily required to continue using the Phillips standard.424 Currently, as the Supreme Court held in Cuozzo, the AIA “leaves open the question of which claim construction standard is 
 
414 Cuozzo Speed Techs., LLC v. Lee, 579 U.S. 261, 270 (2016) (citing 37 C.F.R. § 42.100(b)).  Cuozzo Speed Techs., LLC v. Lee, 579 U.S. 261, 270 (2016) (citing 37 C.F.R. § 42.100(b)). 
415418 Phillips v. AWH Corp., 415 F.3d 1303, 1316 (Fed. Cir. 2005) (en banc) (“The Patent and Trademark Office . . .  Phillips v. AWH Corp., 415 F.3d 1303, 1316 (Fed. Cir. 2005) (en banc) (“The Patent and Trademark Office . . . 
determines the scope of claims in patent applications not solely on the basis of the claim language, but upon giving determines the scope of claims in patent applications not solely on the basis of the claim language, but upon giving 
claims their broadest reasonable construction ‘in light of the specification as it would be interpreted by one of ordinary claims their broadest reasonable construction ‘in light of the specification as it would be interpreted by one of ordinary 
skill in the art.’” (quoting In re Am. Acad. of Sci. Tech. Ctr., 367 F.3d 1359, 1364 (Fed. Cir. 2004))). skill in the art.’” (quoting In re Am. Acad. of Sci. Tech. Ctr., 367 F.3d 1359, 1364 (Fed. Cir. 2004))). 
416419  See id. . 
417420  Id. at 1313.  at 1313. 
418421  See id. at 1313–19.  at 1313–19. 
419422  See Changes to the Claim Construction Standard for Interpreting Claims in Trial Proceedings Before the Patent Trial Changes to the Claim Construction Standard for Interpreting Claims in Trial Proceedings Before the Patent Trial 
and Appeal Board, 83 Fed. Reg. 51340 (Oct. 11, 2018) (codified at 37 C.F.R. § 42.100(b)). and Appeal Board, 83 Fed. Reg. 51340 (Oct. 11, 2018) (codified at 37 C.F.R. § 42.100(b)). 
420423  See id. at 51345.  at 51345. 
421424 Id. at 51342. 
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addresses “potential unfairness” that some patent owners believed could result from PTAB construing claim terms more broadly than other forums.425 PTAB’s use of the Phillips standard does not necessarily mean PTAB, district courts, and the ITC reach identical constructions of specific claims or claim terms, although the 2018 rule requires PTAB to “consider” prior district court or ITC constructions that are “timely made of record” in AIA proceedings.426 
The PREVAIL Act essentially seeks to codify the 2018 rule change so that PTAB would be statutorily required to continue using the Phillips standard.427 Currently, as the Supreme Court held in Cuozzo, the AIA “leaves open the question of which claim construction standard is  Id. at 51342. 422 See id. (“Because the [BRC] standard potentially reads on a broader universe of prior art than does the Phillips standard, a patent claim could potentially be found unpatentable in an AIA proceeding on account of [a broader] claim scope that the patent owner would not be able to assert in an infringement proceeding.”). 423 Id. at 51358–59 (codified at 37 C.F.R. §§ 42.100(b), .200(b)). 424 See S. 2220, 118th Cong. § 4(d)(3), 5(d)(3). 
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proper” and gives USPTO authority to select the proper standard through rulemaking.proper” and gives USPTO authority to select the proper standard through rulemaking.
425428 USPTO  USPTO 
exercised this authority when it initially adopted the BRC standard and, later, when it switched to exercised this authority when it initially adopted the BRC standard and, later, when it switched to 
the the 
Phillips standard. The PREVAIL Act would remove this authority from USPTO and prevent it  standard. The PREVAIL Act would remove this authority from USPTO and prevent it 
from reverting to the BRC standard or adopting any other alternative claim construction standard from reverting to the BRC standard or adopting any other alternative claim construction standard 
for PTAB. for PTAB. 
When Should PTAB Deny Institution of an IPR? 
As noted above, the AIA gives PTAB discretion to deny institution of an IPR. Questions about As noted above, the AIA gives PTAB discretion to deny institution of an IPR. Questions about 
when and how PTAB should exercise this discretion often arise in situations where a single patent when and how PTAB should exercise this discretion often arise in situations where a single patent 
is challenged multiple times or in multiple forums, including the following: is challenged multiple times or in multiple forums, including the following: 
•  
•  
Previously Addressed Prior Art and Arguments. An IPR raises the same  An IPR raises the same 
arguments or prior prior 
art
art
 or arguments already considered by PTAB in an earlier petition or during initial  already considered by PTAB in an earlier petition or during initial 
examination. examination. 
•  
•  
Parallel Petitions. A party files multiple IPRs against the same patent at  A party files multiple IPRs against the same patent at 
the 
or about 
the same time (e.g., based on different legal arguments or prior art). same time (e.g., based on different legal arguments or prior art). 
•  
•  
Serial Petitions. A party files subsequent IPRs against the same patent claims  A party files subsequent IPRs against the same patent claims 
following an initial petition by the same party challenging those claims. 
following an initial petition by the same party challenging those claims. 
•  
•  
Parallel District Court Litigation. A party files an IPR against patent claims  A party files an IPR against patent claims 
that are the subject of ongoing district court litigation. 
that are the subject of ongoing district court litigation. 
•  
•  
Patents Already Adjudicated in Court. A party files an IPR challenging the A party files an IPR challenging the 
validity of a patent that has already been litigated and upheld as valid in court.  
validity of a patent that has already been litigated and upheld as valid in court.  
This section discusses how PTAB currently approaches each of these scenarios and how 
This section discusses how PTAB currently approaches each of these scenarios and how 
both USPTO and some some Members of Congress Members of Congress 
and USPTO have proposed to reform PTAB’s practice in this area. As explained below, the PREVAIL Act would change PTAB’s practices in the above-listed scenarios in various ways. In addition, in April 2024, USPTO published a Notice of Proposed Rulemaking (NPRM) that would affect PTAB’s discretionary denial practice in three of these scenarios—previously addressed prior art and arguments, parallel petitions, and serial petitions—as detailed below.429 In 2023, USPTO had published an Advance Notice of Proposed Rulemaking (ANPRM) 
 
425 See id. (“Because the [BRC] standard potentially reads on a broader universe of prior art than does the Phillips standard, a patent claim could potentially be found unpatentable in an AIA proceeding on account of [a broader] claim scope that the patent owner would not be able to assert in an infringement proceeding.”). 
426 Id. at 51358–59 (codified at 37 C.F.R. §§ 42.100(b), .200(b)). 427 See S. 2220, 118th Cong. § 4(d)(3), 5(d)(3). 428 Cuozzo, 579 U.S. at 279–80. 429 See Discretionary Denial NPRM, supra note 348, at 28704–05. In addition, this NPRM would allow parties to file separate briefing on discretionary denial issues. See id. at 28704 (allowing petitioner and patent owner to file papers regarding whether there is good cause to institute parallel petitions), 28703–04 (allowing patent owner to file request (continued...) 
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that would also have changed PTAB’s practices regarding parallel district court litigation and patents already adjudicated in district court.430 The April 2024 NPRM on discretionary denial issues did not include proposed rules on those two scenarios but noted that USPTO “continues to consider issuing proposed rules” on issues raised in the ANPRM.431  have proposed to reform PTAB’s practice in this area. 
Petitions Raising Previously Presented Prior Art and Arguments 
As noted above, when PTAB decides whether or not to institute an IPR, 35 U.S.C. § 325(d) 
As noted above, when PTAB decides whether or not to institute an IPR, 35 U.S.C. § 325(d) 
authorizes USPTO to consider whether “substantially the same prior art or arguments” were authorizes USPTO to consider whether “substantially the same prior art or arguments” were 
“previously presented” to USPTO.“previously presented” to USPTO.
426432 This may occur when an IPR petition raises prior art or  This may occur when an IPR petition raises prior art or 
arguments that USPTO considered during its initial examination (i.e., prosecution) of the patent, arguments that USPTO considered during its initial examination (i.e., prosecution) of the patent, 
earlier AIA proceedings (i.e., earlier IPRs or PGRs), or other USPTO proceedings.earlier AIA proceedings (i.e., earlier IPRs or PGRs), or other USPTO proceedings.
427433  
PTAB currently applies a two-part test to decide whether to deny institution under 
PTAB currently applies a two-part test to decide whether to deny institution under 
Section 325(d).Section 325(d).
428434 PTAB considers first whether “the same or substantially the same” prior art or  PTAB considers first whether “the same or substantially the same” prior art or 
arguments were previously presented to USPTO.arguments were previously presented to USPTO.
429435 If so, PTAB then considers “whether the  If so, PTAB then considers “whether the 
petitioner has demonstrated that the Office erred in a manner material to the patentability of petitioner has demonstrated that the Office erred in a manner material to the patentability of 
challenged claims.”challenged claims.”
430 
 
425 Cuozzo, 579 U.S. at 279–80. 426 35 U.S.C. § 325(d).  427 See ANPRM, supra note 348, at 24512 (noting such other proceedings including reissue, ex parte reexamination, and inter partes reexamination). 
428 See Advanced Bionics, LLC v. Med-El Elektromedizinische Geräte GmbH, IPR2019–01469, Paper 6 at 8 (P.T.A.B. Feb. 13, 2020) (precedential); ANPRM, supra note 348, at 24511. 
429 See ANPRM, supra note 348, at 24511. 430 Id. at 24511 (citing Advanced Bionics). 
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436 
In applying the first part of the test, PTAB may consider “similarities and material differences 
In applying the first part of the test, PTAB may consider “similarities and material differences 
between the asserted art and the prior art involved during examination,” “the cumulative nature of between the asserted art and the prior art involved during examination,” “the cumulative nature of 
the asserted art and the prior art evaluated during examination,” and “the extent of the overlap the asserted art and the prior art evaluated during examination,” and “the extent of the overlap 
between the arguments made during examination and the manner in which the petitioner relies on between the arguments made during examination and the manner in which the petitioner relies on 
the prior art or the patent owner distinguishes the prior art.”the prior art or the patent owner distinguishes the prior art.”
431  
437 For the second part of the test, PTAB may consider “the extent to which the asserted art was For the second part of the test, PTAB may consider “the extent to which the asserted art was 
evaluated during examination, including whether the prior art was the basis for rejection,” evaluated during examination, including whether the prior art was the basis for rejection,” 
“whether the petitioner has pointed out sufficiently how the examiner erred in its evaluation of “whether the petitioner has pointed out sufficiently how the examiner erred in its evaluation of 
the asserted prior art,” and “the extent to which additional evidence and facts presented in the the asserted prior art,” and “the extent to which additional evidence and facts presented in the 
petition warrant reconsideration of the prior art or arguments.”petition warrant reconsideration of the prior art or arguments.”
432 
In its ANPRM, USPTO proposes promulgating a new rule to replace the above test in the interest of “consistency, clarity, and efficiency.”433 Under the new rule, Section 325(d) would apply only where USPTO previously addressed the same or substantially similar prior art or arguments by “evaluat[ing] the art or arguments and articulat[ing] its consideration of the art or arguments in the record.”434 The proposal would also clarify438 
In its NPRM on discretionary denial issues, USPTO has proposed a rule that would limit Section 325(d) denials based on previously presented prior art to circumstances in which “the same or substantially the same prior art was previously meaningfully addressed” by USPTO with regard to the same or a related patent.439 The proposed rule provides that prior art is considered “substantially the  that prior art is considered “substantially the 
same” only if “the disclosure in the prior art previously addressed contains the same teaching relied upon in the petition and that teaching was addressed by the [PTO].”435 If Section 325(d) applies to a petition, then PTAB would deny institution unless the petitioner establishes “material error”—which would work similarly to the second part of the current test. Under the proposed rule, material error would not include cases where “reasonable minds can disagree,” but it would include errors of law—such as incorrect claim term constructions—and “overlooking specific teachings of the relevant prior art.”436 
The PREVAIL Act would impose a bright-line rule that PTAB must reject an IPR or PGR petition “that presents prior art or an argument that is the same or substantially the same as prior art or an argument that previously was presented to the [USPTO].”437 The sponsors contend that this requirement would prevent “costly and inefficient” proceedings involving the same prior art already considered by USPTO.438 Critics argue that this bill would require PTAB to deny institution of IPRs involving any prior art that was previously “presented” to USPTO, whether or not USPTO had actually considered that prior art—potentially incentivizing patent applicants to “immunize” their patents against future challenges by disclosing more prior art references than the examiner can “meaningfully consider.”439 
 
431same” only if “the disclosure in the prior art previously addressed contains the 
 
for discretionary denial on grounds other than parallel petitions, with an opportunity for petitioner and patent owner to file opposition to and reply in support of the request, respectively).  
430 See ANPRM, supra note 348, at 24510 (prior adjudications upholding validity), 24513–17 (parallel litigation).  431 Discretionary Denial NPRM, supra note 348, at 28695. 432 35 U.S.C. § 325(d).  433 See ANPRM, supra note 348, at 24512 (noting such other proceedings including reissue, ex parte reexamination, and inter partes reexamination). 
434 See Advanced Bionics, LLC v. Med-El Elektromedizinische Geräte GmbH, IPR2019–01469, Paper 6 at 8 (P.T.A.B. Feb. 13, 2020) (precedential); ANPRM, supra note 348, at 24511. 
435 See ANPRM, supra note 348, at 24511. 436 Id. at 24511 (citing Advanced Bionics). 437  Id. at 24511 (citing Becton, Dickinson & Co. v. B. Braun Melsungen AG at 24511 (citing Becton, Dickinson & Co. v. B. Braun Melsungen AG
, IPR2017–01586, Paper 8, at 17–18  IPR2017–01586, Paper 8, at 17–18 
(P.T.A.B. Dec. 15, 2017) (precedential as to Section III.C.5, first paragraph)). (P.T.A.B. Dec. 15, 2017) (precedential as to Section III.C.5, first paragraph)). 
432438 Id.  439 Discretionary Denial NPRM, supra note 348, at 28705. 
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same teaching relied upon in the [PTAB] petition.”440 It also provides that prior art is “meaningfully addressed” only “when [USPTO] has evaluated the art or arguments and articulated its consideration of the art or arguments in the record.”441  
The proposed rule provides that, even if USPTO meaningfully addressed prior art at an earlier time, an IPR may be instituted if the petitioner establishes material error by USPTO.442 USPTO explains that material error could include errors of law—such as incorrect claim term constructions—and overlooking teachings of the relevant prior art.443  
The PREVAIL Act would impose a bright-line rule that PTAB must reject an IPR or PGR petition “that presents prior art or an argument that is the same or substantially the same as prior art or an argument that previously was presented to the [USPTO].”444 The sponsors contend that this requirement would prevent “costly and inefficient” proceedings involving the same prior art already considered by USPTO.445 Critics argue that this bill would require PTAB to deny institution of IPRs involving any prior art that was previously “presented” to USPTO, whether or not USPTO had actually considered that prior art—potentially incentivizing patent applicants to “immunize” their patents against future challenges by disclosing more prior art references than the examiner can “meaningfully consider.”446 Id.  433 Id. 434 See id. (“For example, for the art to be deemed ‘previously addressed,’ the claims must have been distinguished over the art in the record where the art was the basis of a rejection where the rejection was withdrawn or overcome by an amendment, was distinguished in a notice of allowance, or was discussed during an examiner interview.”). By contrast, 35 U.S.C. § 325(d) would not apply based on “mere citation” of a prior art reference. See id. 
435 ANPRM, supra note 348, at 24512. 436 Id. 437 S. 2220, 118th Cong. §§ 4(c)(1)(E), 5(c)(3). 438 PREVAIL ACT FACT SHEET, supra note 387, at 3. 439 Matal Statement, supra note 392, at 10–11.  
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Serial Petitions 
Serial PTAB petitions refer to when a petitioner files a second IPR or PGR attacking the same 
Serial PTAB petitions refer to when a petitioner files a second IPR or PGR attacking the same 
patent claims it challenged in an earlier petition, after the preliminary response to the first patent claims it challenged in an earlier petition, after the preliminary response to the first 
petition.petition.
440447    
Based on the “potential for abuse” through “repeated attacks on patents,” PTAB precedent sets 
Based on the “potential for abuse” through “repeated attacks on patents,” PTAB precedent sets 
out several nonexclusive factors (sometimes called the out several nonexclusive factors (sometimes called the 
General Plastic factors) that it considers factors) that it considers 
in deciding whether to exercise its discretion to decline to institute a serial IPR.in deciding whether to exercise its discretion to decline to institute a serial IPR.
441448 Those factors  Those factors 
are are 
1. whether the same petitioner previously filed a petition directed to the same claims of the 
1. whether the same petitioner previously filed a petition directed to the same claims of the 
same patent;  
same patent;  
2.  whether  at  the  time  of  filing  of  the  first  petition  the  petitioner  knew  of  the  prior  art 
2.  whether  at  the  time  of  filing  of  the  first  petition  the  petitioner  knew  of  the  prior  art 
asserted in the second petition or should have known of it;  
asserted in the second petition or should have known of it;  
3. whether at the time of filing of the second petition the petitioner already received the 
3. whether at the time of filing of the second petition the petitioner already received the 
patent owner’s preliminary response to the first petition or received 
patent owner’s preliminary response to the first petition or received 
the Board’s[PTAB’s] decision  decision 
on whether to institute review in the first petition;  on whether to institute review in the first petition;  
4. the length of time that elapsed between the time the petitioner learned of the prior art 
4. the length of time that elapsed between the time the petitioner learned of the prior art 
asserted in the second petition and the filing of the second petition;  
asserted in the second petition and the filing of the second petition;  
 
440 Id. at 28705. 441 Id. 442 See id. at 28705. 443 See id. at 28700–01. 444 S. 2220, 118th Cong. §§ 4(c)(1)(E), 5(c)(3). 445 PREVAIL ACT FACT SHEET, supra note 390, at 3. 446 Matal Statement, supra note 395, at 10–11.  447 See ANPRM, supra note 348, at 24510. 448 Gen. Plastic Indus. Co. v. Canon Kabushiki Kaisha, IPR2016-01357, at 16–17 (P.T.A.B. Sept. 16, 2017) (precedential).  
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5. whether the petitioner provides adequate explanation for the time elapsed between the 
5. whether the petitioner provides adequate explanation for the time elapsed between the 
filings of multiple petitions directed to the same claims of the same patent;  
filings of multiple petitions directed to the same claims of the same patent;  
6. the finite resources of 
6. the finite resources of 
the Board[PTAB]; and  ; and  
7. the requirement under 35 U.S.C. § 316(a)(11) to issue a final determination not later than 
7. the requirement under 35 U.S.C. § 316(a)(11) to issue a final determination not later than 
1 year after the date on which the Director notices institution of review.
1 year after the date on which the Director notices institution of review.
442449  
The first factor essentially considers whether a subsequent petition should be considered a “serial 
The first factor essentially considers whether a subsequent petition should be considered a “serial 
petition” at all. In applying this factor, PTAB considers not only whether the named petitioner has petition” at all. In applying this factor, PTAB considers not only whether the named petitioner has 
previously petitioned to invalidate the claims at issue but also whether parties in “privity” with previously petitioned to invalidate the claims at issue but also whether parties in “privity” with 
the petitioner have done so.the petitioner have done so.
443450 PTAB has, for instance, exercised its discretion to deny a petition  PTAB has, for instance, exercised its discretion to deny a petition 
where one of the petitioner’s licensees—who was also the petitioner’s codefendant in a parallel where one of the petitioner’s licensees—who was also the petitioner’s codefendant in a parallel 
district court suit—had previously petitioned to cancel the same claims.district court suit—had previously petitioned to cancel the same claims.
444451 The first factor  The first factor 
likewise weighs against institution where the petitioner previously joined an already-instituted likewise weighs against institution where the petitioner previously joined an already-instituted 
IPR on the same patent claims.IPR on the same patent claims.
445  
In its ANPRM, USPTO stated that it is considering replacing the General Plastics factors with a rule that PTAB would deny institution of all serial IPRs that do not meet the two exceptions noted 
 
440 See ANPRM, supra note 348, at 24510. 441 Gen. Plastic Indus. Co. v. Canon Kabushiki Kaisha, IPR2016-01357, at 16–17 (P.T.A.B. Sept. 16, 2017) (precedential).  
442 Id. at 16. 443 ANPRM, supra note 348, at 24507. 444 Valve Corp. v. Elec. Scripting Prods., Inc., IPR2019-00062, -00063, -00084, 2019 WL 1490575 (P.T.A.B. Apr. 2, 2019) (precedential) (Valve I). 
445 See ANPRM, supra note 348, at 24507; Valve Corp. v. Elec. Scripting Prods., Inc., IPR2019-00064, -00065, -00085, 2019 WL 1965688 (P.T.A.B. May 1, 2019) (Valve II). 
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below.446 USPTO argues that this reform would provide “greater clarity and certainty to the parties regarding whether subsequent petitions will be instituted.”447  
Under the ANPRM, PTAB would deny a serial petition unless (1) the earlier petition was resolved for reasons not materially related to its merits, or (2) there are “exceptional circumstances.”448 Exceptional circumstances could, for instance, include scenarios where the patentee changes the asserted scope of their claims through amendment or a proposed claim construction, where the petitioner could not reasonably have found asserted prior art when they filed the first petition, or where the petitioner has a “justifiable explanation” for not having included a new statutory challenge in the earlier petition.449 
PTAB is also considering whether, as part of this reform, it would deny serial petitions filed by parties with a “substantial relationship” to previous petitioners—a standard that could encompass a broader range of related parties than the current “privity” test.450 For instance, membership organizations that file IPR petitions might be considered to have a “substantial relationship” with each of their constituent members.451452  
USPTO’s NPRM on discretionary denial issues defines a serial petition as one that challenges the “same or overlapping claims of the same patent that have already been challenged by the petitioner, the petitioner’s real party in interest, or a privy of the petitioner” and is filed after the time the patent owner files their preliminary response or, if no preliminary response is filed, the deadline for such response.453 The NPRM proposes a rule to codify “substantially the same factors” to evaluate serial petitions as General Plastics, with the goal of balancing the interests of “preventing undue harassment by patent owners” and “allowing petitioners reasonable opportunities to seek review.”454 The factors set forth in USPTO’s proposed rule, corresponding to the second through fifth General Plastics factors, are: 
(1) Whether, at the time of filing of the first petition, the petitioner knew of the prior art asserted in the second petition or should have known of it;  
(2) Whether, at the time of filing of the second petition, the petitioner had already received the  patent  owner  preliminary  response  to  the  first  petition  or  had  received  [PTAB’s] decision on whether to institute review in the first petition;  
(3) The length of time that elapsed between the time the petitioner learned of the prior art asserted in the second petition and the filing of the second petition; and  
(4) Whether the petitioner provided an adequate explanation for the time elapsed between the filings of multiple petitions directed to the same claims of the same patent.455  
The PREVAIL Act contains an estoppel provision that would generally prohibit serial petitions. 
The PREVAIL Act contains an estoppel provision that would generally prohibit serial petitions. 
The estoppel provision would generally prohibit a petitioner who has “previously requested” an The estoppel provision would generally prohibit a petitioner who has “previously requested” an 
IPR on any claim in a given patent, a real party in interest, or a privy of the petitioner to request IPR on any claim in a given patent, a real party in interest, or a privy of the petitioner to request 
or maintain another “proceeding” before USPTO on a ground that the petitioner “raised or or maintain another “proceeding” before USPTO on a ground that the petitioner “raised or 
reasonably could have raised” in the previous IPR petition.reasonably could have raised” in the previous IPR petition.
452456 The sole exception to this rule 
 
449 Id. at 16. 450 ANPRM, supra note 348, at 24507. 451 Valve Corp. v. Elec. Scripting Prods., Inc., IPR2019-00062, -00063, -00084, 2019 WL 1490575 (P.T.A.B. Apr. 2, 2019) (precedential) (Valve I). 
452 See ANPRM, supra note 348, at 24507; Valve Corp. v. Elec. Scripting Prods., Inc., IPR2019-00064, -00065, -00085, 2019 WL 1965688 (P.T.A.B. May 1, 2019) (Valve II). 
453 Discretionary Denial NPRM, supra note 348, at 28703. 454 Id. at 28699. 455 Id. at 28706. 456 S. 2220, 118th Cong. § 4(c)(1)(F). 
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 The sole exception to this rule applies where, after filing the initial IPR petition, the petitioner, party in interest, or privy is applies where, after filing the initial IPR petition, the petitioner, party in interest, or privy is 
“charged with infringement of additional claims of the patent” and requests a subsequent IPR “charged with infringement of additional claims of the patent” and requests a subsequent IPR 
solely on such additional claims.solely on such additional claims.
453457  
Parallel Petitions 
A distinct but similar practice to serial petitions, “parallel” PTAB petitions, refers to a petitioner 
A distinct but similar practice to serial petitions, “parallel” PTAB petitions, refers to a petitioner 
filing multiple IPRs and PGRs attacking the same patent on different grounds at filing multiple IPRs and PGRs attacking the same patent on different grounds at 
or about the same time.the same time.
454 458 One reason that petitioners sometimes file parallel petitions attacking the same patent is that One reason that petitioners sometimes file parallel petitions attacking the same patent is that 
PTAB rules impose limits on the length of each petition and subsequent briefing.PTAB rules impose limits on the length of each petition and subsequent briefing.
455 459 Thus, parallel Thus, parallel 
petitions allow the petitioner more space to explicate arguments for each ground for invalidation. petitions allow the petitioner more space to explicate arguments for each ground for invalidation. 
At the same time, USPTO notes that parallel petitions “may place a substantial and unnecessary At the same time, USPTO notes that parallel petitions “may place a substantial and unnecessary 
burden on the patent owner and could raise fairness, timing, and efficiency concerns.”burden on the patent owner and could raise fairness, timing, and efficiency concerns.”
456 
In the ANPRM, USPTO460 PTAB may deny institution of parallel petitions.461 
USPTO’s NPRM on discretionary denial issues defines parallel petitions as two or more petitions challenging the same patent that are filed on or before the time the patent owner files their preliminary response or, if no preliminary response is filed, the deadline for such response.462 The NPRM proposes a rule under which PTAB would not institute parallel petitions  proposes a rule under which PTAB would not institute parallel petitions 
unless the unless the 
petitioner shows “good cause as to why more than one petition is necessary.”463 The proposed rule provides that information relevant to a showing of good cause might include:  
(1) A petitioner’s ranking of their petitions in the order in which petitioner desires [PTAB] to consider the merits of their petitions relative to their other parallel petitions;  
(2) An explanation of the differences between the petitions and why the issues addressed by the differences are material;  
(3) The number of patent claims of the challenged patent that have been asserted by the patent owner in district court litigation;  
(4) The number of claims the petitioner is challenging;  
(5) Whether there is a dispute about the priority date of the challenged patent;  
(6)  Whether  there  are  alternative  claim  constructions  that  require  different  prior  art references on mutually exclusive grounds;  
(7) Whether the petitioner lacked information, such as the identity of asserted claims, at the time they filed the petitions;  
(8) The complexity of the technology in the case; and  
 
457 Id. § 4(c)(1)(F). 458 ANPRM, supra note 348, at 24512. 459petitioner shows “good cause” why PTAB should do so.457 The ANPRM also proposes 
 
446 ANPRM, supra note 348, at 24510–11. 447 Id. at 24511. 448 Id.  449 See id.  450 Id. at 24507. 451 Id. 452 S. 2220, 118th Cong. § 4(c)(1)(F). 453 Id. § 4(c)(1)(F). 454 ANPRM, supra note 348, at 24512. 455  See 37 C.F.R. § 42.24(A)(1)(i) (14,000 word limit for IPR petition), (ii) (18,700 word limit for PGR).  37 C.F.R. § 42.24(A)(1)(i) (14,000 word limit for IPR petition), (ii) (18,700 word limit for PGR). 
456460 ANPRM,  ANPRM, 
supra  notenote 348, at 24512. at 24512. 
457 Id. 
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allowing petitioners to pay a higher filing fee for an increased word-count limit to mitigate one common reason for filing parallel petitions.458 
The ANPRM notes that good cause to institute parallel petitions might be shown based on factors including  
(1) whether the 461 See CONSOLIDATED PTAB PRACTICE GUIDE, supra note 136, at 59–61 (“Based on [PTAB’s] experience, one petition should be sufficient to challenge the claims of a patent in most situations. . . . Nonetheless, [PTAB] recognizes that there may be circumstances in which more than one petition may be necessary, including, for example, when the patent owner has asserted a large number of claims in litigation or when there is a dispute about patent owner has asserted a large number of claims in the parallel [district court]  litigation;  (2)  whether  the  petitioner  is  challenging  a  large  number  of  claims;  (3) whether there is a dispute about a priority date requiring arguments under multiple prior priority date requiring arguments under multiple prior 
art references; (4) whether there are alternative claim constructions that require different prior  art  references  or  mutually  exclusive  grounds;  (5)  whether  the  petitioner  lacks sufficient  information  at  the  time  of  filing  the  petition,  e.g.,  the  patent  owner  has  not construed the claims or provided specific information as to the allegedly infringed claims; (6) whether there are a large number of claimed embodiments challenged, e.g., composition claims,  method  of  making  claims,  and  method  of  use  claims;  (7)  the  complexity  of  the technology in the case; and (8) the strength of the merits of the petition.459 
PTAB would allow the petitioner and respondent to file separate briefing to determine whether a petitioner had shown good cause to institute parallel petitions.460art references. In such cases two petitions by a petitioner may be needed, although this should be rare.”). 462 Discretionary Denial NPRM, supra note 348, at 28703. 463 Id. at 28706. 
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(9) Any other information believed to be pertinent to the good cause determination.464  
The same PREVAIL Act estoppel provision that would generally prohibit serial petitions
The same PREVAIL Act estoppel provision that would generally prohibit serial petitions
, as described above, would equally apply to prohibit parallel petitions. would equally apply to prohibit parallel petitions.
461465 Likewise, the sole  Likewise, the sole 
exception to that estoppel provision—for petitions attacking additional claims of the patent that exception to that estoppel provision—for petitions attacking additional claims of the patent that 
were asserted against the petitioner, parties-in-interest, and privies after the initial petition—were asserted against the petitioner, parties-in-interest, and privies after the initial petition—
would apply to both serial and parallel petitions.would apply to both serial and parallel petitions.
462466 The sponsors of the PREVAIL Act argue this  The sponsors of the PREVAIL Act argue this 
estoppel provision would reduce litigation costs and give patent owners “quiet title” to their IP.estoppel provision would reduce litigation costs and give patent owners “quiet title” to their IP.
463 467 Some opponents argue that this “single petition” requirement would make it “impossible to Some opponents argue that this “single petition” requirement would make it “impossible to 
effectively challenge patents” with a large number of claims or disputed priority dates, due to the effectively challenge patents” with a large number of claims or disputed priority dates, due to the 
applicable word-count limits on each petition.applicable word-count limits on each petition.
464468  
Parallel District Court Litigation 
In addition to serial and parallel petitions, PTAB must often determine whether to deny institution 
In addition to serial and parallel petitions, PTAB must often determine whether to deny institution 
of an IPR on patent claims that are subject to ongoing (“parallel”) district court litigation. In a of an IPR on patent claims that are subject to ongoing (“parallel”) district court litigation. In a 
2020 precedential decision, PTAB developed a multifactor test to determine whether to exercise 2020 precedential decision, PTAB developed a multifactor test to determine whether to exercise 
its discretion to deny an IPR in such cases.its discretion to deny an IPR in such cases.
465469 PTAB intended for these factors to help it determine  PTAB intended for these factors to help it determine 
“whether efficiency, fairness, and the merits support the exercise of authority to deny institution “whether efficiency, fairness, and the merits support the exercise of authority to deny institution 
in view of an earlier trial date in the parallel [court] proceeding.”in view of an earlier trial date in the parallel [court] proceeding.”
466470    
The six factors that PTAB is to take into account—known as the 
The six factors that PTAB is to take into account—known as the 
Fintiv factors—are  factors—are 
1.  whether  the  court  granted  a  stay  or  evidence  exists  that  one  may  be  granted  if  a 
1.  whether  the  court  granted  a  stay  or  evidence  exists  that  one  may  be  granted  if  a 
proceeding is instituted; 
proceeding is instituted; 
 
458 Id. at 24513. 459 Id. 460 See id. 461 See S. 2220, 118th Cong. § 4(c)(1)(F); see also PREVAIL ACT FACT SHEET, supra note 387
2. proximity of the court’s trial date to [PTAB’s] projected statutory deadline for a final 
written decision; 
3. investment in the parallel proceeding by the court and the parties; 
4. overlap between issues raised in the petition and in the parallel proceeding; 
5. whether the petitioner and the defendant in the parallel proceeding are the same party; 
and 
6.  other  circumstances  that  impact  the  [PTAB’s]  exercise  of  discretion,  including  the 
merits.471 
In June 2022, USPTO released statistics showing that the number and percentage of Fintiv denials peaked in the first half of FY2021 (with over 10% of all petitions being denied under the Fintiv factors) before declining sharply afterward.472 Contemporaneous with the study, USPTO 
 
464 Id. 465 See S. 2220, 118th Cong. § 4(c)(1)(F); see also PREVAIL ACT FACT SHEET, supra note 390, at 2 (noting that this at 2 (noting that this 
provision “appl[ies] estoppel at the time the [first] challenge is filed”).  provision “appl[ies] estoppel at the time the [first] challenge is filed”).  
462466  See S. 2220, 118th Cong. § 4(c)(1)(F).   S. 2220, 118th Cong. § 4(c)(1)(F).  
463467 PREVAIL ACT FACT SHEET,  PREVAIL ACT FACT SHEET, 
supra  note 387note 390, at 2. at 2. 
464468 Matal Statement,  Matal Statement, 
supra  note 392note 395, at 8. at 8. 
465469  See Apple v. Fintiv, IPR2020-00019, at 5 (P.T.A.B. Mar. 20, 2020) (designated precedential May 5, 2020).  Apple v. Fintiv, IPR2020-00019, at 5 (P.T.A.B. Mar. 20, 2020) (designated precedential May 5, 2020).  
466470  Fintiv, IPR2020-00019, at 6. , IPR2020-00019, at 6. 
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2. proximity of the court’s trial date to the Board’s projected statutory deadline for a final 
written decision; 
3. investment in the parallel proceeding by the court and the parties; 
4. overlap between issues raised in the petition and in the parallel proceeding; 
5. whether the petitioner and the defendant in the parallel proceeding are the same party; 
and 
6.  other  circumstances  that  impact  the  Board’s  exercise  of  discretion,  including  the 
merits.467 
In June 2022, USPTO released statistics showing that the number and percentage of Fintiv denials peaked in the first half of FY2021 (with over 10% of all petitions being denied under the Fintiv factors) before declining sharply afterward.468 Contemporaneous with the study, USPTO 471 Id. 472 See USPTO, PATENT TRIAL AND APPEAL BOARD PARALLEL LITIGATION STUDY (June 2022), https://www.uspto.gov/sites/default/files/documents/ptab_parallel_litigation_study_20220621_.pdf?utm_campaign=subscriptioncenter&utm_content=&utm_medium=email&utm_name=&utm_source=govdelivery&utm_term=. 
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Director Vidal issued a binding guidance memorandum (the Guidance Memo) making four main Director Vidal issued a binding guidance memorandum (the Guidance Memo) making four main 
clarifications to how PTAB should apply the clarifications to how PTAB should apply the 
Fintiv factors. factors.
469473    
The Guidance Memo narrows or eliminates circumstances in which PTAB might otherwise deny 
The Guidance Memo narrows or eliminates circumstances in which PTAB might otherwise deny 
institution based on institution based on 
Fintiv. First, as a gloss on factor six, the Guidance Memo states that PTAB . First, as a gloss on factor six, the Guidance Memo states that PTAB 
should not deny institution under should not deny institution under 
Fintiv if the petition “presents compelling evidence of  if the petition “presents compelling evidence of 
unpatentability,”unpatentability,”
470474 meaning evidence that, “if unrebutted in trial, would plainly lead to a  meaning evidence that, “if unrebutted in trial, would plainly lead to a 
conclusion that one or more claims are unpatentable by a preponderance of the evidence.”conclusion that one or more claims are unpatentable by a preponderance of the evidence.”
471475  Second, the Guidance Memo clarified that, contrary to some past practice by PTAB, Second, the Guidance Memo clarified that, contrary to some past practice by PTAB, 
Fintiv  applies only to parallel district court litigation and should not be applied to deny institution due to applies only to parallel district court litigation and should not be applied to deny institution due to 
parallel proceedings in the ITC.parallel proceedings in the ITC.
472476 Third, the Guidance Memo clarified that, under factor four,  Third, the Guidance Memo clarified that, under factor four, 
PTAB will not deny institution based on parallel district court litigation if the petitioner stipulates PTAB will not deny institution based on parallel district court litigation if the petitioner stipulates 
that they will not assert the same invalidity grounds in the district court case.that they will not assert the same invalidity grounds in the district court case.
473477 Fourth, the  Fourth, the 
Guidance Memo clarified that factor two does not always weigh in favor of denial where the Guidance Memo clarified that factor two does not always weigh in favor of denial where the 
district court’s scheduled trial date is prior to PTAB’s projected deadline for a final written district court’s scheduled trial date is prior to PTAB’s projected deadline for a final written 
decision, given that scheduled trial dates may be “unreliable and subject to change.”decision, given that scheduled trial dates may be “unreliable and subject to change.”
474478 Some  Some 
observers note that the number of observers note that the number of 
Fintiv denials declined following the Guidance Memo. denials declined following the Guidance Memo.
475479  
In 
In 
theits April 2023 ANPRM, USPTO  ANPRM, USPTO 
proposesproposed replacing the  replacing the 
Fintiv factors with a “clear, predictable rule” to  factors with a “clear, predictable rule” to 
streamline its decisions whether to institute an IPR on a patent involved in parallel district streamline its decisions whether to institute an IPR on a patent involved in parallel district 
court litigation.480 Under this approach, PTAB would have denied institution of any IPR if there were parallel district court litigation involving at least one of the challenged claims if PTAB determined the district court trial was “likely to occur” before the statutory deadline for the final written decision in the IPR.481 In addition, the ANPRM proposed adopting a “streamlined version” of some of the Fintiv factors in order to avoid “an unduly harsh outcome” in certain cases.482 Finally, the ANPRM proposed “safe harbors” that would have precluded discretionary denial where the petitioner filed a stipulation “agreeing not to pursue potentially overlapping grounds in district court” or where the parallel district court proceeding had been stayed (i.e., paused by the court).483  
 
473court 
 
467 Id. 468 See USPTO, PATENT TRIAL AND APPEAL BOARD PARALLEL LITIGATION STUDY (June 2022), https://www.uspto.gov/sites/default/files/documents/ptab_parallel_litigation_study_20220621_.pdf?utm_campaign=subscriptioncenter&utm_content=&utm_medium=email&utm_name=&utm_source=govdelivery&utm_term=. 
469 USPTO, Memorandum to Members of PTAB Regarding Interim Procedure for Discretionary Denials in AIA Post- USPTO, Memorandum to Members of PTAB Regarding Interim Procedure for Discretionary Denials in AIA Post-
Grant Proceedings With Parallel District Court Litigation 2 (June 2022), Grant Proceedings With Parallel District Court Litigation 2 (June 2022), 
https://www.uspto.gov/sites/default/files/documents/interim_proc_discretionary_denials_aia_parallel_district_court_litihttps://www.uspto.gov/sites/default/files/documents/interim_proc_discretionary_denials_aia_parallel_district_court_liti
gation_memo_20220621_.pdf?utm_campaign=subscriptioncenter&utm_content=&utm_medium=email&utm_name=&gation_memo_20220621_.pdf?utm_campaign=subscriptioncenter&utm_content=&utm_medium=email&utm_name=&
utm_source=govdelivery&utm_term=. utm_source=govdelivery&utm_term=. 
470474  Id. at 5. at 5. 
471475  Id. at 4.  at 4. 
472476  See id. at 6 (noting that, “[u]nlike district courts, the ITC lacks authority to invalidate a patent and its invalidity  at 6 (noting that, “[u]nlike district courts, the ITC lacks authority to invalidate a patent and its invalidity 
rulings are not binding on either the [USPTO] or a district court). rulings are not binding on either the [USPTO] or a district court). 
473477  See id. at 7 (citing  at 7 (citing 
Sotera Wireless, Inc. v. Masimo Corporation (§ II.A), IPR2020-01019, Paper 12 (Dec. 1, 2020)  (§ II.A), IPR2020-01019, Paper 12 (Dec. 1, 2020) 
(designated precedential Dec. 17, 2020)). (designated precedential Dec. 17, 2020)). 
474478  Id. at 8.  at 8. 
475479  See Armond Statement,  Armond Statement, 
supra no no
te 403, at 10. 
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litigation.476 Under this rule, PTAB would deny institution of any IPR if there is parallel district court litigation involving at least one of the challenged claims if PTAB determines the district court trial is “likely to occur” before the statutory deadline for the final written decision in the IPR.477 USPTO is considering various methods by which PTAB could make such a likeliness determination.478 
The ANPRM raises the possibility that USPTO might, in addition to the “predictable rule” above, adopt a “streamlined version” of some of the existing Fintiv factors in order to avoid “an unduly harsh outcome” in certain cases. The streamlined factors would be 
(1) [p]ast and future expected investment in the parallel proceeding by the district court and the parties [similar to Fintiv factor three]; 
(2) [t]he degree of overlap between the issues in the petition and the parallel district court proceeding [similar to Fintiv factor four]; and 
(3) [a]ny other circumstances that the parties contend are relevant to the Board’s exercise of discretion [similar to Fintiv factor six].479 
USPTO notes that, even if it adopts such a streamlined version of the Fintiv factors, it expects that the “predictable” rule described above would “control the vast majority of discretionary issues” without the need to consider the streamlined factors.480 
Finally, the ANPRM notes that, regardless of whether the “predictable” rule is adopted alone or in combination with a revised version of the Fintiv factors, USPTO proposes to adopt two “safe harbors” that would preclude discretionary denial on the basis of 406, at 10. 480 ANPRM, supra note 348, at 24514. 481 Id. at 24515.  482 Id. at 24516. 483 Id. at 24515–16. 
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In the April 2024 NPRM on discretionary denial issues, USPTO did not propose rules concerning parallel district court parallel district court 
litigation.481 First, USPTO is considering a safe harbor for cases in which the petitioner files a stipulation “agreeing not to pursue potentially overlapping grounds in district court,” similar to its current practice.482 Second, USPTO is considering a rule not to deny institution on the basis of a parallel district court proceeding that has been stayed (i.e., paused) and “is reasonably expected to remain stayed” at least until the deadline for PTAB’s decision whether to institute.483litigation. USPTO noted that it “continues to consider issuing proposed rules” on issues raised in the ANPRM.484  
The PREVAIL Act aims to “[e]nd duplicative patent challenges” that result from challengers 
The PREVAIL Act aims to “[e]nd duplicative patent challenges” that result from challengers 
“raising the same or similar validity challenges” both at PTAB and in district court.“raising the same or similar validity challenges” both at PTAB and in district court.
484485 Thus, the  Thus, the 
“single forum” provision in the PREVAIL Act would prevent the petitioner, a real party in “single forum” provision in the PREVAIL Act would prevent the petitioner, a real party in 
interest, or a privy of the petitioner from maintaining a challenge to the validity of a patent on any interest, or a privy of the petitioner from maintaining a challenge to the validity of a patent on any 
35 U.S.C.35 U.S.C.
 § 311(b) grounds (i.e., anticipation or obviousness in light of prior art patents and § 311(b) grounds (i.e., anticipation or obviousness in light of prior art patents and 
printed publications) in a district court or ITC proceeding once an IPR is instituted on that printed publications) in a district court or ITC proceeding once an IPR is instituted on that 
patent.patent.
485486 Proponents argue that this change would “more closely align” PTAB’s practice with  Proponents argue that this change would “more closely align” PTAB’s practice with 
“the policy goal of streamlining patent invalidity litigation and avoiding lengthy duplicate “the policy goal of streamlining patent invalidity litigation and avoiding lengthy duplicate 
invalidity disputes.”invalidity disputes.”
486487 Some opponents argue that concerns about duplicative litigation would be  Some opponents argue that concerns about duplicative litigation would be 
better addressed by legislation requiring parallel district court litigation to be stayed if an IPR is better addressed by legislation requiring parallel district court litigation to be stayed if an IPR is 
 
476 ANPRM, supra note 348, at 24514. 477 Id. at 24515.  478 See id. 479 Id. at 24516. 480 Id. 481 See id. at 24515. 482 Id. 483 Id. at 24516. 484 PREVAIL ACT FACT SHEET, supra note 387, at 2.  485 See S. 2220, 118th Cong. § 4(c)(1)(C). 486 Armond Statement, supra note 403, at 10. 
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instituted, since doing so could avoid costly district court litigation on patent claims that may be instituted, since doing so could avoid costly district court litigation on patent claims that may be 
invalidated.invalidated.
487488  
Patent Claims Already Upheld by a District Court 
A final circumstance involves patents claims that have already been upheld as valid in district 
A final circumstance involves patents claims that have already been upheld as valid in district 
court litigation. Currently, PTAB may choose to initiate or continue IPR proceedings after a court litigation. Currently, PTAB may choose to initiate or continue IPR proceedings after a 
district court has already ruled on the validity of the patent at issue. One example involved a district court has already ruled on the validity of the patent at issue. One example involved a 
patent owner that successfully sued Apple in district court for infringing its patents relating to patent owner that successfully sued Apple in district court for infringing its patents relating to 
virtual private networks (VPNs).virtual private networks (VPNs).
488489 In 2014, the Federal Circuit upheld the district court’s  In 2014, the Federal Circuit upheld the district court’s 
decision that the patents were valid.decision that the patents were valid.
489490 Two years later, however, PTAB found that the same  Two years later, however, PTAB found that the same 
patents were invalid.patents were invalid.
490491 This year, the Federal Circuit affirmed PTAB’s decision and vacated the  This year, the Federal Circuit affirmed PTAB’s decision and vacated the 
$576 million judgment against Apple. The Federal Circuit held this was consistent with its 2014 $576 million judgment against Apple. The Federal Circuit held this was consistent with its 2014 
decision because PTAB is entitled to find invalidity under a more permissive “preponderance of decision because PTAB is entitled to find invalidity under a more permissive “preponderance of 
evidence” standard (as noted above).evidence” standard (as noted above).
491 
The ANPRM proposes492 
USPTO’s April 2023 ANPRM proposed changing PTAB’s practice such that PTAB would generally deny petitions  changing PTAB’s practice such that PTAB would generally deny petitions 
challenging claims that “substantially overlap” with claims that have already been upheld by a challenging claims that “substantially overlap” with claims that have already been upheld by a 
“final adjudication” in district court.“final adjudication” in district court.
492493 The ANPRM would  The ANPRM would 
providehave provided an exception for petitioners  an exception for petitioners 
who (1) either who (1) either 
havehad standing to challenge the claims in district court  standing to challenge the claims in district court 
or  intendintended to pursue  to pursue 
commercialization of a product or service in the same field, (2) were not a real party in interest or commercialization of a product or service in the same field, (2) were not a real party in interest or 
privy to the party previously challenging the claims unless the earlier petition was resolved for reasons not materially related to the merits, and (3) meet a higher burden of “compelling merits.”493 
The PREVAIL Act’s sponsors assert that instituting or maintaining PTAB proceedings following a district court decision on validity leads to inefficiency and inconsistent decisions.494 Thus, the PREVAIL Act would require PTAB to deny institution—as well as dismiss proceedings already in progress—if a district court or the ITC has already entered a final judgment deciding a challenge to the validity of the same patent claim on any Section 311(b) grounds in a case in which the petitioner, a real party in interest, or a privy of the petitioner was a party.495 Opponents argue that district courts are not an “adequate substitute” for PTAB review, given PTAB’s technical expertise compared with district courts and juries,496 and thus that “district court validity decisions are insufficiently reliable to serve as the final word on patent validity.”497 
 
487 Matal Statement, supra note 392, at 15. 488privy to the party previously challenging the claims unless 
 
484 Discretionary Denial NPRM, supra note 348, at 28695. 485 PREVAIL ACT FACT SHEET, supra note 390, at 2.  486 See S. 2220, 118th Cong. § 4(c)(1)(C). 487 Armond Statement, supra note 406, at 10. 488 Matal Statement, supra note 395, at 15. 489  See VirnetX Inc. v. Cisco Sys., 767 F.3d 1308, 1313–14 (Fed. Cir. 2014).  VirnetX Inc. v. Cisco Sys., 767 F.3d 1308, 1313–14 (Fed. Cir. 2014). 
489490  See id. at 1324.  at 1324. 
490491 VirnetX Inc. v. Mangrove Partners Master Fund, Nos. 2020-2271, 2272, 2023 WL 2708975, at *3 (Fed. Cir. Mar.  VirnetX Inc. v. Mangrove Partners Master Fund, Nos. 2020-2271, 2272, 2023 WL 2708975, at *3 (Fed. Cir. Mar. 
30, 2023), 30, 2023), 
cert. denied, No. 23-315, 2024 WL 674719 (U.S. Feb. 20, 2024). , No. 23-315, 2024 WL 674719 (U.S. Feb. 20, 2024). 
491492  Id. at *8 n.8.  at *8 n.8. 
492493 ANPRM,  ANPRM, 
supra  notenote 348, at 24510 (noting finality would be defined consistent with 28 U.S.C. § 1295(a)(1)).  at 24510 (noting finality would be defined consistent with 28 U.S.C. § 1295(a)(1)).  
493 ANRPM, supra note 348, at 23510.  494 See PREVAIL ACT FACT SHEET, supra note 387, at 3. 495 See S. 2220, 118th Cong. § 4(c)(1)(G). 496 See Matal Statement, supra note 392, at 3–5. 497 Id. at 18. 
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the earlier petition was resolved for reasons not materially related to the merits, and (3) met a higher burden of “compelling merits.”494  
In the April 2024 NPRM on discretionary denial issues, USPTO did not propose rules concerning patent claims already upheld by a district court. USPTO noted that it “continues to consider issuing proposed rules” on issues raised in the ANPRM.495 
The PREVAIL Act’s sponsors assert that instituting or maintaining PTAB proceedings following a district court decision on validity leads to inefficiency and inconsistent decisions.496 Thus, the PREVAIL Act would require PTAB to deny institution—as well as dismiss proceedings already in progress—if a district court or the ITC has already entered a final judgment deciding a challenge to the validity of the same patent claim on any Section 311(b) grounds in a case in which the petitioner, a real party in interest, or a privy of the petitioner was a party.497 Opponents argue that district courts are not an “adequate substitute” for PTAB review, given PTAB’s technical expertise compared with district courts and juries,498 and thus that “district court validity decisions are insufficiently reliable to serve as the final word on patent validity.”499 
Conclusion 
Since its creation in 2011, PTAB has become one of the more significant—and controversial—Since its creation in 2011, PTAB has become one of the more significant—and controversial—
aspects of the U.S. patent system. IPR, in particular, has become one of the most common ways aspects of the U.S. patent system. IPR, in particular, has become one of the most common ways 
to determine the validity of issued patents. Patent law stakeholders thus often have strong views to determine the validity of issued patents. Patent law stakeholders thus often have strong views 
on the procedural and substantive workings of PTAB and IPR. Current proposals for PTAB on the procedural and substantive workings of PTAB and IPR. Current proposals for PTAB 
include maintaining the tribunal as it exists, modifying IPR and PGR procedures, or abolishing include maintaining the tribunal as it exists, modifying IPR and PGR procedures, or abolishing 
PTAB entirely. In weighing these options, Congress may consider whether the tribunal is PTAB entirely. In weighing these options, Congress may consider whether the tribunal is 
effectively serving its intended purpose of improving patent quality by providing an efficient effectively serving its intended purpose of improving patent quality by providing an efficient 
means of determining patent validity issues—or if, instead, AIA proceedings are unfair to patent means of determining patent validity issues—or if, instead, AIA proceedings are unfair to patent 
holders and create undue uncertainty in patent rights.  holders and create undue uncertainty in patent rights.  
 
 
Author Information 
 
 Christopher T. Zirpoli Christopher T. Zirpoli 
  Kevin J. Hickey 
  Kevin J. Hickey 
Legislative Attorney 
Legislative Attorney 
Legislative Attorney 
Legislative Attorney 
    
    
    
    
 
 
494 ANRPM, supra note 348, at 23510.  495 Discretionary Denial NPRM, supra note 348, at 28695. 496 See PREVAIL ACT FACT SHEET, supra note 390, at 3. 497 See S. 2220, 118th Cong. § 4(c)(1)(G). 498 See Matal Statement, supra note 395, at 3–5. 499 Id. at 18. 
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This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan 
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Congressional Research Service  
Congressional Research Service  
R48016
R48016
 · VERSION 1 · NEW 
483 · UPDATED 
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