Recent Policy Changes Shield Some Older AI Patents From Patent Office Trials as Challengers Move to Reexamination

The Supreme Court left the USPTO's patent-age denials of inter partes review in place on October 19. Meanwhile, challengers have moved to ex parte reexamination, where, regardless of age, the Office decides to reexamine a patent if prior art patents and publications submitted by a requester raise a substantial new question of patentability.

The Supreme Court denied certiorari in Google LLC v. VirtaMove Corp., No. 25-1230, on October 19, 2026, without comment. The denial leaves in place the Federal Circuit's January 27, 2026 nonprecedential order, No. 2026-111, refusing Google's request for a writ of mandamus directing the U.S. Patent and Trademark Office (USPTO or the Office) to institute an inter partes review (IPR). In the IPR petition, Google asked the Patent Trial and Appeal Board (PTAB or the Board) to cancel claims of a VirtaMove patent on container software over prior patents and printed publications.

The Office had denied review because the challenged patent had "been in force for more than 14 years, creating strong settled expectations." Settled expectations is the Office's term for the reliance interest a patent owner builds as a patent goes unchallenged over time.

The denial of certiorari by the Supreme Court leaves the merits undecided. No court has yet decided whether the patent statutes permit the Office to deny institution on settled-expectations grounds. The Federal Circuit has so far rejected each route to review presented to the court, while stating in In re Cambridge Industries USA Inc., No. 2026-101 (Fed. Cir. Dec. 9, 2025) (nonprecedential), that the court does "not decide whether the PTO's actions are correct or whether the use of this [settled-expectations] factor is permitted under the statutes."

Challengers have shifted most post-grant filings to ex parte reexamination, a proceeding in which a USPTO examiner reconsiders an issued patent over prior patents and printed publications cited in a request filed by a third party, the requester. Reexamination typically costs less than an IPR, and the requester's role is smaller. An IPR is a trial-like proceeding before the PTAB in which the petitioner files the petition, replies to the patent owner's response, takes part in limited discovery, and participates in an oral hearing. In reexamination, the requester files the request and has only limited opportunities to reply, and the proceeding is otherwise similar to regular patent examination between the patent owner and an examiner in a specialized reexamination unit.

For companies owning or challenging AI patents, the age of the patent affects the available options. An older patent's age is one factor the Office can weigh in denying institution of an IPR, but a reexamination request turns on whether the cited prior patents and printed publications raise a substantial new question of patentability. Section 303(a) does not make patent age part of the substantial-new-question inquiry, so an older patent remains open to a prior-art challenge in reexamination.

The Supreme Court Left the Reviewability Question Open for Four Pending Petitions

Before the VirtaMove denial, five petitions asked the Supreme Court whether courts may review the USPTO Director's IPR institution decisions, or the rules behind them. The denial resolves one. Four others remain.

Two obstacles stand between these petitions and a ruling on the merits. Section 314(d) of the Patent Act makes the Director's determination whether to institute an IPR "final and nonappealable." Mandamus adds another obstacle: the petitioner must show a clear and indisputable right to relief. In VirtaMove, the Solicitor General recast the question presented as "[w]hether the court of appeals abused its discretion in declining to grant a writ of mandamus," and the government's brief in Tesla calls the petition's failure to engage the mandamus burden "an independently sufficient reason for this Court to deny certiorari." The mandamus burden gives the Court a way to deny review without construing Section 314(d). An APA plaintiff faces no mandamus burden but must show that Section 314(d) does not bar the suit.

The four petitions take different routes to the Court:

• Intel Corp. v. Squires, No. 26-73, is an Administrative Procedure Act (APA) suit challenging the Fintiv factors, the Board's test for denying institution when a parallel trial is likely to finish first. The suit challenges the rule and no individual denial, so the petition presents the Section 314(d) question without the mandamus burden. The government argues that Section 314(d) and the Patent Act's scheme bar the suit, that the Director now decides institution so the Fintiv factors carry little binding force, and that the petitioners' standing is questionable. The government filed its brief in opposition on October 14.
• Tesla, Inc. v. Granite Vehicle Ventures LLC, No. 26-136, seeks mandamus review of a denial based on the time-to-trial factor, and so faces the mandamus burden. The government filed its opposition on September 25, and Tesla replied on October 13.
• Kahoot! AS v. Interstellar Inc., No. 26-198, seeks mandamus review of a settled-expectations denial, on a patent in force just over six years. Kahoot! is the only pending petition challenging a settled-expectations denial, and like Tesla, the petition faces the mandamus burden. The government filed its opposition on October 16.
• Federal Express Corp. v. Qualcomm Inc., No. 26-170, is a patent owner's petition asking whether Section 314(d) also bars review of the Board's refusal to decide whether an IPR petition identified all real parties in interest, that is, the entities that fund or control a challenge. Responses are due October 28.

The Court's dispositions of Intel and Kahoot! may indicate, respectively, whether the Court is willing to decide the scope of Section 314(d) outside mandamus and whether the Court will decide the settled-expectations question itself despite the mandamus burden.

Settled Expectations Protects Older AI Patents Only at the IPR Institution Stage

The Office has not adopted a fixed age at which settled expectations favors denial. In Dabico Airport Solutions Inc. v. AXA Power ApS, IPR2025-00408, Paper 21 (June 18, 2025), Acting Director Coke Morgan Stewart denied institution on a patent "in force almost eight years," explaining that "in general, the longer the patent has been in force, the more settled expectations should be." The Office has also relied on the factor for a patent in force just over six years in Kahoot! and for a patent in force more than 14 years in VirtaMove, without announcing a threshold. In written testimony to a Senate subcommittee, Director Squires stated that no single discretionary consideration is dispositive and described recently instituting an IPR on a patent more than 20 years old.

Many patents asserted against generative AI products claim priority to applications filed years before those products reached the market, as suits against OpenAI, Anthropic, and Microsoft illustrate. The older patents in those suits are the patents settled expectations tends to protect most. By contrast, many patents claiming implementations and uses of generative AI issue from applications filed after ChatGPT reached the market in late 2022, so the patent-age factor offers those patents little support. A practitioner analysis of Office decisions from June through August 2025 found that nearly all patents in force four years or less were referred for an institution decision, although the Office's other discretionary factors still apply.

IPR institution rose in the third quarter, but on a small number of decisions. According to a third-quarter 2026 report from Unified Patents, a membership-funded company that challenges patents on behalf of its members, the Board instituted review in 55 of 96 IPR institution decisions, a 57.3% rate and the highest quarterly rate since the first quarter of 2025. The 96 decisions were the fewest in any quarter since the third quarter of 2013, and Unified puts the institution rate for the first year of Director John Squires's administration at around 40%.

At a September 29 Senate oversight hearing, Director Squires's written testimony stated an announced intention to return merits institution determinations to the Board in October. As reported from the hearing, Director Squires told Senator Coons the Director would keep "the discretionary portion" and return "the merits portion to the panels." The merits portion asks whether the petitioner has a reasonable likelihood of prevailing, and the discretionary portion covers other reasons for denial, such as patent age. As of now, the USPTO has not published a notice implementing the announced change. Because settled expectations is a discretionary consideration, settled-expectations denials would presumably remain with the Director.

Challengers Have Moved Most Post-Grant Filings to Reexamination

Unified Patents reports that ex parte reexamination accounted for 71.9% of post-grant filings from January through September 2026, compared with 27.7% in the same period of 2025. Reexamination did not offset the decline in IPR petitions. Combined filings across reexamination, IPR, and post-grant review fell 27.2% year over year, and the third quarter's 304 combined filings were the lowest quarterly total in Unified's data.

The quarterly figures show the gap between reexamination requests and PTAB petitions narrowing. The third quarter of 2026 brought 198 reexamination requests and 106 PTAB petitions, compared with a record 331 requests and 70 petitions in the second quarter. Reexamination's share of post-grant filings fell from 82.5% in the second quarter to 65.1% in the third.

The volume of requests has produced a backlog at the Central Reexamination Unit (CRU), the USPTO examining group that handles reexamination. On September 30, the CRU had 1,354 open proceedings, more than twice the 624 matters pending at the PTAB, and Unified counted 52 active CRU examiners in the third quarter, down from 65 to 72 per quarter in 2023 and 2024. Section 303(a) of the Patent Act requires the Office to decide within three months of filing whether a request raises a substantial new question of patentability. The Office is still meeting that three-month deadline, but the median time to decision for requests filed in the second quarter of 2026 was 68 days, against 42 days over 2015 through 2024.

Unified Patents is also a participant in the shift the report measures. Unified filed 14 identified reexamination requests in the third quarter, the most of any requester, and filed amicus briefs supporting the Google and Intel petitions.

Reexamination Is Limited to Published Prior Art Grounds and Leaves Eligibility to the Courts

Under 35 U.S.C. § 303(a), the USPTO orders reexamination only if a request raises a "substantial new question of patentability," and the grounds must be based on prior patents or printed publications. Once reexamination is ordered, an examiner reexamines the challenged claims in a proceeding between the patent owner and the examiner. Under 35 U.S.C. § 304, the requester's only further filing is a reply to any statement the patent owner files, which is due within two months of service of the statement.

Much machine-learning research appears in forms that can qualify as printed publications when publicly accessible, including conference papers, journal articles, and preprints. Prior sales and deployed systems do not themselves support a request, and open-source code supports a request only if it qualifies as a printed publication. Patent subject matter eligibility is also not a ground for reexamination.

The move to reexamination therefore shifts prior-art validity disputes to the CRU while challenges to AI patents based on system prior art, eligibility, and enablement remain in federal district court.

Patent Owners Now Have 30 Days to Answer a Reexamination Request Before the Office Rules

Until April 2026, the Office decided whether a reexamination request raised a substantial new question of patentability by looking at the request alone. The USPTO now permits a patent owner to file a response to the request before the Office decides, as announced in 1545 Off. Gaz. 217 (Apr. 28, 2026). The pre-order procedure applies to requests filed on or after April 5, 2026.

The response must be filed within 30 days of service of the request and is limited to 30 pages, with no petition or fee required. The Official Gazette notice directs that the response be limited to arguments and facts supporting the patent owner's position that, despite the teachings argued in the request, the Office should maintain the patentability decision made during examination. A noncompliant response may be refused consideration. Arguments for discretionary denial under 35 U.S.C. § 325(d) can be made in a later stage, after the Office orders reexamination. A requester ordinarily may not respond to the patent owner, but may petition, with a fee, to file a reply of up to 10 pages within 15 days of service in exceptional circumstances, such as alleged misrepresentations of fact or law.

The early data shows limited effect from pre-order responses. Unified Patents found that patent owners filed pre-order responses in 109 of 274 eligible requests (39.8%). The CRU denied 14.8% of requests filed from April 5 on with a patent owner response (22 of 149) and 14.0% of those without one (25 of 178), compared with 5.6% (53 of 948) for requests filed from January 2025 through April 4, 2026. Unified attributes the higher denial rate to more demanding CRU review overall rather than to the pre-order responses. The CRU still orders reexamination in roughly six of every seven requests.

For patent owners, the pre-order response is the first opportunity to show the Office why the cited art does not present a new question before an examiner reexamines the claims. Unified's data show the denial rate rising for all requests, with or without a patent owner response.

A Proposed Rule Would Require Reexamination Requesters to Name Real Parties in Interest

The USPTO has proposed a new rule: 37 C.F.R. § 1.510(b)(7). The rule would require every third-party reexamination request to include a statement identifying all real parties in interest. Requirement To Identify All Real Parties in Interest to a Third Party Request for an Ex Parte Reexamination, 91 Fed. Reg. 46038 (July 22, 2026). The Office explains the statement would allow the estoppel provisions of 35 U.S.C. §§ 315(e)(1) and 325(e)(1) to be applied to reexaminations. After a final written decision in an IPR or post-grant review, the estoppel provisions bar the petitioner, its real parties in interest, and its privies from requesting or maintaining a proceeding before the Office on any ground the petitioner raised or reasonably could have raised in the review. On the requester's written request, the statement would be excluded from the patent and reexamination files and kept confidential. The comment period closed August 21, and the Office has not yet issued a final rule.

Anonymous requests are increasing. Unified Patents reports that the requester was unidentified on 35 of the 198 reexamination requests filed in the third quarter (18%), up from 6% in the first half of 2026. Because the proposed statement could be kept confidential, the rule as proposed would give the Office, but not necessarily the patent owner, the identity of the parties behind a request.

AI Patent Owners Anticipating Litigation Can Prepare for Patent Office and Court Challenges

Docket the Response Deadline From the Date of Service

Before asserting a patent, or when litigation appears likely, patent owners may face a reexamination request in response. A requester serves the request on the patent owner at the correspondence address of record under 37 C.F.R. § 1.33(c), and the 30-day response period runs from that service and cannot be extended. Patent owners should confirm that the address of record is current and that the counsel receiving service can act on a request promptly. For complex patents with numerous claims at issue, the response can be time-consuming to prepare.

Coordinate the Response With Positions in the Litigation

A patentee's statements during reexamination can be considered during claim construction under the doctrine of prosecution disclaimer. Krippelz v. Ford Motor Co., 667 F.3d 1261, 1266 (Fed. Cir. 2012). Counsel responding to a request should review the response against the claim constructions and infringement positions the patent owner has taken or expects to take in court, as arguments that distinguish the cited art can narrow claim scope in the litigation.

Document the Facts Supporting Settled Expectations

For older patents that may face an IPR, preserve records of commercialization, licensing, patent marking, and investment, and of communications showing that competitors had notice of the patents. Dabico treats patent age as the starting point, and the Office has weighed the additional facts in deciding whether to deny institution. Some of these records may also support secondary considerations of nonobviousness if the Office institutes review or orders reexamination.

Evaluate Eligibility Separately

An older AI patent may receive favorable treatment under the settled-expectations analysis while remaining exposed to a subject matter eligibility challenge in district court. The risk may be greatest for older machine-learning patents with broadly functional claim language, as neither IPR nor reexamination can consider eligibility grounds.

The Final IPR Rule and Four Pending Petitions Will Set the Terms for 2027

The USPTO's final rule revising IPR institution practice, Revision to Rules of Practice Before the Patent Trial and Appeal Board (RIN 0651-AD89), has been pending at the White House Office of Information and Regulatory Affairs (OIRA), the office that reviews significant agency rules before publication, since July 22, 2026, according to the OIRA review record. The proposed version, 90 Fed. Reg. 48335 (Oct. 17, 2025), would require each petitioner to stipulate not to raise anticipation or obviousness grounds against the challenged patent in any other proceeding, and would bar institution where a court or the Board has already upheld a challenged claim or where a parallel proceeding is likely to decide validity first. As of now, the final rule has not been published.

The Supreme Court has four pending petitions on institution authority and reviewability: Intel, Tesla, Kahoot!, and FedEx. A formal USPTO announcement returning merits institution decisions to Board panels would also change who decides whether a petition shows a reasonable likelihood that the petitioner would prevail on at least one challenged claim, while leaving discretionary denials, including settled expectations, with the Director.

Looking Ahead

The Supreme Court's October 19 denial leaves the settled-expectations framework in place and the question of the framework's lawfulness undecided. The Federal Circuit has held the Director's institution decisions insulated from review in the postures presented so far, except for colorable constitutional claims, and the remaining petitions give the Supreme Court a further opportunity to decide whether any court may review the Director's institution decisions.

The more lasting effect of settled expectations may be the resulting shift in which proceeding patent challenges are raised. An older AI patent the Office declines to review in an IPR remains open to reexamination based on the same publications, before an examiner with no patent-age restriction to apply, on a request the patent owner has only 30 days to answer, and sometimes from a requester the patent owner cannot identify. For AI patent owners, settled expectations may change where an older patent is challenged rather than whether it is challenged. In USPTO data through September 30, 2025, only 22.2% of reexamination certificates confirmed all claims, leaving nearly 4 in 5 reexamined patents with changed claims or with all requested claims canceled. Outcomes for the current surge of requests will become clearer as those reexaminations reach final decisions.