Post-Grant Challenges Recap
Post-grant proceedings at the Patent Trial and Appeal Board (PTAB) have experienced a seismic shift since March 2025 when United States Patent and Trademark Office (USPTO) Acting Director Coke Morgan Stewart published a memorandum fundamentally changing how institution decisions for inter partes review (IPR) and post-grant review (PGR) are made. The memorandum established a bifurcated process including a formal track for the Director to first determine, in consultation with at least three PTAB judges, whether or not the Director should exercise their discretion and deny institution for each IPR and PGR.[1] Only if the Director decides not to discretionarily deny the petition, does the case proceed to the PTAB for consideration of the merits. Prior to this policy change, standard practice delegated institution authority to the PTAB’s three-judge panel of Administrative Patent Judges (APJs).

In September 2025 USPTO Director Squires took office, ended this bifurcated process, and consolidated the Director’s authority over all aspects of institution decisions. In a memorandum issued October 2025, Director Squires formally removed delegation of institution authority from the PTAB for IPR and PGR proceedings, and placed institution decisions solely in the hands of the Director.[2] The Director continues to weigh traditional discretionary factors such timing of parallel proceedings, but in a critical change now also considers additional factors such as settled expectations (patent age), petitioner filing delays, and U.S. manufacturing of accused products when determining whether discretionary denial is appropriate. After considering discretionary factors, the Director now makes the merit-based institution determination and issues a concise summary notice. Prior to this latest change, the PTAB three-judge panel made all merit-based institution determinations and issued a decision detailing their rationale for each petition.

The October 2025 memorandum was accompanied by an open letter from the USPTO outlining the statutory support for consolidating Director review, explaining that the Director’s authority to make institution decisions stems from 35 U.S.C. § 314(a) as codified by the America Invents Act (AIA).[3] Director Squires noted that when passing the AIA, Congress made plain that “[t]he Director may not authorize an inter partes review to be instituted unless the Director determines that… there is a reasonable likelihood that the petitioner would prevail with respect to at least 1 of the claims challenged.”[4] Further, § 314(b) states the "Director shall determine whether to institute an inter partes review.”[5]

The memorandum and letter coincided with a Notice of Proposed Rulemaking (“NPRM”) in which the USPTO laid out the rationale for this change. The NPRM noted the “AIA allocated expansive authority to the USPTO to prescribe regulations governing AIA proceedings, including IPRs,” citing 35 U.S.C. § 316(a).[6] For example, 35 U.S.C. § 316(a)(4) instructs the Director to govern the relationship between IPRs and other proceedings, including parallel district court actions and ex parte reexamination (EPR). The NPRM spells out that “[s]erial and parallel validity challenges remain a significant problem for the patent system,” finding more than half of all IPR petitions are one of multiple petitions against the same patent, and that over 80% of IPRs have co-pending district court litigation.[7] However, during passage of the AIA, Congress “recognize[d] the importance of quiet title to patent owners to ensure continued investment resources” and did not want “repeated litigation and administrative attacks on the validity of a patent.”[8] The USPTO is openly concerned about the rights of patent owners, mirroring concerns previously raised by the AIA’s Senate sponsors in 2011 who feared unlimited challenges “would limit the ability of inventors to attract capital investment and…bring [products] to the marketplace.”[9] While the October 2025 NPRM has not resulted in a final rule, the USPTO has established that existing rules give the Director “broad discretion to decide not to proceed with institution, even if a petition satisfies the minimum statutory threshold for instituting an IPR.”[10] In the latest development, Director Squires indicated during a September 2026 oversight hearing before the Senate Judiciary Subcommittee on Intellectual Property that APJs at the PTAB may soon resume making institution decisions on the merits.[11]

The Statistics Don’t Lie
These changes to post-grant proceedings reset the landscape over the past 18 months. Patent challengers have been deterred by these stricter procedures, and as a result sought alternatives to IPR and PGR proceedings. By the first half of 2026, many validity challenges migrated from IPRs administered by the PTAB, to EPRs administered by the Central Reexamination Unit (CRU). In Q1 2026, IPR petitions fell 64% to a historic low of 131 as a result of the policy shift towards discretionarily denying PTAB trials.[12] By Q2, IPR petitions dropped to 57, an all-time quarterly low; while EPR requests reached 336, an all-time quarterly high.[13] Prior to this policy change, IPRs represented 73% of post-grant filings, and EPRs just 24%. Since the policy change, the statistics have nearly inverted - EPRs represented 75% of post-grant filings in the first half of 2026, bringing EPR practice to the forefront for practitioners, as well as inviting extra scrutiny from the Office.

Estoppel Considerations for Parallel IPR and EPR Proceedings
Despite their decline in filings, patent challengers are still pursuing IPRs, though at times filing EPRs in parallel. Practitioners should be aware of timing considerations, the effect of 35 U.S.C. § 315(e)(1) estoppel, and potential new rules proposed in July 2026 requiring EPR applicants to disclose their identity to the USPTO.

Since the AIA took effect, there has been ambiguity regarding when IPR estoppel under § 315(e)(1) attaches. When the AIA was signed into law, Congress acknowledged the need to protect patent owners from repeat challenges to the same claims at the USPTO, and created § 315(e)(1) to address this. § 315(e)(1) states that the petitioner or real party in interest (RPI) of an IPR that results in a final written decision “may not request or maintain a proceeding before the Office with respect to that claim on any ground that the petitioner raised or reasonably could have raised” during the IPR.[14] In short, once an IPR final written decision is issued, statutory estoppel before the Office is triggered.

In the case of In Re:Gesture Technology Partners, the organization Unified Patents first filed an IPR, followed by a different entity (who was a member of Unified Patents) filing an EPR against the same patent.[15] While the IPR was ongoing, the follow-on EPR request was instituted (i.e., ordered). The IPR culminated in a final written decision invalidating most of Gesture’s claims. The EPR was then later decided invalidating all of Gesture’s remaining claims.

Gesture appealed the EPR, arguing the USPTO should have terminated the EPR once the IPR reached final written decision.  In particular, since the follow-on EPR was filed by a member of Unified Patents, they are thus a real a party in interest, and 35 U.S.C. § 315(e)(1) applies barring the EPR petitioner from “maintain[ing] a proceeding before the Office” against the same claims. The Federal Circuit disagreed, based on the fact that the EPR requester is not involved in the EPR proceeding once an EPR is instituted, and thus does not maintain the EPR. An EPR requester’s involvement ends after filing the petition and optional reply. The Court found the “petitioner requests a reexamination…but the petitioner does not maintain the proceeding. Rather, the Patent Office does...We thus conclude that the estoppel provision of 35 U.S.C. § 315(e)(1) is inapplicable against the Patent Office to ongoing ex parte reexamination proceedings.” Therefore, estoppel applies to the petitioner and its privies, but not to the USPTO; and there is no statutory basis to terminate an EPR once underway. This decision increases the potency of follow-on EPRs, as IPR estoppel will not halt reexamination once it has begun.

On the other hand, in HID v. CPC Patent Technologies, the USPTO clarified that an IPR final written decision received after the EPR is filed, but before it is instituted, indeed results in EPR estoppel under § 315(e)(1).[16] Note, the USPTO has three months from the filing of an EPR request to make an institution decision based on any substantial new questions of patentability (SNQP).[17] The EPR institution rate is currently approximately 95%.[18]

Proposed Rule Changes to End Anonymous EPR Requests
This shift to EPRs is leading to additional changes. The USPTO in July 2026 published another NPRM seeking to end anonymous EPR filings by requiring applicants to disclose their identity to the Office.[19] EPR requests can currently be made anonymously via a registered practitioner. Practically speaking, for the USPTO to determine whether § 315(e)(1) estoppel applies to an EPR against the same claims previously subject to an IPR, all real parties in interest requesting the EPR must be known to the Office. However, 35 U.S.C. § 302 states “[a]ny person at any time may file a request for reexamination by the Office,” and 35 U.S.C. § 301(e) allows any person citing prior art to the Office (such as an EPR petitioner) to request their identity “be excluded from the patent file and kept confidential.” 37 CFR 1.501(d) further states “[i]f the person making the submission wishes his or her identity to be excluded from the patent file and kept confidential, the submission papers must be submitted anonymously without any identification of the person making the submission.” The confidentiality of an EPR requester has always extended to the USPTO itself. While IPR petitioners must identify all real parties in interest,[20] EPR requesters do not — making it impossible for the USPTO to enforce § 315(e)(1), which requires analysis of IPR and EPR petitioners or real parties in interest.

The EPR confidentiality rule was inserted by Congress because “[w]ithout the confidentiality provision, competitors of a patent owner might be reluctant to cite prior art to the [USPTO].”[21] However, to ensure the AIA’s estoppel provisions were not circumvented, every EPR requester since 2012 has been required to self-certify they are not estopped under § 315(e) — a certification subject to the Office's truthfulness and improper-purpose obligations, backed by criminal penalties for knowingly false statements.[22]

While the USPTO notes the importance of confidentiality to EPR requesters, the new rules would still allow keeping the requester's identity confidential from the public, but not from the Office. Therefore, even if the patent owner and public do not know who is behind the request, the USPTO itself would.

The July 2026 NPRM generated comments from industry, practitioners, and organizations including the American Intellectual Property Law Association (AIPLA), the Intellectual Property Owners Association (IPO), and the PTAB Bar Association. The majority of comments were critical of the proposed rule change. For example, the IPO concluded that the scope of the proposed rule is broader than necessary, since it would apply to all EPRs, regardless of whether or not there was a parallel IPR.[23] The IPO noted that 2026 USPTO data indicated only a small percentage of EPR requests involve patents previously challenged by an IPR, therefore a “more targeted disclosure trigger” would better align the Office’s proposed universal solution with its targeted estoppel concerns.

The USPTO acknowledged that previous attempts at requiring identification of all real parties in interest were scrapped due to concerns of “a chilling effect” on EPR requests.[24] For example, anonymity for third party EPR requesters can avoid retaliatory litigation, protect business plans, and head off economic fallout when opposing parties are competitors, customers, suppliers, licensing partners, or industry collaborators.

Lastly, the administration of the disclosure obligation would be challenging, because “real party in interest” is not defined by  35 U.S.C, but rather treated as a common-law term by the Federal Circuit.[25] As raised by the IPO, “[i]dentifying all real parties in interest can require fact-intensive analysis of corporate affiliations, supplier and customer relationships, indemnification obligations.” The proposed rule could prove burdensome in some cases.

Practical Considerations
IPR petitioners considering a co-pending EPR request should recognize the two tracks may reach different endpoints at different times. Petitioners should time follow-on EPRs relative to the stage of the parallel IPR proceeding, being especially careful to both file the EPR and have the request instituted before the PTAB issues a final written decision. HID clarified that simply filing an EPR request is not sufficient to lock in the right to the parallel proceeding. However, once the EPR is instituted, even a later final written decision on the same claims will not terminate reexamination. Practitioners should consider this timing early on in their overall strategy. Patent owners should also be aware that surviving IPR claims can be reviewed again during reexamination.

As to settlement, patent owners and petitioners should now reassess settlement timing.  For example, during parallel IPR and EPR proceedings, a patent owner who holds out for a final written decision will create stronger estoppel protections, because once the final written decision issues, both new EPR requests and existing requests not yet instituted will be barred under § 315(e)(1). Petitioners who settle before IPR final written decision still have the option to pursue future EPR requests, though best practice would be to draft the settlement so the challenged patent never has to be dealt with again.

Regarding the July 2026 NPRM, if adopted, practitioners would become burdened with establishing the RPI before filing an EPR. Determining RPI is fact specific and could be time consuming to determine in certain cases. While patent owners may welcome this rule for bringing transparency, if passed, EPR requesters should make sure to determine RPI early. Finally, practitioners should be aware there are concerns about the identity of the requesting party being revealed by the USPTO in response to subpoenas or requests for information under the Freedom of Information Act (FOIA), and the potential chilling effects such disclosure may cause.[26]

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