Overlooked, But Powerful: Ex Parte Reexamination And Inter Partes Review Combination

In In Re Gesture Technology Partners, LLC, Case No. 2025-1075 (Fed. Cir. December 1, 2025) ("Gesture"), the Federal Circuit reinforced the power of ex parte reexaminations as powerful tools for invalidating active and expired patents in combination with inter partes review ("IPR") by holding that the estoppel provision of 35 U.S.C. § 315(e)(1) does not apply to ongoing ex parte reexaminations because petitioners are not involved in the reexamination proceeding; and that the Patent Office has jurisdiction over ex parte reexaminations concerning expired patents because patent owners maintain some rights after the patent expires, which can create a live case or controversy that can be resolved by an ex parte reexamination.

In Gesture, the patent owner appealed an ex parte reexamination decision of the U.S. Patent and Trademark Office Patent Trial and Appeal Board ("the Board") affirming the unpatentability of claims 1-30 of U.S. Patent 7,933,431 ("the '431 patent") as either anticipated or obvious. The ex parte reexamination at issue was requested while two IPRs seeking to invalidate all claims of the '431 patent were pending. One of the two IPRs was petitioned by Unified Patents LLC, an organization of which the ex parte requester is a member. The Board issued a final written decision in each IPR invaliding all but two claims of the '431 patent. The Federal Circuit has since affirmed both IPR decisions.

Following the final decisions in both IPRs, Gesture petitioned to terminate the pending ex parte reexamination, asserting that, as a member to the Unified Patents IPR, the requester was estopped under 35 U.S.C. § 315(e)(1) from maintaining the pending reexamination proceeding at the Patent Office. The Patent Office denied the petition and concluded that the estoppel provision of § 315(e)(1) does not apply to ongoing ex parte reexaminations. Subsequently, a final office action was issued by an examiner in the ex parte reexamination rejecting the two remaining uncanceled claims of the '431 patent as anticipated by a prior art, and the Board affirmed the rejection and invalidated all claims of the'431 patent.

On appeal, Gesture argued that the Patent Office erred in determining that the estoppel provision of 35 U.S.C. § 315(e)(1) does not apply to pending ex parte reexamination proceedings. Gesture further argued that the Patent Office has no jurisdiction over the '431 patent because the '431 patent is expired.

35 U.S.C. § 315(e)(1) Is Inapplicable to Ongoing Ex Parte Reexamination Proceedings

The Federal Circuit held that "the estoppel provision of 35 U.S.C. § 315(e)(1) is inapplicable against the Patent Office to ongoing ex parte reexamination proceedings." The Federal Circuit clarified that a petitioner requests an ex parte reexamination but does not maintain the proceeding. The Patent Office does. Moreover, other than the optional reply provided by 35 U.S.C. § 304, the ex parte reexamination statute does not provide for any involvement of the requester in the reexamination proceeding.

Since the promulgation of the Leahy-Smith America Invents Act, the Patent Office's guidance on § 315(e)(1) and § 325(e)(1) has been that the estoppel provisions do not apply to pending reexamination proceedings. MPEP § 2210. This guidance has now been converted into law by the Federal Circuit.

However, the Patent Office maintains that the estoppel provisions of § 315(e) and § 325(e) "only prohibit the filing of a subsequent request for ex parte reexamination, once estoppel attaches." MPEP § 2210. So far, the majority of ex parte reexamination proceedings have been terminated due to improper certification under 37 CFR 1.510(b)(6). As such, petitioners may avoid making improper 1.510(b)(6) certification by filing an ex parte reexamination before filing an IPR, in conjunction with the IPR, or any time prior to the issuance of an IPR final written decision. In addition, petitioners may consider pursuing different claims in the IPR and the ex parte reexamination.

The Patent Office Has Jurisdiction Over Ex Parte Reexaminations Concerning Expired Patents

The Federal Circuit also concluded that, similar to IPRs, "the Board has jurisdiction over ex parte reexaminations concerning expired patents." The Federal Circuit stated that the reasoning it applied for IPRs in Apple Inc. v. Gesture Tech. Partners, LLC, 127 F.4th 364, 368-69 (Fed. Cir. 2025), cert. denied, No. 24-1280 (U.S. Nov. 17, 2025), where it confirmed that the Board has jurisdiction over IPRs concerning expired patents, also applies for ex parte reexaminations. Specifically, "a patent owner maintains some rights after the patent expires, including the right to sue for past damages, which can create a live case or controversy that can be resolved by an ex parte reexamination."

Ex Parte Reexamination and IPR Combination

IPR petitioners should consider leveraging ex parte reexaminations in combination with an IPR to enhance the chances of invalidating all claims of a patent. An ex parte reexamination is a passive way of getting at the same outcome as an IPR and can have synergistic invalidating effects as shown in this case. Petitioners may also consider filing an ex parte reexamination in lieu of seeking a joinder on an existing IPR. An ex parte reexamination has several advantages:

1) The estoppel provision of 35 U.S.C. § 315(e)(1) does not apply to a pending ex parte reexamination;

2) Expired patents can be reexamined;

3) Theex partereexamination can be filed anonymously;

4) Theex partereexamination is limited to two office actions;

5) The requester does not maintain the proceeding, but can optionally reply to a patent owner preliminary statement;

6) The ex parte reexamination does not require discovery or deposition because the Patent Office maintains the proceeding;

7) There are no word or page limits;

8) The threshold for granting a request for ex parte reexamination is determining the presence of a "substantial new question of patentability" (SNQ); and

9) The proceeding is not subject to a discretionary denial under 35 U.S.C. § 314.

As the landscape of post-grant proceedings continues to evolve, understanding how to strategically combine tools like ex parte reexaminations and IPRs can make a decisive difference in protecting — or challenging — valuable IP assets.

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