The Federal Circuit recently affirmed a Patent Trial and Appeal Board decision finding claims that had been subject to an ex parte reexamination unpatentable. As a threshold issue, the court held that IPR estoppel under 35 USC § 315(e)(1) does not apply to ongoing ex parte reexaminations. Accordingly, the Patent Office did not err in continuing the reexamination after issuing final written decisions in co-pending IPRs.
The patent covered methods and an apparatus for computer-based object sensing. After issuance, a third party requested ex parte reexamination of all claims, which the Patent Office granted. Two IPRs were also filed against the patent. The party that requested the reexamination was a member of the organization that filed one of the IPRs. The board in due course issued final written decisions in the IPRs finding all but two claims unpatentable.
Following those decisions, the patentee petitioned the Patent Office to terminate the reexamination, arguing that the IPR estoppel provision of § 315(e)(1) prevents the third-party requester from maintaining the proceeding. The Patent Office disagreed, and in the reexamination invalidated all claims—including the two that survived IPR review. The board affirmed and the patentee appealed.
On appeal, the patentee challenged the Patent Office’s decision to not terminate the reexamination pursuant to § 315(e)(1) estoppel once the IPR decisions issued. According to the patentee, the reexamination should have been terminated because the third-party requester was a member of the organization that had filed one of the IPRs, and once the final written decision in the IPR issued, it could not “maintain a proceeding” at the Patent Office challenging the same patent on any ground it could have raised in the IPR. The patentee further argued that because an ex parte reexamination is a “proceeding before the Office,” § 315(e)(1) estoppel applies.
The Federal Circuit disagreed. In so doing, the court focused on the statute’s language which provides that “[t]he petitioner in an [IPR] . . . may not request or maintain a proceeding before the Office” on certain grounds after the IPR decision issues. The court clarified that while a petitioner can “request” an ex parte reexam, its role ends after the initial stage. At that point the Patent Office—not the requester—“maintains” the reexam. Therefore, § 315(e)(1) estoppel does not apply to ongoing ex parte reexaminations and the Office did not err by denying the patentee’s request to terminate the reexam in this case.
Practice Tip: When pursuing both IPR and ex parte reexamination, the timing of the reexamination request may be critical. For a patent challenger, filing a reexam request early may ensure initiation of the reexamination before any IPR final written decision. Once initiated, the reexamination is maintained by the Patent Office, and estoppel under § 315(e)(1) may be inapplicable to effect termination of the reexamination.
In re Gesture Tech. Partners, LLC, No. 2025-1075 (Fed. Cir. Dec. 1, 2025)