As IPR institution becomes less predictable, multinational defendants should consider whether a corresponding European patent offers another path to challenge the patent owner’s global enforcement position.

The Ptab Bottleneck

For more than a decade, a company sued on or threatened by a U.S. patent could treat inter partes review as a central defensive option. Recently that assumption has become less reliable. Official USPTO data through July 31, 2026, show an FY2026 year-to-date institution rate of 39% by petition, down from 68% in FY2024. The underlying split is substantial: 58% of petitions receiving a Director-level discretionary determination were denied, while 76% of matters reaching merits or other statutory review were granted.

Under the current process, the parties brief discretionary considerations separately from the merits and other statutory considerations. Effective October 20, 2025, the Director determines whether to institute after reviewing discretionary considerations, the merits, and non-discretionary considerations in consultation with at least three PTAB judges; the Director may refer the institution decision to one or more Board members where appropriate. If review is instituted, the proceeding is referred to the PTAB to conduct the trial. This process makes the Director the institution gatekeeper, with the consequence that the question becomes not only whether the invalidity case is strong, but whether it will be heard.

The Office’s March 2025 process separates discretionary briefing from the merits, and later guidance added considerations such as domestic manufacturing, U.S. investment, and small-business status. An April 2026 ex parte reexamination procedure also permits patent-owner input before the substantial-new-question determination, and a July 2026 proposed rule would require third-party requesters to identify all real parties in interest. Those developments do not establish a comparable collapse in reexamination orders, but they reinforce the need to evaluate alternative forums early.

A different patent, but a real second front

One possible response is a standalone revocation action before the Unified Patent Court against a European patent corresponding to the asserted U.S. patent. The strategy begins with four questions: Is there a granted European family member? Is it within UPC jurisdiction and not validly opted out? Is the proposed claimant “concerned by” the patent under Article 47(6)? And, most importantly, do the European and U.S. claims actually correspond?

As for standing, the claimant-status threshold for a third-party revocation action was further defined in LS9 GmbH v. Bellissa HAAS GmbH, where the Milan Central Division held at first instance that legal persons generally satisfy it even without activity in the relevant industry, suggesting—subject to further appellate development —that a corporate challenger need not show existing European sales or a specific infringement threat. The decision is in German because central-division proceedings use the patent’s language of grant; footnote 3 links the decision and a detailed English summary. 

The UPC can revoke a patent throughout the participating states in which it has effect, and revocation operates retroactively. It may consider EPC grounds—including lack of novelty or inventive step, insufficiency, added matter, and certain entitlement or post-amendment scope defects—that are broader than an IPR’s Sections 102 and 103 grounds based on patents and printed publications. A UPC revocation action has no PTAB-style policy-based institution gate, no Section 315(b) one-year service bar, and does not itself trigger Section 315(e) IPR estoppel. 

A UPC judgment, however, cannot revoke the U.S. patent, bind a U.S. district court, the ITC, the PTAB, or the USPTO, or automatically produce issue preclusion in the United States.

... Continue reading to discover how UPC revocation actions may influence global patent disputes and create leverage in parallel U.S. proceedings...