IPR Petitions Collapse to Historic Low — Ex Parte Reexamination Overtakes IPR for First Time Since AIA

Filings for inter partes review (IPR) at the US Patent and Trademark Office (USPTO) have collapsed to a historic low, with only 11 IPR petitions filed in the four-week window ending May 2, 2026 — the lowest 4-week period since the system launched in September 2012. Over the same period, ex parte reexamination requests have surged, peaking above 130 in a 28-day window and overtaking IPR for the first time as the leading post-grant validity tool by petition count. The data was compiled by Patently-O’s Professor Dennis Crouch, who described the shift as a “decimation” of the IPR system.

From early 2021 through mid-2025, IPR petitions cycled in a stable band of roughly 80 to 130 filings per 28-day window. Filings began dropping sharply in late 2025 and have now fallen into single digits. Over the same period, ex parte reexamination has grown to the point where it leads at the petition stage.

The cumulative weight of discretionary denials

The collapse in IPR filings traces directly to the USPTO’s escalating use of discretionary-denial doctrines. The NHK-Fintiv framework defers IPR institution when parallel district-court litigation is advancing toward trial; the “settled expectations” doctrine limits IPR challenges to older patents on which owners have come to rely; and a March 11, 2026 memorandum from USPTO Director John Squires added explicit discretionary considerations tied to US manufacturing and small-business status of the petitioner.

The Squires memo directs Board panels to weigh whether the accused products in parallel litigation are manufactured in the United States, whether the patent owner makes competing US products, and whether the petitioner is a small business that has been sued for infringement. Each of those factors tilts the discretionary calculus toward denying institution.

The shift to ex parte reexamination and its tradeoffs

While ex parte reexamination has overtaken IPR by petition count, the two proceedings are procedurally very different. IPR is an inter partes contest in which patent owner and petitioner appear before the Patent Trial and Appeal Board (PTAB) and litigate validity to a final written decision. Ex parte reexamination proceeds primarily between the examiner and the patent owner; the third-party requester is essentially an observer once the request is filed.

Giving up the participatory rights of IPR is nonetheless a rational tradeoff for petitioners trying to avoid the discretionary-denial trap. According to USPTO data, the majority of recent ex parte reexamination requests are third-party filings — confirming that the channel is absorbing challenges that would otherwise have gone to PTAB. Critics warn, however, that without an adversarial counterparty, patent owners are better positioned to amend claims through reexamination and emerge intact.

Implications for Big Tech and patent litigation

The shrinkage of IPR forces strategic recalibration on the technology defendants who built their patent-defense playbooks around it. Apple, Google, Intel, Cisco, and Edwards Lifesciences challenged the USPTO’s discretionary-denial regime at the Federal Circuit in February 2026 and lost. Google in early May 2026 filed a certiorari petition asking the Supreme Court to resolve whether the “settled expectations” doctrine can lawfully bar IPR challenges to older patents.

Outside the courts, challengers are turning to a fragmented set of substitutes: ex parte reexamination, invalidity defenses in district court, ITC proceedings, and arguments preserved for the PTAB appeal stage. None of these replicates the speed, cost-efficiency, and adversarial structure of IPR, and litigants are bearing higher expected costs as a result.

A crossroads for the AIA framework

The America Invents Act of 2011 created IPR to improve patent quality and curb low-merit infringement suits. Thirteen years later, the flagship post-grant tool of the AIA is operating at a fraction of its historical volume. The USPTO published a proposed rule in October 2025 moving toward a “one-and-done” model in which patents that survive any initial validity challenge become effectively immune from subsequent IPR.

Congress, industry, patent owners, and technology defendants are likely to revisit the political economy of the system. The Federal Circuit’s pending appeals, the Supreme Court’s response to Google’s settled-expectations petition, and the final form of the USPTO’s IPR rule rewrite will, over the next several months, reshape the framework for challenging US patent validity.

Practical implications

For patent owners, the contraction of IPR is short-term good news, but they will increasingly need to defend on multiple fronts: ex parte reexamination amendments, district-court invalidity, and the unsettled Federal Circuit jurisprudence around discretionary denial. Defendants, in turn, need to rethink playbooks that took IPR institution for granted — re-evaluating ex parte reexamination’s tradeoffs, the timing of district-court invalidity contentions, and ITC strategy. The US patent-challenge market is undergoing its first major realignment since the AIA went into effect.