PTAB Petition Filings Collapse 64% in Q1 2026—Discretionary Denials Drive Historic Low

PTAB petition filings fell 64.2% year-over-year to a historic low of 131 petitions in the first quarter of 2026, according to the Patent Dispute Report: Q1 2026, published by Unified Patents on April 14, 2026. Inter partes review (IPR) petitions led the decline, plummeting 66.3% compared to the same period in 2025—the lowest quarterly IPR count since the America Invents Act introduced the proceeding over a decade ago.

The driving force behind this collapse is the surge in discretionary denials that began in 2025 and continued into 2026. The USPTO Patent Trial and Appeal Board has increasingly exercised its discretion to decline petitions, particularly in cases where parallel district court litigation is already pending or where petitions fail to satisfy procedural standards. This elevated denial rate has created a strong deterrent effect, causing prospective petitioners to reconsider the cost-benefit calculus of filing IPR challenges.

PTAB IPR Decline

USPTO Pre-Order Procedure

As IPR filings contracted, patent challengers shifted to an older mechanism: ex parte reexamination. Q1 2026 recorded the second-highest volume of ex parte reexamination requests in history, trailing only the all-time high set in Q4 2025. Reexamination requests surged 157.1% compared to Q1 2025. Post-grant review (PGR) petitions also declined, falling 26.3% year-over-year. Meanwhile, district court patent filings decreased 21.6% compared to Q1 2025.

The geographic concentration of patent litigation in Texas remained pronounced. More than 37% of all patent cases were filed in the Eastern or Western District of Texas. For NPE cases specifically, that concentration exceeded 57%, with the E.D. Tex. and W.D. Tex. continuing to attract filings from non-practicing entities targeting defendants on a national scale.

Non-practicing entities dominated patent litigation activity in Q1 2026. NPEs filed 53.2% of district court patent cases overall; in the high-tech sector—covering software, hardware, and networking technologies—NPEs accounted for 90.3% of patent litigation. Eight of the top ten district court plaintiffs in Q1 2026 were NPEs. At the PTAB, Bulletproof Property Management LLC, an NPE, ranked as the top patent owner, with six of the top ten PTAB patent owners being NPEs. Apple was the leading non-Schedule A defendant in district court.

Institution rates at the PTAB have shifted significantly in ways that disadvantage NPE patent owners. In Q1 2026, the institution rate for petitions against NPE-owned patents was 24.6%—more than 15 percentage points below the institution rate for petitions against operating companies. In Q4 2025, the institution rate stood at 33.6% against NPEs and 53.2% against operating companies. Both figures have declined substantially year-over-year, but the gap has widened, a trend the report attributes to the higher rate of discretionary denials applied to NPE-owned patents. Google ranked as the top PTAB petitioner in Q1 2026.

The structural shift visible in Q1 2026 data carries practical implications for IP practitioners. First, the rising unpredictability of IPR institution decisions—driven by expanded discretionary denial criteria—has elevated the threshold for filing and increased the importance of early case assessment. Second, the migration toward ex parte reexamination reflects a search for alternative channels to challenge patent validity, though reexamination imposes different procedural dynamics and places the challenger in a less adversarial posture relative to the patent owner. Third, the simultaneous decline in district court filings suggests that overall patent dispute activity is contracting rather than simply rerouting—a development that may reflect broader uncertainties in the U.S. patent enforcement environment.

Unified Patents compiled the Q1 2026 report from data covering all district court, PTAB, reexamination, and UPC cases filed between January 1, 2012 and March 31, 2026. The methodology excludes mistaken, duplicative, or change-of-venue filings.