Key Takeaways from Session 10: Navigating the New PTAB Playing Field

Changes in PTAB practice are reshaping how companies approach patent challenges and portfolio strategy. As AIA petition filings decline and ex parte reexamination requests rise, companies are taking a closer look at alternative pathways for managing litigation, licensing, and patent portfolio risk.

In the latest installment of Sterne Kessler’s Navigating the New PTAB Playing Field webinar series, Directors Jason Eisenberg, David Holman, Ph.D., and Jacqueline W. Bonilla, Ph.D. explore the latest developments and procedures in both AIA and ex parte reexamination proceedings. Key highlights include:

1. Ex Parte Reexamination Has Reemerged as a Major Strategic Forum: For years, AIA petitions were filed at a relatively steady monthly pace (about 100-110 per month), while ex parte reexamination requests occupied a smaller (about 40 per month) but consistent role. Beginning in the second half of 2025, however, AIA petition filings decreased, while reexamination requests increased. In fact, today, AIA petition filings have dropped from about 1300 in 2024 to what is projected to be about 400 petitions filed in 2026, i.e., ~70% drop. By contrast, reexamination request filings are on track in 2026 to be 2-3 times the numbers seen each year over the last 10-12 years. Moreover, the grant rate of reexamination requests remains high at ~90%, while the institution rates of AIA reviews have been ~35% for all of 2026 so far (although institution rates have been higher in recent months, e.g., ~60% since June 2026). Organizations assessing patent risk should consider both forums early, because each presents different thresholds, consequences, and strategic uses.
2. Estoppel, Settlement, and Anonymity Create Material Differences: Reexamination does not create requester estoppel from the proceeding itself. In addition, a party may file a request anonymously (at least for now—rulemaking is pending on this issue). And, as a general matter, a requester and/or patent owner cannot stop an ordered reexamination from proceeding, e.g., upon settlement of the parties. These features are opposite from AIA proceedings that create broad estoppels and can be stopped by settlement, which can materially affect leverage and risk planning.
3. The New Patent-Owner Pre-Order Paper Front-Loads the Dispute: Patent owners may now address whether a substantial new question of patentability exists before reexamination is ordered. Requesters should build a complete record at filing, while patent owners should monitor new requests closely and prepare substantive threshold arguments. Although, early empirical data does not demonstrate patent owners are routinely taking advantage of Pre-Order Papers or that, when they do, the Pre-Order Paper is successful in reducing grant rates for reexaminations.
4. Prior USPTO Proceedings Must Be Addressed with Precision: Section 325(d) is receiving greater attention in reexamination in a small sampling of cases where the requests were denied almost summarily when merely duplicating a failed AIA proceeding. Despite the small sample size, it is imperative for requesters to use new references, combinations, and/or arguments to distinguish a request from prior proceedings, as requests presenting the exact same art and grounds have faced denial in recent months. Indeed, requests for reexamination have been denied under § 325(d) over a prior IPR petition asserting the same art and arguments, even though the IPR petition was discretionarily denied with no analysis on its merits.
5. Commercial Outcomes Matter More Than All-or-Nothing Metrics: A reexamination and an AIA proceeding can create value for a challenger even when not every claim is canceled. Amended claims and mixed outcomes may change infringement positions, past-damages exposure, licensing leverage, or the strength of a portfolio.