PTAB challenges

Proceedings overview

A single AIA trial proceeding has been filed against US patent 11905896, IPR2025-01228. This Inter Partes Review (IPR) was terminated at the pre-institution stage by a discretionary denial. This means the patent has not been subjected to a merits review at the PTAB, and all claims remain untested by an IPR challenge. For a defendant, this indicates that the patent has not been "hardened" by surviving IPR, but also that an IPR challenge on similar grounds might face the same discretionary denial.

IPR2025-01228 — Generac Power Systems, Inc. et al. v. Champion Power Equipment Inc.

• Type: Inter Partes Review
• Filed: 2025-07-11
• Status: Discretionary Denial – The Director of the USPTO (or a delegated authority) declined to institute the Inter Partes Review, without addressing the merits of the patentability challenge. This decision is made based on various discretionary factors before a full trial proceeds. The "last modified" date of 2026-03-05 likely reflects the date of this denial.
• Judge panel: The decision for discretionary denial is made by the Director of the USPTO or a delegated Deputy Director, rather than a full PTAB panel for merits review. While specific names for this IPR's denial are not publicly detailed in the provided information, John A. Squires was mentioned as USPTO Director around November 2025, and Coke Morgan Stewart as Acting Director earlier in 2025, both involved in discretionary denial policy.
• Petition grounds: The specific claims challenged, the prior art asserted, and the statutory bases (§ 102 / § 103 / § 112) for IPR2025-01228 are not explicitly provided in the available information.
• Institution decision: The petition was denied institution on discretionary grounds, likely on or around 2026-03-05. The PTAB has recently implemented a two-step decision process where discretionary considerations are addressed first. Common reasons for discretionary denial include the existence of parallel district court litigation, the timing of the petition relative to the patent's issuance (e.g., "settled expectations"), or inconsistent claim construction positions taken by the petitioner in different forums. Notably, in related IPRs (IPR2025-00805 and IPR2025-00951) concerning a different patent but involving Generac Power Systems, Inc. and Champion Power Equipment, Inc., institution was denied due to the petitioner's inconsistent claim construction positions between district court and PTAB proceedings. It is plausible that IPR2025-01228 was denied for similar reasons, though the specific reasoning for this particular IPR is not stated.
• Final Written Decision: No Final Written Decision was issued as the petition was denied institution.
• Settlement / termination: There is no indication in the provided information that the proceeding was terminated due to settlement.
• Appeal: Appeals of PTAB decisions denying institution are generally barred from judicial review by 35 U.S.C. § 314(d).
• Defensive value: This discretionary denial means that the claims of US11905896B2 have not been challenged on their merits at the PTAB. The patent owner successfully prevented a trial from commencing. A defendant considering an IPR challenge would need to carefully evaluate the reasons for this discretionary denial to avoid a similar outcome, especially if parallel litigation exists or if there are any inconsistencies in their legal positions.

Strategic summary

All claims of US11905896 remain UNTESTED by a merits review at the PTAB, as the sole IPR proceeding filed against it (IPR2025-01228) was denied institution on discretionary grounds. This means no claims were canceled or sustained through an IPR trial.

The estoppel landscape for IPR2025-01228 is limited. Since institution was denied, the petitioner (Generac Power Systems, Inc. et al.) and its privies would be estopped under 35 U.S.C. § 315(e)(1) from challenging the claims in a subsequent PTAB proceeding only on grounds that were actually raised and addressed in the decision. However, because the denial was discretionary and did not reach the merits, the specific grounds of unpatentability were not adjudicated. More significantly, a denial of institution does not typically trigger the broader estoppel of § 315(e)(2), which applies to all grounds that reasonably could have been raised in the IPR, because no trial was instituted. Therefore, many prior-art grounds could still be available for a different party or even potentially for the same petitioner if circumstances change and a new petition overcomes the discretionary hurdles.

Regarding pattern signals, the filing of IPR2025-01228 by Generac Power Systems, Inc. et al. indicates that the patent is being asserted or is of interest to this entity, consistent with Generac's involvement in district court litigation against Champion Power Equipment, Inc. concerning multi-fuel generators. The discretionary denial itself highlights the PTAB's recent trend towards increasing such denials, often influenced by factors like parallel litigation and inconsistent legal arguments.

Recommended next steps

• For any defendant facing assertion of US11905896, it is crucial to review the specific decision document for IPR2025-01228 to understand the precise reasons for the discretionary denial. This information, if made public, would clarify the PTAB's concerns and inform future strategies.
• Given that the IPR was denied on discretionary grounds and not on the merits, the patent's claims have not been examined for patentability by the PTAB. This means the claims could still be vulnerable to a well-crafted IPR petition that addresses the discretionary denial factors.
• If parallel district court litigation exists or is contemplated, particular attention must be paid to consistent claim construction positions between the district court and any potential PTAB filings, as inconsistent positions have been a basis for discretionary denial in related cases involving Generac and Champion.
• Consider conducting a thorough prior art search to assess the patentability of the asserted claims. If strong prior art exists, a new IPR petition might be viable if it can mitigate the discretionary denial risks, or alternative invalidity defenses in district court should be pursued.
• Monitor ongoing PTAB developments, especially regarding discretionary denial policies, as these are subject to change.