PTAB challenges

Proceedings overview

There are two AIA trial proceedings on file for US Patent 11885358. One IPR was denied institution, and another is currently pending. This means the patent has largely survived initial challenges, strengthening its defensive posture for the patent owner, Howmet Aerospace Inc., and indicating that an IPR-based defense will be more challenging for a defendant.

IPR2025-01581 — Stanley Black & Decker, Inc. et al. v. Howmet Aerospace Inc.

• Type: Inter Partes Review
• Filed: 2025-10-21
• Status: Discretionary Denial. The PTAB declined to institute review.
• Judge panel: Jennifer L. Hall
• Petition grounds: Specific claims and prior art are not publicly detailed in the provided snippets. However, IPRs typically challenge patentability under 35 U.S.C. §§ 102 and/or 103.
• Institution decision: Denied (2026-02-18). The PTAB denied institution on discretionary grounds. This decision occurred amidst a trend by the USPTO Director to deny IPR institution, especially when parallel district court litigation is underway, and where the district court trial date is set to occur before the PTAB's final written decision. This is influenced by the "Fintiv factors" and the "settled expectations" doctrine, which considers the age of the patent and investment, to limit repetitive or late-stage challenges. The denial was issued by Judge Jennifer L. Hall.
• Defensive value: This proceeding indicates that the patent has survived a challenge, making future IPR attempts on similar grounds potentially more difficult. The discretionary denial, particularly in light of ongoing district court litigation, suggests a strong posture for the patent owner in defending the patent's validity. A defendant would need to present significantly different and compelling prior art or arguments to overcome the discretionary denial hurdle that has become more prevalent in PTAB proceedings.

IPR2026-00268 — CRRC Meishan Co. Ltd. et al. v. Howmet Aerospace Inc.

• Type: Inter Partes Review
• Filed: 2026-02-20
• Status: Pending. The proceeding is ongoing and an institution decision has not yet been issued.
• Judge panel: Not publicly available yet, as the case is still pending institution.
• Petition grounds: Specific claims, prior art, and statutory bases are not publicly detailed in the provided snippets. IPRs typically challenge patentability under 35 U.S.C. §§ 102 and/or 103.
• Institution decision: Not yet issued. The deadline for institution is typically within six months of the petition filing date, absent specific circumstances.
• Defensive value: As this IPR is still pending, its outcome will be crucial. If instituted, it could potentially invalidate claims. If denied institution, it would further strengthen the patent's validity against IPR challenges. Defendants facing assertion of this patent should closely monitor this proceeding, as an institution decision (or lack thereof) will significantly impact the viability of an IPR defense.

Strategic summary

Currently, none of the claims of US Patent 11885358 have been canceled; all claims remain untested by a full IPR trial. One IPR (IPR2025-01581) was denied institution on discretionary grounds, meaning the PTAB chose not to proceed with a full review of the challenged claims. This denial, particularly within the context of parallel district court litigation and the PTAB's increasing tendency towards discretionary denials based on factors like "Fintiv" and "settled expectations," suggests that the patent owner, Howmet Aerospace Inc., has a stronger position in asserting the patent.

The estoppel landscape is favorable for the patent owner. Since IPR2025-01581 was denied institution, no claims were subject to a Final Written Decision. Therefore, the petitioner, Stanley Black & Decker, Inc., and its privies, would likely be estopped under 35 U.S.C. § 315(e)(2) from raising any ground they raised or reasonably could have raised in that petition. For other potential defendants, a wide range of prior art grounds under § 102 and § 103 remains available. The pending IPR2026-00268, filed by CRRC Meishan Co. Ltd., represents the only active challenge. Its institution decision will dictate whether any claims are eventually tested on the merits.

There are signals of a developing pattern in the PTAB's discretionary denials. The denial in IPR2025-01581 is consistent with a broader trend by the USPTO Director to limit IPR institutions, especially in cases with parallel district court litigation and where the district court trial date might precede the PTAB's Final Written Decision. This trend makes it harder for petitioners to succeed in instituting IPRs, creating a more patent owner-friendly environment at the PTAB.

Recommended next steps

• For IPR2026-00268, closely monitor the institution decision. The PTAB generally has a statutory 1-year trial deadline from institution, but an institution decision would be due around August 2026 (six months from the February 20, 2026 filing date).