PTAB challenges

Proceedings overview

One AIA trial proceeding has been filed against US patent 8884373, which was terminated as settled. This means no claims of the patent have been invalidated by the PTAB, leaving the patent's claims intact, though the petitioner in the settled IPR may be subject to estoppel.

IPR2025-01302 — Taiwan Semiconductor Manufacturing Company Ltd. v. Advanced Integrated Circuit Process LLC

• Type: Inter Partes Review
• Filed: 2025-07-15
• Status: Terminated-Settled (The proceeding was halted due to a settlement between the parties before the PTAB reached a final decision on the merits).
• Judge panel: Information regarding the specific judge panel for this proceeding is not publicly available.
• Petition grounds: Details regarding the specific claims challenged, prior art references, and statutory bases (§ 102 / § 103 / § 112) of the petition are not publicly available due to the settlement and lack of an institution decision. The petition was filed and accorded a filing date.
• Institution decision: An institution decision was not publicly issued before the proceeding was terminated due to settlement. Current PTAB practice involves a bifurcated institution process where discretionary factors are considered first by the Director, followed by a merits review by a panel of judges if discretion favors institution. The institution rate for IPRs was notably low in late 2025.
• Final Written Decision (if issued): Not applicable, as the proceeding was terminated due to settlement before a Final Written Decision could be issued.
• Settlement / termination: The proceeding was terminated on 2026-04-10 due to settlement. The specific terms of the settlement are confidential.
• Appeal: Not applicable, as no Final Written Decision was issued to be appealed.
• Defensive value: While the patent's claims were not invalidated by the PTAB, the petitioner, Taiwan Semiconductor Manufacturing Company Ltd., and its privies are likely estopped from raising the same invalidity grounds (or grounds that reasonably could have been raised) against the patent in future proceedings. For other potential defendants, this IPR did not result in any claim cancellation, so the patent remains fully enforceable on its face.

Strategic summary

All claims of US8884373 remain UNTESTED by a PTAB Final Written Decision, as the single IPR filed against it, IPR2025-01302, was terminated due to settlement prior to an institution decision or a full merits review. This means no claims have been canceled by the PTAB, and the patent's scope has not been narrowed through this particular inter partes review.

The estoppel landscape is limited. Taiwan Semiconductor Manufacturing Company Ltd., as the petitioner in IPR2025-01302, and any parties in privity with them, would likely be estopped under 35 U.S.C. § 315(e)(2) from asserting invalidity grounds that were raised or reasonably could have been raised in the petition. However, since the IPR did not proceed to a merits decision, the exact scope of "grounds that reasonably could have been raised" might be subject to interpretation if this issue were to arise in future litigation. For any other potential defendants, all prior-art grounds remain available for challenge.

Regarding pattern signals, only one IPR has been filed against US8884373 by Taiwan Semiconductor Manufacturing Company Ltd. There is no indication of multiple IPRs by the same petitioner or involvement of a defensive aggregator like Unified Patents in challenging this specific patent.

Recommended next steps

As a defendant facing assertion of US8884373 today, it is important to understand that all claims of the patent are currently SUSTAINED in the sense that no PTAB-issued Final Written Decision has invalidated them. The settlement of IPR2025-01302 means the PTAB did not formally rule on the patentability of the challenged claims.

Consider analyzing the petition for IPR2025-01302 if it becomes available, as it would reveal the specific prior art and arguments Taiwan Semiconductor Manufacturing Company Ltd. believed were strong enough to challenge the patent. This information could inform your own prior art search and invalidity contentions.

The absence of a Final Written Decision means there are no active proceedings with upcoming trial-stage milestones for this patent. However, the fact that an IPR was filed and settled could indicate that there are valid challenges to the patent's claims, even if those challenges were not adjudicated by the PTAB. You should conduct your own thorough invalidity analysis of the patent, considering the prior art that may have been identified by the previous petitioner.