PTAB challenges

Proceedings overview

There is one active AIA trial proceeding on file for US Patent 12,375,890. This Inter Partes Review (IPR) is currently pending institution, meaning the defensive posture for a defendant is still developing.

IPR2026-00349 — AT&T Services, Inc. et al. v. John Marvin Suzuki et al

• Type: Inter Partes Review
• Filed: 2026-05-05
• Status: Pending. Last modified 2026-05-26.
• Judge panel: Not yet publicly available.
• Petition grounds: Not yet publicly available.
• Institution decision: Not yet issued. The institution decision deadline is typically 6 months from the filing date.
• Final Written Decision: Not applicable; no institution decision has been rendered.
• Settlement / termination: Not applicable.
• Appeal: Not applicable.
• Defensive value: As this IPR is in its early stages, its direct defensive value is currently limited. However, it indicates that AT&T Services, Inc. and potentially other parties believe there are grounds to challenge the patent's validity. If the IPR is instituted, it will create an opportunity to invalidate some or all of the challenged claims, which could significantly weaken the patent's enforceability.

Strategic summary

As of today, May 29, 2026, all claims of US Patent 12,375,890 are UNTESTED through a final written decision in an AIA trial. One IPR (IPR2026-00349) has been filed by AT&T Services, Inc. et al. and is currently pending institution. The outcome of this proceeding will be crucial in determining which, if any, claims are canceled or sustained.

Regarding the estoppel landscape, if IPR2026-00349 is instituted and proceeds to a Final Written Decision, the petitioners (AT&T Services, Inc. et al. and their privies) would be barred under 35 U.S.C. § 315(e)(2) from raising any ground they raised or reasonably could have raised in a subsequent civil action or another proceeding before the Office. For other defendants, prior-art grounds not addressed or reasonably available to the petitioners in this IPR would remain available for challenge.

There are no apparent pattern signals such as multiple IPRs on this patent by the same petitioner, aggressive PTAB appeals by the patent owner, or the involvement of a defensive aggregator at this early stage.

Recommended next steps

For a defendant facing assertion of US Patent 12,375,890, the primary next step is to closely monitor IPR2026-00349. Key trial-stage milestones include the institution decision deadline (approximately November 5, 2026). The institution decision, if it occurs, will detail the specific claims and prior art grounds that the PTAB will review. If the IPR is instituted, then tracking the oral hearing and the Final Written Decision due date (typically one year from institution) will be critical.

The absence of prior PTAB activity means the patent has not yet undergone significant scrutiny in post-grant proceedings.