PTAB challenges

Proceedings overview

Currently, there is one active AIA trial proceeding on US Patent 9,185,268. This Inter Partes Review (IPR) is in the "Pending" status, meaning the PTAB has not yet decided whether to institute a trial. For a defendant, this indicates that the patent is currently being challenged, but no claims have been invalidated or sustained by the PTAB yet.

IPR2026-00252 — Dolby Laboratories, Inc. et al. v. InterDigital Madison Patent Holdings SAS

• Type: Inter Partes Review
• Filed: 2026-02-09
• Status: Pending. The petition has been filed, and the PTAB is currently reviewing it to decide whether to institute a trial.
• Judge panel: Not yet publicly available as the institution decision has not been rendered.
• Petition grounds: Details regarding specific claims challenged, prior art cited, and statutory bases (§ 102 / § 103) are not publicly available at this stage without access to the full petition document.
• Institution decision: Not yet issued. The statutory deadline for the institution decision is generally six months from the date of the Patent Owner's preliminary response, or if no preliminary response is filed, six months from the due date of the preliminary response. Given the filing date of 2026-02-09, the institution decision is expected around August 2026.
• Final Written Decision: Not applicable; no decision has been issued.
• Settlement / termination: Not applicable; the proceeding is active and pending institution.
• Appeal: Not applicable.
• Defensive value: This proceeding indicates that Dolby Laboratories, Inc. is actively challenging the patent. If a trial is instituted, it could lead to claim invalidation, which would be highly beneficial for defendants. However, until institution, no definitive impact on the patent's claims exists.

Strategic summary

Currently, all claims of US Patent 9,185,268 remain UNTESTED by the PTAB, as the sole IPR proceeding (IPR2026-00252) is still in the preliminary review phase before institution. No claims have been canceled or sustained by the PTAB at this time.

The estoppel landscape has not yet formed for this patent. If IPR2026-00252 is instituted and proceeds to a Final Written Decision, § 315(e)(2) would bar the petitioner (Dolby Laboratories, Inc. et al.) and their privies from raising any ground that was raised or reasonably could have been raised in the IPR regarding the challenged claims. For a defendant currently facing assertion, this means all prior-art grounds remain available for potential challenges outside of a privy relationship with the current petitioner.

There is no discernible pattern of multiple IPRs on this patent by the same petitioner, as only one IPR has been filed to date. The current assignee, InterDigital Madison Patent Holdings SAS, has not yet had an opportunity to pursue PTAB appeals, as no Final Written Decision has been issued.

Recommended next steps

• Monitor IPR2026-00252 closely: The most critical upcoming milestone is the institution decision, expected around August 2026. This decision will determine whether a trial is instituted and which claims and grounds will be considered. The status can be tracked on the USPTO PTAB E2E portal.
• Review the petition: If you are a defendant, obtaining and reviewing the petition filed by Dolby Laboratories, Inc. for IPR2026-00252 would be crucial. This would provide insight into the specific claims challenged and the prior art asserted, which can inform your own defensive strategy.
• Assess claim independence: Understand which independent claims are being asserted against you in any demand letter and how they relate to the claims challenged in IPR2026-00252.
• Consider joining or filing a separate challenge: Depending on the outcome of the institution decision and your specific situation, you may consider filing your own IPR or, in certain circumstances, exploring options to join the existing IPR if the institution decision is favorable and the grounds align with your interests.