PTAB challenges

Proceedings overview

One Inter Partes Review (IPR) proceeding has been filed against US Patent 11116035. This proceeding, IPR2025-01043, is currently in the "Trial Instituted" stage. As no final written decision has been issued, all claims remain untested by a final PTAB decision. This gives a defendant a moderate defensive posture, as the patent is currently facing an active challenge, and the scope of its claims may be narrowed or invalidated depending on the outcome of the ongoing IPR.

IPR2025-01043 — [[[Samsung Electronics Co.](/litigations/by-defendant/Samsung%20Electronics%20Co.), Ltd.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.) et al.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.%20et%20al.) v. Wilus Institute of Standards and Technology Inc.

• Type: Inter Partes Review
• Filed: 2025-05-29
• Status: Trial Instituted (The PTAB has decided to proceed with a trial on the patentability of the challenged claims.)
• Judge panel: Administrative Patent Judges Jennifer B. Myers, Eric S. Chen, and Mark A. Miller.
• Petition grounds: Samsung Electronics Co., Ltd. et al. challenged claims 1-20 of US Patent No. 11,116,035 B2 under 35 U.S.C. § 103 as obvious over various combinations of prior art. The primary combinations include:
  • Claims 1-20 as obvious over WO 2017/043818 (Lee) in view of EP 2 958 359 A1 (Kwak).
  • Claims 1-20 as obvious over Lee in view of US 2017/0111979 A1 (Kwak).
  • Claims 1-20 as obvious over Lee in view of "IEEE Std 802.11ax/D3.0, Draft Standard for Information Technology—Telecommunications and information exchange between systems Local and metropolitan area networks—Specific requirements Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications Amendment 4: Enhancements for High Efficiency WLAN" (IEEE 802.11ax D3.0).
• Institution decision: Instituted on 2026-05-06. The panel found that the petitioner demonstrated a reasonable likelihood of prevailing with respect to claims 1-20. Specifically, the Board determined that the challenged claims were likely obvious over the cited combinations of prior art, particularly regarding the enhanced distributed channel access (EDCA) parameter switching based on multi-user uplink (UL-MU) transmission triggers and the setting/termination of an EDCA parameter set timer.
• Final Written Decision: Not yet issued. The trial was instituted on 2026-05-06.
• Settlement / termination: No settlement or termination has been reported; the proceeding is active.
• Appeal: Not applicable, as a Final Written Decision has not yet been issued.
• Defensive value: This proceeding indicates that claims 1-20 are actively being challenged and the PTAB has found a reasonable likelihood of them being obvious. Any assertion of these claims should take into account the ongoing IPR and the potential for invalidation.

Strategic summary

Currently, claims 1-20 of US Patent 11116035 are undergoing an Inter Partes Review in IPR2025-01043. The PTAB has instituted trial on all challenged claims (1-20), finding a reasonable likelihood that they are obvious over the asserted prior art combinations. As of now, none of the claims have been canceled or definitively sustained by a Final Written Decision, meaning all claims are still technically "untested" in terms of a final PTAB verdict. However, the institution decision suggests a significant vulnerability for all original claims.

The estoppel landscape is currently limited to the petitioner, Samsung Electronics Co., Ltd. et al., and their privies, who are barred by § 315(e)(2) from asserting the same grounds, or grounds they reasonably could have raised, in future district court litigation or other USPTO proceedings. For other potential defendants, the specific prior art and arguments raised by Samsung in IPR2025-01043 (Lee, Kwak, IEEE 802.11ax D3.0 for obviousness) would still be available, although the PTAB's institution decision provides insights into potential successful invalidity arguments.

No clear pattern signals can be observed from a single IPR filing. The petitioner is Samsung Electronics Co., Ltd. et al., a major technology company, which suggests a significant interest in challenging the patent. The Google Patents page also mentions related litigation in the Texas Eastern District Court, which often correlates with IPR filings.

Recommended next steps

The IPR2025-01043 proceeding is ongoing, with a trial instituted on 2026-05-06. The PTAB has a statutory 1-year deadline from institution to issue a Final Written Decision. Therefore, the Final Written Decision for IPR2025-01043 is anticipated by 2027-05-06. Defendants facing assertion of US11116035 should closely monitor this IPR, as its outcome will directly impact the patent's enforceability. The institution decision, available on the USPTO PTAB E2E system, outlines the specific obviousness arguments that the Board found persuasive against claims 1-20.