PTAB challenges

Proceedings overview

There is one AIA trial proceeding on file for US Patent 10,898,709, which is currently in a "Discretionary Denial" status. This means that the PTAB declined to institute the Inter Partes Review, leaving all claims of the patent untested by this particular proceeding and strengthening the patent owner's position against a defendant relying on IPR-based defenses.

IPR2026-00090 — Nyxoah, Inc. et al. v. Darrell Wagner et al.

• Type: Inter Partes Review
• Filed: 2025-12-18
• Status: Discretionary Denial
• Judge panel:
• Petition grounds: The publicly available information does not specify the exact claims challenged, the prior art cited, or the specific statutory bases (§ 102 / § 103 / § 112) for the petition.
• Institution decision: Denied. The PTAB issued a discretionary denial on 2026-05-15. The reasoning for the discretionary denial is not detailed in the provided information but generally involves factors like parallel litigation, advanced stage of litigation, or inefficient use of Board resources.
• Final Written Decision: Not applicable as institution was denied.
• Settlement / termination: Not applicable as institution was denied.
• Appeal: No Federal Circuit appeal on the merits, as there was no Final Written Decision. The discretionary denial itself could potentially be appealed to the Federal Circuit, but specific appeal information is not publicly detailed.
• Defensive value: This proceeding indicates that the patent has withstood an IPR challenge, at least at the institution stage. A defendant facing assertion of this patent today will find that an IPR based on the same or substantially similar grounds as those raised in IPR2026-00090 will be difficult to institute, given the PTAB's discretionary denial.

Strategic summary

All claims of US Patent 10,898,709 remain UNTESTED by a full inter partes review. IPR2026-00090, filed by Nyxoah, Inc. et al., was denied institution via a discretionary denial, meaning the PTAB chose not to proceed with a full review of the challenged claims. This leaves the patent's claims intact and provides a stronger defensive posture for the patent owner, Inspire Medical Systems Inc.

Regarding the estoppel landscape, as institution was denied, the full breadth of IPR estoppel under § 315(e)(2) may not apply in the same way it would if the IPR had been instituted and a final written decision issued. However, the petitioner (Nyxoah, Inc. et al.) and its privies may be precluded from raising the exact same grounds that were presented to the Board in future PTAB proceedings. For other potential defendants, the prior-art grounds remain largely available, though the denial of institution for IPR2026-00090 could signal weaknesses in the specific arguments or prior art presented in that petition.

The single IPR filing by Nyxoah, Inc. et al. provides a limited pattern signal. It shows that at least one entity attempted to challenge the patent at the PTAB, but the attempt was unsuccessful at the institution phase. There is no information to suggest aggressive PTAB appeals by the patent owner or involvement of a defensive aggregator like Unified Patents.

Recommended next steps

For a defendant facing assertion of this patent, it is important to understand the specific reasoning behind the discretionary denial in IPR2026-00090, if possible. The publicly available information only states the status as "Discretionary Denial" as of 2026-05-15. Reviewing the Board's full decision for IPR2026-00090 on the USPTO PTAB Decisions portal would be crucial to assess what prior art and arguments were considered and why institution was denied. This would help in determining whether new or stronger prior art/arguments could be brought in a subsequent IPR, or if other defensive strategies might be more effective. Since no claims were invalidated, any infringement theories remain potentially viable.