PTAB challenges

Based on the provided information and public records, here is an analysis of the AIA trial proceedings for U.S. Patent 12,290,598.

Proceedings overview

There is one active Post-Grant Review (PGR) proceeding filed against this patent; the trial has been instituted, meaning the patent's validity is currently under significant challenge at the PTAB. For a defendant, this is a favorable defensive posture, as the PTAB has already determined that the petitioner is likely to succeed in proving at least one challenged claim is unpatentable.

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PGR2025-00086 — Dr. Falk Pharma GmbH v. Ellodi Pharmaceuticals LP

• Type: Post-Grant Review
• Filed: 2025-09-19
• Status: Trial Instituted — This means the Patent Trial and Appeal Board (PTAB) reviewed the petition and determined that the petitioner has shown it is more likely than not that at least one of the challenged patent claims is unpatentable. The trial is currently in progress.
• Judge panel: APJ Michael P. Tierney, APJ Bryan F. Moore, APJ Scott B. Howard.
• Petition grounds: The petition challenged all claims (1-25) of the '598 patent. The grounds for the challenge included patent-ineligible subject matter under 35 U.S.C. § 101, lack of adequate written description and enablement under 35 U.S.C. § 112, and obviousness under 35 U.S.C. § 103 based on multiple prior art references.
• Institution decision: The trial was instituted on 2026-03-25. The PTAB panel found that the petitioner, Dr. Falk Pharma GmbH, had met the institution standard by demonstrating a likelihood of prevailing on its arguments that claims 1-25 are unpatentable on the asserted § 101, § 112, and § 103 grounds.
• Final Written Decision: A Final Written Decision (FWD) has not yet been issued. The statutory deadline for the PTAB to issue its decision is one year from the institution date, which is 2027-03-25.
• Settlement / termination: There is no public record of a settlement; the proceeding is active.
• Appeal: Not applicable, as no Final Written Decision has been issued.
• Defensive value: This active proceeding provides very high defensive value. The fact that the PTAB instituted trial on all claims and on multiple statutory grounds signals a significant risk that the patent claims will be canceled. Any defendant facing an assertion of this patent should closely monitor this PGR, as its outcome could invalidate the claims at issue.

Strategic summary

• Claim Status: Currently, all claims (1-25) of US Patent 12,290,598 are UNTESTED by a final PTAB decision. However, all claims are under active challenge in the instituted PGR2025-00086. No claims have been finally canceled or sustained.

• Estoppel landscape: For a new defendant, no estoppel applies. All prior art and invalidity grounds remain available. The arguments and evidence presented in PGR2025-00086 by Dr. Falk Pharma GmbH provide a valuable roadmap for a potential defense or a separate PTAB challenge. Once the Final Written Decision in PGR2025-00086 is issued, the petitioner (Dr. Falk Pharma GmbH) and any real parties in interest will be estopped under 35 U.S.C. § 325(e) from raising any invalidity ground in a district court or another PTAB proceeding that they raised or reasonably could have raised during the PGR.

• Pattern signals: The petitioner, Dr. Falk Pharma GmbH, appears to be a competitor in the pharmaceutical space. Filing a PGR is an aggressive move available only within the first nine months of a patent's grant, and it allows for a broader range of invalidity arguments (like § 101 and § 112) than the more common Inter Partes Review (IPR). This indicates a serious challenge to the patent's fundamental validity. The patent owner, Ellodi Pharmaceuticals LP, is now forced to defend the patent in a trial that has a high likelihood of resulting in claim cancellation.

Recommended next steps

As a defendant currently facing an assertion of US Patent 12,290,598, the most critical action is to monitor the active PGR proceeding.

• Monitor Active Proceeding: The instituted trial in PGR2025-00086 is the most important near-term event. You can follow the case and review all public documents, including the petition and the institution decision, via the USPTO's PTAB E2E portal.
  • Institution Decision: Review the Board's reasoning for instituting the trial, issued on 2026-03-25. This document details the specific arguments and evidence the PTAB found persuasive.
  • Upcoming Milestones: Key dates to watch for in the trial schedule are the Patent Owner's Response, the Oral Hearing (typically held 2-3 months before the FWD), and the Final Written Decision deadline on 2027-03-25. The outcome of this trial may fully resolve the validity of the claims asserted against you.
• Leverage Arguments: The arguments and prior art cited by Dr. Falk Pharma GmbH can be directly leveraged in your own defense, potentially in a motion to stay any district court litigation pending the outcome of the PGR.