PTAB challenges

Proceedings overview

Only one AIA trial proceeding is on file for US patent 10828345. This proceeding, IPR2025-01269, resulted in a denial of institution, meaning no claims were ever challenged in a full trial at the PTAB. For a defendant, this means the patent has not been subjected to a full IPR trial and its claims remain untested by a final written decision.

IPR2025-01269 — Fresenius Kabi SwissBiosim, GmbH et al. v. George D. Yancopoulos (Regeneron Pharmaceuticals Inc.)

• Type: Inter Partes Review
• Filed: 2025-07-14
• Status: Institution Denied – The PTAB declined to institute a trial based on the merits of the petition.
• Judge panel: Lead Judge Michael P. Tierney, Administrative Patent Judge S. Kevin Walling, Administrative Patent Judge Jennifer L. Tourtelott.
• Petition grounds: The petition challenged claims 1-11 of US Patent No. 10,828,345 as unpatentable under 35 U.S.C. § 103 over a combination of prior art references. Specifically, the grounds included various combinations of Schmidt 2011, Korobelnik 2011, Lucentis PI 2010, Chung 2010, and Campochiaro 2010.
• Institution decision: Denied on 2026-01-14. The panel found that the petitioner failed to demonstrate a reasonable likelihood of prevailing with respect to any of the challenged claims. The Board determined that the petitioner's proposed obviousness combinations did not adequately account for or overcome the unexpected results and improved dosing regimens claimed in the patent. The petition failed to show that a skilled artisan would have been motivated to combine the prior art references to achieve the claimed every-12-week dosing for tertiary doses, particularly given the known monthly dosing of ranibizumab.
• Final Written Decision: Not applicable; institution was denied, so no trial proceeded to a Final Written Decision.
• Settlement / termination: Not applicable. The proceeding concluded with the denial of institution.
• Appeal: Not applicable; institution was denied.
• Defensive value: The patent owner successfully defended against this IPR challenge at the institution stage. This means that a defense against the patent based on the specific prior art and obviousness arguments raised in this petition (Schmidt 2011, Korobelnik 2011, Lucentis PI 2010, Chung 2010, Campochiaro 2010) will be harder for a defendant, as the PTAB has already found these grounds insufficient to institute a trial on claims 1-11.

Strategic summary

All claims (1-11) of US patent 10828345 remain UNTESTED by a Final Written Decision. IPR2025-01269, which sought to challenge all claims, was denied institution. This means the merits of the patentability of these claims under the petitioned grounds were not fully adjudicated in a trial.

Regarding the estoppel landscape, 35 U.S.C. § 315(e)(2) will bar Fresenius Kabi SwissBiosim, GmbH (and any privies) from asserting in future district court litigation or other PTAB proceedings that claims 1-11 are unpatentable on any ground that was raised or reasonably could have been raised in IPR2025-01269. For other potential defendants, the specific combinations of prior art (Schmidt 2011, Korobelnik 2011, Lucentis PI 2010, Chung 2010, and Campochiaro 2010) used in the denied petition might be considered a less viable path for a new IPR given the PTAB's reasoning for denial. However, different combinations of prior art, or different statutory bases (e.g., § 102 anticipation), would not be estopped for new petitioners.

There is no discernible pattern signal of aggressive PTAB appeals by the patent owner or multiple IPRs by the same petitioner, as this is the only proceeding on file that progressed to an institution decision. The petitioner, Fresenius Kabi SwissBiosim, GmbH, is a biosimilar developer, which often indicates an interest in challenging pharmaceutical patents.

Recommended next steps

Given the denial of institution for IPR2025-01269, claims 1-11 of US patent 10828345 are considered patentable as far as the PTAB is concerned for the specific arguments made in that petition. The full institution decision for IPR2025-01269 can be reviewed at the USPTO PTAB E2E portal. A defendant facing assertion of this patent should carefully review the denial decision to understand the specific reasoning why institution was not granted. This would inform whether new IPR petitions could be filed using different prior art combinations or arguments to avoid the same outcome, or if other defensive strategies (e.g., non-infringement) would be more appropriate.