PTAB challenges

Proceedings overview

There is one active AIA trial proceeding on US Patent 11041149: IPR2026-00313. The proceeding is currently in the pre-institution phase, meaning no claims have been challenged or validated by the PTAB yet. This gives a defendant a neutral defensive posture as the patent's validity in an IPR context is still to be determined.

IPR2026-00313 — Merck Sharp & Dohme LLC v. Halozyme Inc.

• Type: Inter Partes Review
• Filed: 2026-03-23
• Status: Pending. The petition has been filed and is awaiting the Patent Trial and Appeal Board's decision on whether to institute a trial.
• Judge panel: Information on the specific judge panel is not publicly available until the institution decision is issued.
• Petition grounds: A search for publicly available information on IPR2026-00313's petition grounds, including specific claims, prior art, and statutory basis (§ 102 / § 103 / § 112), is not typically disclosed in general public databases before institution.
• Institution decision: As of today (2026-05-29), an institution decision has not been issued. The statutory deadline for the PTAB to decide whether to institute an IPR trial is six months from the petition's filing date, which would be approximately September 23, 2026.
• Final Written Decision (if issued): Not applicable; the proceeding is in the pre-institution phase.
• Settlement / termination: Not applicable; the proceeding is in the pre-institution phase.
• Appeal: Not applicable; the proceeding is in the pre-institution phase.
• Defensive value: This IPR is currently pending institution. Its outcome could significantly impact the patent's enforceability. For a defendant, this means the patent's validity is currently being challenged, but no claims have been invalidated or confirmed. If institution is denied, it strengthens the patent owner's position against future IPRs on similar grounds. If instituted, the outcome will depend on the Final Written Decision, which is still many months away.

Strategic summary

As of May 29, 2026, all claims of US Patent 11041149 remain untested by a Final Written Decision at the PTAB. There is one active Inter Partes Review, IPR2026-00313, filed by Merck Sharp & Dohme LLC. This proceeding is in its early stages, and the PTAB has not yet decided whether to institute a trial. Therefore, no claims of 11041149 are currently CANCELED or SUSTAINED by a PTAB FWD. All claims are effectively UNTESTED in the context of an AIA trial.

The estoppel landscape is not yet relevant as no trial has been instituted, and consequently, no Final Written Decision has been rendered. Therefore, § 315(e)(2) (petitioner estoppel) does not yet apply to Merck Sharp & Dohme LLC, and all prior-art grounds remain theoretically available to potential defendants.

Regarding pattern signals, a single IPR filing by Merck Sharp & Dohme LLC is observed. It is too early to determine if there will be multiple filings or aggressive PTAB appeal strategies by the patent owner, Halozyme Inc., as the first IPR has not even reached institution.

Recommended next steps

• Monitor IPR2026-00313: Closely track the institution decision for IPR2026-00313. The institution decision deadline is around September 23, 2026. This decision will be a critical milestone, indicating whether the PTAB believes there's a reasonable likelihood that at least one claim is unpatentable. Information will be available via the USPTO PTAB E2E system.
• Analyze Petition if Instituted: If the IPR is instituted, obtain and thoroughly analyze the petition to understand the specific prior art and arguments being used against the claims. This will inform potential defensive strategies if the patent is asserted.
• Assess Independent Claims: The patent's independent claims (Claims 1, 13, 16, 19, and 22 as noted in the patent summary) are the primary targets in an IPR. Understanding which of these are challenged and on what grounds is crucial.
• Consider potential for parallel District Court litigation: The patent explicitly notes a US case filed in New Jersey District Court (2:25-cv-03179). The outcome of IPR2026-00313 could influence this litigation, but the IPR and district court proceedings run on separate tracks.## Proceedings overview
  There is one active AIA trial proceeding on US Patent 11041149: IPR2026-00313. The proceeding is currently in the pre-institution phase, meaning no claims have been challenged or validated by the PTAB yet. This gives a defendant a neutral defensive posture as the patent's validity in an IPR context is still to be determined.

IPR2026-00313 — Merck Sharp & Dohme LLC v. Halozyme Inc.

• Type: Inter Partes Review
• Filed: 2026-03-23
• Status: Pending. The petition has been filed and is awaiting the Patent Trial and Appeal Board's decision on whether to institute a trial.
• Judge panel: Information on the specific judge panel is not publicly available until the institution decision is issued.
• Petition grounds: A search for publicly available information on IPR2026-00313's petition grounds, including specific claims, prior art, and statutory basis (§ 102 / § 103 / § 112), is not typically disclosed in general public databases before institution.
• Institution decision: As of today (2026-05-29), an institution decision has not been issued. The statutory deadline for the PTAB to decide whether to institute an IPR trial is six months from the petition's filing date, which would be approximately September 23, 2026.
• Final Written Decision (if issued): Not applicable; the proceeding is in the pre-institution phase.
• Settlement / termination: Not applicable; the proceeding is in the pre-institution phase.
• Appeal: Not applicable; the proceeding is in the pre-institution phase.
• Defensive value: This IPR is currently pending institution. Its outcome could significantly impact the patent's enforceability. For a defendant, this means the patent's validity is currently being challenged, but no claims have been invalidated or confirmed. If institution is denied, it strengthens the patent owner's position against future IPRs on similar grounds. If instituted, the outcome will depend on the Final Written Decision, which is still many months away.

Strategic summary

As of May 29, 2026, all claims of US Patent 11041149 remain untested by a Final Written Decision at the PTAB. There is one active Inter Partes Review, IPR2026-00313, filed by Merck Sharp & Dohme LLC against Halozyme Inc. This proceeding is in its early stages, and the PTAB has not yet decided whether to institute a trial. Therefore, no claims of 11041149 are currently CANCELED or SUSTAINED by a PTAB FWD. All claims are effectively UNTESTED in the context of an AIA trial.

The estoppel landscape is not yet relevant as no trial has been instituted, and consequently, no Final Written Decision has been rendered. Therefore, § 315(e)(2) (petitioner estoppel) does not yet apply to Merck Sharp & Dohme LLC, and all prior-art grounds remain theoretically available to potential defendants.

Regarding pattern signals, a single IPR filing by Merck Sharp & Dohme LLC is observed. It is too early to determine if there will be multiple filings or aggressive PTAB appeal strategies by the patent owner, Halozyme Inc., as the first IPR has not even reached institution. The USPTO Director now handles all IPR institution decisions, which are often issued as summary notices without detailed reasoning, though recent precedential and informative decisions provide some guidance on discretionary considerations for institution. New USPTO guidance also indicates that the PTAB may place increased weight on domestic manufacturing activity and the interests of small businesses when deciding whether to institute IPRs.

Recommended next steps

• Monitor IPR2026-00313: Closely track the institution decision for IPR2026-00313. The institution decision deadline is around September 23, 2026. This decision will be a critical milestone, indicating whether the PTAB believes there's a reasonable likelihood that at least one claim is unpatentable. Information will be available via the USPTO PTAB E2E system.
• Analyze Petition if Instituted: If the IPR is instituted, obtain and thoroughly analyze the petition to understand the specific prior art and arguments being used against the claims. This will inform potential defensive strategies if the patent is asserted.
• Assess Independent Claims: The patent's independent claims (Claims 1, 13, 16, 19, and 22 as noted in the patent summary) are the primary targets in an IPR. Understanding which of these are challenged and on what grounds is crucial.
• Consider potential for parallel District Court litigation: The patent explicitly notes a US case filed in New Jersey District Court (2:25-cv-03179). The outcome of IPR2026-00313 could influence this litigation, but the IPR and district court proceedings run on separate tracks.