Imperative Care, Inc. v. Inari Medical, Inc.

Imperative Care, Inc., a commercial-stage medical technology company based in Campbell, California, specializes in developing innovative solutions for stroke and other vascular diseases, including products for ischemic and hemorrhagic stroke and venous thromboembolism (VTE). Its product portfolio includes the ZOOM Aspiration System for stroke treatment and vascular products for thrombectomy. Inari Medical, Inc., located in Irvine, California, is a medical device company focused on treating VTE, such as deep vein thrombosis (DVT) and pulmonary embolism (PE), with flagship products like the ClotTriever and FlowTriever systems designed for rapid thrombus removal. Notably, Inari Medical was acquired by Stryker Corporation in February 2025, a move that expanded Stryker's presence in the peripheral thrombectomy market.

This Inter Partes Review (IPR2025-00289) was initiated by Imperative Care, Inc. against Inari Medical, Inc. at the Patent Trial and Appeal Board (PTAB) to challenge the validity of U.S. Patent 11554005. The PTAB has instituted the review of this patent. While a precise one-line technical sketch of Patent 11554005 could not be retrieved from the available search results, it is one of several patents asserted by Inari Medical against Imperative Care in a parallel patent infringement lawsuit, Inari Medical, Inc. v. Imperative Care, Inc., No. 24-cv-3117, in the U.S. District Court for the Northern District of California. In that district court case, Inari Medical has accused Imperative Care's "Symphony" mechanical thrombectomy system, which uses aspiration to remove blood clots from vasculature, of infringement.

The case is notable for several reasons within the medical device industry. It highlights intense competition in the growing market for thrombectomy devices, which are crucial for treating conditions like stroke and VTE. The IPR serves as a defensive action by Imperative Care to challenge the validity of Inari Medical's patent, directly impacting the ongoing district court litigation where a stay was granted in part until February 2026, pending IPR proceedings. The strategic use of IPRs in conjunction with district court patent infringement cases is a common, yet significant, procedural posture in modern patent disputes, aiming to resolve patentability issues at an administrative level which can influence the outcome of the infringement claims.

Imperative Care, Inc. v. Inari Medical, Inc. involves a parallel patent infringement litigation in district court and an Inter Partes Review (IPR) proceeding at the Patent Trial and Appeal Board (PTAB) concerning US Patent No. 11,554,005, among others.

Here is a chronological summary of the key legal developments:

Parallel District Court Litigation: Inari Medical, Inc. v. Imperative Care, Inc. (U.S. District Court for the Northern District of California, Case No. 24-cv-03117-EKL)

• 2024-05-22 – Filing of Complaint: Inari Medical, Inc. (Plaintiff) initiated a patent infringement lawsuit against Imperative Care, Inc. (Defendant) in the U.S. District Court for the Northern District of California. The original complaint asserted infringement of eight patents, including U.S. Patent No. 11,554,005.
• 2024-07-09 – First Amended Complaint: Inari filed a first amended complaint, adding U.S. Patent No. 12,016,580 to the asserted patents.
• 2025-02-07 – Second Amended Complaint: Inari filed a second amended complaint, further adding U.S. Patent Nos. 12,109,384 and 12,156,669.
• 2025-09-29 – Order Denying Motion for Preliminary Injunction: The District Court denied Inari Medical's motion for a preliminary injunction, which sought to stop Imperative Care from making, using, and selling its devices. The court found that Inari was not likely to suffer irreparable harm and could be adequately compensated through damages.
• 2025-09-29 – Order Granting in Part Motion to Stay: The District Court granted Imperative Care's motion to stay the case in part, pending the completion of various IPR proceedings before the PTAB. The stay was initially put in place until February 4, 2026, at which point it was set to be re-evaluated.

PTAB Inter Partes Review (IPR) Proceeding: Imperative Care, Inc. v. Inari Medical, Inc. (IPR2025-00289)

• 2024-12-13 – IPR Petition Filed: Imperative Care, Inc. filed an IPR petition (IPR2025-00289) challenging claims 1-15 of U.S. Patent No. 11,554,005, owned by Inari Medical, Inc. In its petition, Imperative Care argued against discretionary denial under the Fintiv factors, stipulating that if the IPR were instituted, it would not pursue the same grounds, or any other grounds that could have been reasonably raised, in the parallel district court litigation.
• 2025-06-12 – Institution Denied: The PTAB issued a decision denying institution of IPR2025-00289. This denial was based on discretionary considerations, specifically related to "settled expectations." This outcome meant that Imperative Care's attempt to invalidate the '005 patent through this specific IPR was unsuccessful.

Present Posture (as of 2026-06-15):

The IPR (IPR2025-00289) for U.S. Patent No. 11,554,005 has concluded with a denial of institution by the PTAB. The parallel district court litigation (N.D. Cal. Case No. 24-cv-03117-EKL) had been partially stayed until February 4, 2026, pending IPR decisions, and Inari's motion for a preliminary injunction was denied. The current status of the district court case beyond the re-evaluation date of February 4, 2026, is not publicly detailed in the provided search results.

Imperative Care, Inc., the petitioner in IPR2025-00289, is represented by attorneys from Knobbe, Martens, Olson & Bear, LLP.

The following counsel of record represent Imperative Care, Inc.:

• Joshua J. Stowell
  • Role: Lead Counsel
  • Firm: Knobbe, Martens, Olson & Bear, LLP, Irvine, CA.
  • Note: Joshua Stowell is consistently listed as an attorney for Imperative Care in multiple related Inter Partes Review proceedings before the PTAB.
• Joseph R. Re
  • Role: Counsel
  • Firm: Knobbe, Martens, Olson & Bear, LLP, Irvine, CA.
  • Note: Joseph R. Re is listed as counsel for Imperative Care in several related IPR proceedings. He is known for his extensive experience in patent litigation.
• Brian C. Barnes
  • Role: Counsel
  • Firm: Knobbe, Martens, Olson & Bear, LLP, Irvine, CA.
  • Note: Brian C. Barnes is also listed as counsel for Imperative Care in related IPR proceedings.

In IPR2025-00289, Inari Medical, Inc., the Patent Owner, is represented by counsel including Joseph Hamilton. While the specific firm and role are not explicitly detailed for this exact IPR in the immediate search results, related IPR proceedings (IPR2025-01025, IPR2025-01021, IPR2025-00728) identify "Hamilton, Joseph et al." as Respondent Counsel for Inari Medical, Inc..

Further details on Joseph Hamilton's firm and experience would require additional searching. However, based on the provided search results, the following can be identified:

• Joseph Hamilton
  • Role: Respondent Counsel (likely Lead Counsel or significant counsel, given "et al." frequently follows his name in multiple related IPRs).
  • Firm: (Not explicitly stated in provided search results for Inari Medical in IPR2025-00289 or related IPRs).
  • Note: Joseph Hamilton is listed as counsel for Inari Medical in multiple Inter Partes Review proceedings before the PTAB.