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

Inari Medical, Inc. v. Imperative Care, Inc. et al. is a patent infringement lawsuit involving competing medical device manufacturers in the thrombectomy market. Plaintiff Inari Medical, Inc., a commercial-stage company based in Irvine, California, specializes in developing catheter-based mechanical thrombectomy systems, such as its FlowTriever and ClotTriever products, for treating venous diseases like deep vein thrombosis (DVT) and pulmonary embolism (PE). Defendants Imperative Care, Inc., a Campbell, California-based medical technology company, and its wholly-owned subsidiary Truvic Medical, Inc., focus on solutions for thromboembolic disease, including stroke and peripheral vascular issues.

The core of the dispute centers on Imperative Care and Truvic Medical's Symphony thrombectomy system, which Inari alleges infringes its patents. The Symphony system is designed for continuous aspiration to remove thrombus from peripheral vasculature, employing a mechanical assist with a helical design and flexible catheters. The primary patent asserted in this litigation is U.S. Patent No. 11,969,333, with claims 5 and 24 specifically at issue, which generally pertains to medical devices for thrombectomy systems and includes aspects related to reintroducing filtered blood.

The case is active in the U.S. District Court for the Northern District of California, under case number 5:24-cv-03117-EKL, with Judge E. Lee presiding. The Northern District of California is a notable venue in patent litigation, known for its inclination to grant stays pending Patent Trial and Appeal Board (PTAB) proceedings and its receptiveness to early dispositive motions, which can be favorable to defendants. The case is currently stayed pending the outcome of multiple Inter Partes Review (IPR) proceedings, which Imperative Care has initiated against Inari's patents. A preliminary injunction sought by Inari was denied by the court, largely due to Imperative Care raising substantial questions about the validity of the asserted patents in the parallel IPR proceedings, and a finding that any potential harm to Inari could be compensated by monetary damages. This litigation underscores the intense competition within the thrombectomy device market, made even more significant by Stryker Corporation's acquisition of Inari Medical for approximately $4.9 billion in February 2025, positioning this patent dispute at the forefront of a major medical technology enterprise.

Key Legal Developments and Outcome for Inari Medical, Inc. v. Imperative Care, Inc. et al.

The patent infringement litigation, Inari Medical, Inc. v. Imperative Care, Inc. et al., Case No. 5:24-cv-03117-EKL, commenced in the U.S. District Court for the Northern District of California on May 22, 2024, and is currently stayed pending Inter Partes Review (IPR) proceedings. Inari Medical, Inc. ("Inari") initially asserted infringement of eight patents, including U.S. Patent No. 11,969,333 ('333 patent). Inari later filed a first amended complaint on July 9, 2024, adding U.S. Patent No. 12,016,580, and a second amended complaint on February 7, 2025, adding U.S. Patent No. 12,109,384. Inari specifically asserted claims 5 and 24 of the '333 patent, which concern a method requiring "reintroducing the filtered blood."

Key Legal Developments:

• Filing & Initial Pleadings:

  • 2024-05-22: Inari Medical, Inc. filed its initial complaint asserting infringement of eight patents.
  • 2024-07-09: Inari filed a first amended complaint, adding U.S. Patent No. 12,016,580.
  • 2025-02-07: Inari filed a second amended complaint, adding U.S. Patent No. 12,109,384.
  • While specific filing dates for Imperative Care's answer and any counterclaims are not explicitly detailed in the public records available, their engagement in discovery disputes and opposition to Inari's motions indicate that responsive pleadings have been filed. Imperative Care's opposition to Inari's motion for leave to file a third amended complaint was filed on March 26, 2025.

• Pre-trial Motions of Substance:

  • 2025-09-29: The court denied Inari's motion for a preliminary injunction. The court found that Imperative Care raised substantial questions about the validity of the asserted patents (specifically U.S. Patent Nos. 11,844,921 and 11,974,910, which were the focus of the preliminary injunction motion), indicating Inari was not likely to succeed on the merits. Additionally, the court determined that Inari would not suffer irreparable harm in the absence of an injunction and could be adequately compensated through monetary damages if it ultimately prevailed.
  • 2025-09-29: The District Court granted in part Imperative Care's motion to stay the case, initially staying the action in its entirety until February 4, 2026. This decision was made pending the completion of IPR proceedings at the Patent Trial and Appeal Board (PTAB), with a re-evaluation scheduled for a case management conference on January 28, 2026. The court noted that a stay would likely simplify the case and conserve resources.
  • 2026-01-27: The parties filed a joint stipulation to continue the stay of litigation pending IPR decisions and to vacate the upcoming case management conference. This stipulation was subsequently ordered by the court, extending the stay.

• Claim Construction (Markman) Outcomes:

  • The court has not issued a claim construction order. Due to Inari's multiple amended complaints and the subsequent stay, the parties have not yet briefed claim construction.

• Discovery Milestones:

  • Limited expert discovery focused on the two patents at issue in the preliminary injunction motion occurred prior to the stay. A discovery dispute concerning Imperative Care's blood return system and its relevance to claims 5 and 24 of the '333 patent was documented in a joint letter brief on March 14, 2025.

• Parallel PTAB IPR Proceedings:

  • Imperative Care has filed numerous IPR petitions challenging Inari's asserted patents. By September 29, 2025, Imperative Care had filed ten IPR petitions, and the PTAB had granted institution for three out of four initial institution decisions.
  • IPR2025-01021 (U.S. Patent No. 11,969,333): This IPR was filed by Imperative Care, Inc. on May 19, 2025, challenging claims 1-12, 14-31, and 33-38 of the '333 patent. The PTAB instituted trial on this IPR on December 10, 2025. As of May 17, 2026, a final written decision for IPR2025-01021 is not yet available in the provided search results.
  • Other IPRs with institution decisions include IPR2024-01157, IPR2025-00156, IPR2025-00289, and IPR2025-00728, which were instituted by April 8, 2026. IPR2025-01025, challenging U.S. Patent No. 11,974,910, was instituted on December 11, 2025. Final Written Decisions were issued for IPR2024-01157 and IPR2025-00156 on April 8, 2026.

Current Posture:

The case remains active but is stayed in the U.S. District Court for the Northern District of California, as the stay granted on September 29, 2025, was continued on January 27, 2026, pending the outcome of multiple IPR proceedings. No trial date has been set, and claim construction has not occurred. The litigation's progression is contingent upon the results of the ongoing IPRs, particularly IPR2025-01021 concerning the '333 patent.

Inari Medical, Inc. is represented by attorneys from Perkins Coie LLP. The identified counsel of record for the plaintiff includes:

• Ramsey M. Al-Salam

  • Role: Counsel for Plaintiff.
  • Firm: Perkins Coie LLP, San Francisco, CA.
  • Experience Note: Al-Salam filed a consent/declination to proceed before a U.S. Magistrate Judge on behalf of Inari Medical, Inc. in this case. Perkins Coie has a strong patent litigation practice with experience in medical devices, regularly representing clients in high-stakes patent matters nationwide.

• Joseph P. Hamilton

  • Role: Counsel for Patent Owner (Inari Medical Inc.).
  • Firm: Perkins Coie LLP, Los Angeles, CA.
  • Experience Note: Hamilton is listed as counsel for Inari Medical in related Inter Partes Review (IPR) proceedings. Perkins Coie's patent litigators are skilled at analyzing technology and have won jury trials in various districts.

• Paul T. Parker

  • Role: Counsel for Patent Owner (Inari Medical Inc.).
  • Firm: Perkins Coie LLP, Los Angeles, CA.
  • Experience Note: Parker is identified as counsel for Inari Medical in related IPR proceedings. He is a registered patent attorney.

• Matthew Williams

  • Role: Counsel for Patent Owner (Inari Medical Inc.).
  • Firm: Perkins Coie LLP, Seattle, WA.
  • Experience Note: Williams is listed as counsel for Inari Medical in related IPR proceedings. He is a registered patent attorney.

• Daniel Keese

  • Role: Counsel for Plaintiff.
  • Firm: Perkins Coie LLP, Seattle, WA.
  • Experience Note: Keese is listed as an attorney for Inari Medical, Inc. in a joint letter brief filed in the district court case.

• A. Tessar

  • Role: Counsel for Plaintiff (admitted pro hac vice).
  • Firm: Perkins Coie LLP, Denver, CO.
  • Experience Note: Tessar is listed as an attorney for Inari Medical, Inc. in a joint letter brief filed in the district court case.

• Trevor Bervik

  • Role: Counsel for Plaintiff (admitted pro hac vice).
  • Firm: Perkins Coie LLP, Denver, CO.
  • Experience Note: Bervik is listed as an attorney for Inari Medical, Inc. in a joint letter brief filed in the district court case.

The following counsel of record represent the defendant Imperative Care, Inc. in Inari Medical, Inc. v. Imperative Care, Inc. et al. (5:24-cv-03117-EKL):

• Joseph R. Re

  • Role: Lead Counsel
  • Firm: Knobbe, Martens, Olson & Bear, LLP, Irvine, CA
  • Experience Note: Nationally recognized trial and appellate attorney with extensive experience in high-stakes medical device patent litigation, including a successful defense of Imperative Care in this case against a preliminary injunction.

• Joshua J. Stowell

  • Role: Lead Counsel
  • Firm: Knobbe, Martens, Olson & Bear, LLP, Irvine, CA
  • Experience Note: Co-chair of Knobbe Martens' Medical Device Litigation practice, with extensive experience in patent litigation involving various medical technologies, including thrombectomy systems, and a leading specialist in PTAB proceedings. He is listed as an attorney for Imperative Care in the preliminary injunction denial for this case.

• Brian C. Barnes

  • Role: Counsel
  • Firm: Knobbe, Martens, Olson & Bear, LLP, Irvine, CA
  • Experience Note: Focuses on strategic patent litigation across biotechnology, pharmaceuticals, and medical devices, with experience in cases involving vascular technologies such as thrombectomy systems, and recognized for securing significant wins in federal district courts, the Federal Circuit, and the PTAB.

No specific counsel of record for Truvic Medical, Inc. could be identified in the available public information regarding this district court case. It is possible they are represented by the same counsel as Imperative Care, Inc., or their counsel has not yet been explicitly named in public filings accessible through the searches conducted.