Untitled case

The patent infringement litigation, Case No. 5:24-cv-03117, is unfolding in the United States District Court for the Northern District of California, San Jose Division. The plaintiff, Inari Medical, Inc., and the defendant, Imperative Care, Inc., are both operating companies in the medical device industry, specializing in technologies for treating venous thromboembolism and stroke. The case has been assigned to District Judge Eumi K. Lee, with Judge Susan van Keulen as the referred judge.

The core of the dispute revolves around Inari Medical's allegations that Imperative Care's medical devices, including its "Symphony system," infringe its patents related to mechanical thrombectomy systems used to remove blood clots from veins. While the case generally involves a portfolio of Inari's patents, a preliminary injunction motion filed by Inari specifically asserted U.S. Patents Nos. 11,844,921 and 11,974,910, which relate to components such as valves within these clot-removal devices. US Patent 12156669, listed in the prompt, is titled "Method and system for retrieving a thrombus from a blood vessel using a catheter having a collapsible engagement member" and broadly describes systems and methods for extracting blood clots from vessels.

The procedural posture of the case is notable due to the denial of Inari's motion for a preliminary injunction in September 2025, with the court finding a lack of irreparable harm and nexus to the asserted patent claims. Subsequently, the district court action has been stayed in its entirety, pending the outcome of multiple inter partes review (IPR) proceedings filed by Imperative Care against Inari's patents before the Patent Trial and Appeal Board (PTAB). The Northern District of California is a significant venue for patent litigation, known for its experienced judiciary, adherence to local patent rules, and a tendency to grant early dispositive motions and motions to stay cases pending IPRs, which often benefits defendants in patent disputes. This interplay between district court litigation and PTAB challenges underscores the strategic complexity in this competitive medical device market.

Patent Infringement Litigation: Inari Medical, Inc. v. Imperative Care, Inc., et al.

Case Number: 5:24-cv-03117
Court: U.S. District Court for the Northern District of California
Patents at Issue: U.S. Patent Nos. 11,844,921; 11,974,910; and 11,969,333. (Note: The patent 12156669 specified in the prompt does not appear to be directly asserted in this case based on available public records. The asserted patents primarily relate to medical devices for treating blood clots.)

This litigation, filed in the Northern District of California, involves a patent infringement dispute between medical device manufacturers. The case has seen a denial of a preliminary injunction, significant discovery disputes, and a stay pending multiple inter partes review (IPR) proceedings at the Patent Trial and Appeal Board (PTAB). The district court case was marked as closed on April 29, 2026.

Key Legal Developments and Outcome:

1. Filing & Initial Pleadings:

• Complaint Filed (2024-05-22): Inari Medical, Inc. ("Inari") filed a patent infringement lawsuit against Imperative Care, Inc. and Truvic Medical, Inc. ("Imperative Care") in the U.S. District Court for the Northern District of California.
• Parties: Plaintiff is Inari Medical, Inc. Defendants are Imperative Care, Inc. and Truvic Medical, Inc. Imperative Care, Inc. is also listed as a counter-claimant, and Inari Medical, Inc. as a counter-defendant. The case pertains to medical devices used to treat blood clots.

2. Pre-trial Motions of Substance:

• Motion for Preliminary Injunction Denied (2025-09-29): Inari's motion for a preliminary injunction, which sought to halt Imperative Care's sales of competing thrombectomy devices, was denied by Judge Eumi K. Lee. The court found Inari did not demonstrate a likelihood of success on the merits due to serious questions regarding patent validity, and also found no risk of irreparable harm with a nexus to the alleged infringement. The court noted ongoing parallel IPR proceedings as strong circumstantial evidence against a likelihood of success.
• Discovery Dispute (2025-03-14): A joint letter brief was filed concerning Inari's motion to compel the production of materials related to Imperative Care's blood return system. This dispute touched upon U.S. Patent No. 11,969,333, which Inari had asserted. [cite: 7 - previous search]
• Stay Pending IPR Decisions (2026-01-21): The district court litigation was stayed in its entirety pending the outcome of numerous IPR decisions at the PTAB. A joint stipulation to continue this stay was granted, and an upcoming case management conference was vacated. The parties were instructed to file a joint case management statement by April 29, 2026, to update the court on the IPR statuses and to address whether the stay should be extended. [cite: 6 - previous search]

3. Claim Construction (Markman) Outcomes:

• As of September 29, 2025, the court had not yet issued a claim construction order. This is consistent with the subsequent stay of litigation. [cite: 11 - previous search]

4. Discovery Milestones:

• Beyond the discovery dispute over the blood return system mentioned above, specific major discovery milestones are not publicly detailed as having significantly impacted the trajectory of the case prior to the stay and closure.

5. Trial Events, Verdict, and Post-Trial Motions:

• The case did not proceed to trial, verdict, or post-trial motions before its closure.

6. Final Disposition or Present Posture:

• Case Closed (2026-04-29): The district court case 5:24-cv-03117 was marked as "closed" on April 29, 2026. While the specific terms of closure (e.g., settlement, voluntary dismissal) are not detailed in the available public summaries, the closure date aligns with the deadline for the parties' joint case management statement regarding the IPRs, suggesting a resolution influenced by or coinciding with the PTAB proceedings.

7. Parallel PTAB IPR/PGR Proceedings and Their Effect:
Imperative Care, Inc. initiated multiple IPR proceedings challenging the validity of Inari Medical, Inc.'s patents, which influenced the district court litigation.

• IPR2024-01257: Filed by Imperative Care Inc. v. Inari Medical Inc., this IPR was denied institution on February 7, 2025. While related to the district court case, the specific patent challenged in this IPR is not detailed in the available snippets. [cite: 5 - previous search]
• IPR2025-00728: Filed by Imperative Care Inc. v. Inari Medical Inc., challenging U.S. Patent No. 11,844,921. A trial was instituted on October 10, 2025.
• IPR2025-01021: Filed by Imperative Care Inc. v. Inari Medical Inc., challenging U.S. Patent No. 11,969,333. A trial was instituted on December 11, 2025.
• IPR2025-01025: Filed by Imperative Care Inc. v. Inari Medical Inc., challenging U.S. Patent No. 11,974,910. A trial was instituted on December 11, 2025.

The institution of IPR trials on the primary asserted patents (11,844,921, 11,974,910, and 11,969,333) had a direct impact on the district court litigation, leading to a stay of the case pending the outcomes of these PTAB proceedings. This strategy by Imperative Care was successful in delaying the district court case, and the ultimate closure of the district court case suggests a resolution reached while the IPRs were still active. Other IPRs were also filed by Imperative Care against Inari, challenging different patents: IPR2024-01157 (challenging U.S. Patent No. 11,697,011 B2) and IPR2025-00289 (challenging U.S. Patent No. 11,554,005), which was instituted on June 18, 2025. IPR2025-00989 (challenging U.S. Patent No. 11,865,291) was instituted on October 23, 2025. The widespread challenges across multiple patents held by Inari Medical indicate a comprehensive strategy by Imperative Care.

The plaintiff in this case, Inari Medical, Inc., is represented by attorneys from Perkins Coie LLP.

Here is the identified counsel of record for Inari Medical, Inc.:

• Ramsey M. Al-Salam
  • Role: Counsel
  • Firm: Perkins Coie LLP, Seattle, WA and Denver, CO.
  • Experience Note: Al-Salam is noted for his work in intellectual property litigation and represented Inari Medical, Inc. in this case, including in the preliminary injunction proceedings.

Additional attorneys listed on a joint filing as "ATTORNEYS FOR PLAINTIFF INARI MEDICAL, INC." include:

• Daniel Keese
  • Role: Counsel
  • Firm: Perkins Coie LLP, Seattle, WA.

It is important to note that a preliminary injunction motion filed by Inari Medical, Inc. was denied by the court. The case is currently stayed pending the outcome of inter partes reviews (IPRs) at the Patent Trial and Appeal Board (PTAB).

The defendant in case 5:24-cv-03117, Inari Medical, Inc. v. Imperative Care, Inc., et al., is Imperative Care, Inc..

The counsel of record identified for Imperative Care, Inc. is:

• Joshua Jan Stowell
  • Role: Counsel for Imperative Care, Inc. (implied by appearance in court documents).
  • Firm: Knobbe Martens Olson & Bear, LLP (often referred to as Knobbe Martens).
  • Office Location: While specific office location for this case isn't cited, Knobbe Martens has offices across the United States, including in California. Joseph R. Re, another attorney from Knobbe Martens, has represented Imperative Care in this case and his firm profile indicates an Irvine, CA office.
  • Relevant Patent Litigation Experience: Knobbe Martens is a well-known intellectual property law firm with extensive experience in patent litigation, particularly in the medical device sector. Joseph R. Re, a partner at Knobbe Martens, has experience representing medical device manufacturers in patent disputes, including defeating preliminary injunctions and obtaining stays pending inter partes reviews.

It's worth noting that while the case caption initially stated "et al.", later documents specify Imperative Care, Inc. as the defendant. Inari Medical, Inc. acquired LimFlow S.A. in November 2023, and LimFlow's products, such as the LimFlow System, are relevant to medical devices for treating chronic limb-threatening ischemia, which is the field of the asserted patent. However, LimFlow S.A. is not listed as a defendant in this specific case.

Other attorneys from Knobbe Martens may also be involved, as is common in patent litigation. For example, Joseph R. Re from Knobbe Martens is identified as having represented Imperative Care in this case in relation to a motion for a preliminary injunction.

The case has also seen activity related to parallel inter partes review (IPR) proceedings at the Patent Trial and Appeal Board (PTAB), where Imperative Care Inc. has challenged patents held by Inari Medical Inc.