Imperative Care Inc v. Inari Medical Inc

1. Case Identification

• Case #: IPR2026-00169
• Patent #: 12,156,669
• Filed: December 16, 2025
• Petitioner(s): Imperative Care, Inc.
• Patent Owner(s): Inari Medical, Inc.
• Challenged Claims: 1-5, 8, 10-12, 14-19, 22, and 24-28, 30

2. Patent Overview

• Title: Aspiration System for Clot Removal
• Brief Description: The ’669 patent discloses a retrieval system for engaging and removing clot material from a blood vessel. The system comprises an aspiration catheter, a vacuum source, a filter chamber, a flow controller, and a hemostasis valve to facilitate thrombectomy procedures.

3. Grounds for Unpatentability

Ground 1: Obviousness over Garrison - Claims 1-5, 8, 10-11, 14-19, 22, 24-25, 30 are obvious over Garrison

• Prior Art Relied Upon: Garrison (Application # 2015/0173782).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Garrison, a prior-art application describing an aspiration system for removing unwanted material from vasculature, discloses all elements of the challenged claims. This includes a vacuum source (e.g., a syringe or pump), an aspiration catheter, a filter chamber with a housing and filter, a flow controller (valve or stopcock), and a hemostasis valve at the catheter's proximal hub. Petitioner asserted that Garrison’s figures and text show these components arranged as claimed, fluidically coupled along a primary fluid path.
  • Motivation to Combine (for §103 grounds): While some claims are challenged as anticipated under 35 U.S.C. §102, Petitioner argued in the alternative that any minor missing details, such as the specific port/connector configuration on the filter or the removability of the filter, would have been obvious modifications. For instance, a person of ordinary skill in the art (POSITA) would have been motivated to use conventional connectors (e.g., Luer fittings) to couple the filter for modularity and compatibility, and would have made the filter removable to allow for cleaning, sample retrieval, or replacement.
  • Expectation of Success: A POSITA would have a high expectation of success as these modifications involved using well-known, standard components for their intended purposes in a predictable manner.

Ground 2: Obviousness over Garrison and Goff - Claims 1-5, 8, 10-11, 14-19, 22, 24-25, 30 are obvious over Garrison in view of Goff

• Prior Art Relied Upon: Garrison (Application # 2015/0173782), Goff (WO 2006/124307).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner contended that to the extent Garrison does not explicitly detail the claimed "filter chamber," Goff discloses the missing features. Goff describes a thrombectomy filter assembly with a housing, an internal filter element, an upper port for connecting to a catheter, and a lower fluid connector for connecting to a vacuum source. Goff explicitly teaches that its filter is removable to permit easy observation and removal of captured clot material.
  • Motivation to Combine: A POSITA would combine Goff’s filter with Garrison’s system as a simple substitution of one known element for another to achieve a predictable result. Both filters serve the identical purpose of filtering clots from aspirated blood and are placed in the same location between the catheter and vacuum source. The motivation would be to incorporate Goff’s well-defined, removable filter design to improve the convenience and functionality of Garrison's system.
  • Expectation of Success: A POSITA would reasonably expect success because combining the components was a straightforward integration of compatible, conventional medical devices.

Ground 3: Obviousness over Garrison, Schaffer, and Hartley - Claims 12, 26-28 are obvious over Garrison in view of Schaffer and optionally Hartley

• Prior Art Relied Upon: Garrison (Application # 2015/0173782), Schaffer (Application # 2003/0225379), and Hartley (Application # 2003/0116731).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground addressed dependent claims reciting specific features of a hemostasis valve. Petitioner argued Schaffer discloses a hemostasis valve with the key claimed features: a flexible tubular member, spring-loaded actuator buttons, and a filament (disclosed as U-shaped actuating members) coupled to the buttons and tubular member. Pressing the buttons loosens the filament to open the valve, and releasing them allows the springs to bias the buttons back, tightening the filament to seal the valve. If Schaffer’s actuating members are not considered a "filament," Petitioner argued Hartley discloses an equivalent structure using a string filament that constricts a tubular diaphragm.
  • Motivation to Combine: A POSITA would be motivated to use Schaffer’s valve (with or without modification from Hartley) in Garrison’s system because Garrison expressly calls for a hemostasis valve but does not detail its internal mechanics. Schaffer provides a known, effective, and adjustable-opening valve designed for use with catheters, fitting the exact need described in Garrison. The combination would yield the predictable result of minimizing blood loss, as intended by both references.
  • Expectation of Success: Success was expected as it involved incorporating a known type of valve into a system designed to use such a valve.
• Additional Grounds: Petitioner asserted additional obviousness challenges based on Garrison (optionally with Goff) in view of Brady (WO 2018/019829) or Pons (Patent 11,432,835) to explicitly teach a vacuum source comprising a "vacuum chamber."

4. Key Claim Construction Positions

• "filament": Petitioner argued this term, central to claims 12 and 26-28, should be construed as "one or more threads, lines, cords, ropes, ribbons, flat wires, sheets, or tapes." This construction is based on intrinsic evidence, including a provisional application incorporated by reference in the ’669 patent, and is broad enough to encompass the U-shaped actuating members of Schaffer or the string of Hartley. Petitioner contended this construction was consistent with the Board's preliminary findings in related IPRs.

5. Arguments Regarding Discretionary Denial

• Petitioner provided a Sotera stipulation, stating that if the Board institutes review, Petitioner will not pursue in district court the grounds asserted in the Petition or any other ground that could have been reasonably raised in the IPR. Petitioner argued this stipulation resolves any potential concerns under Apple v. Fintiv regarding overlapping issues with the parallel district court litigation, which is currently stayed.

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-5, 8, 10-12, 14-19, 22, and 24-28, 30 of the ’669 patent as unpatentable.