Obviousness

The obviousness of US patent 11406402 under 35 U.S.C. § 103 has been extensively litigated through Inter Partes Review (IPR) IPR2024-01261 at the Patent Trial and Appeal Board (PTAB), with the decision subsequently affirmed by the Court of Appeals for the Federal Circuit (CAFC) in case 26-1719.

PTAB Findings on Obviousness

In IPR2024-01261, the petitioner, Unified Patents, LLC, challenged claims 1-4, 7-9, 11-12, 14-15, 17-23, 25-31, and 33-46 of US Patent 11406402 on grounds of obviousness under 35 U.S.C. § 103. The PTAB instituted review on all challenged claims on November 8, 2024, finding a reasonable likelihood that the petitioner would prevail on at least one claim.

The Final Written Decision, issued on November 8, 2025, concluded that all challenged claims (1-4, 7-9, 11-12, 14-15, 17-23, 25-31, and 33-46) were unpatentable. The Board determined that Unified Patents, LLC, had demonstrated by a preponderance of the evidence that these claims were obvious in view of various combinations of cited prior art.

Federal Circuit Affirmation

Rapidpulse Inc., the patent owner, appealed the PTAB's decision to the Court of Appeals for the Federal Circuit (CAFC) under docket number 26-1719. The Federal Circuit affirmed the PTAB's Final Written Decision, thereby upholding the unpatentability of claims 1-4, 7-9, 11-12, 14-15, 17-23, 25-31, and 33-46 of US Patent 11406402.

Specific Prior Art References and Motivation (as determined by PTAB and affirmed by CAFC)

While the provided patent text and litigation summary do not explicitly list the specific prior art references relied upon by the PTAB and the Federal Circuit in their decisions, they clearly indicate that the unpatentability was based on combinations of prior art references rendering the claims obvious.

A person having ordinary skill in the art (POSA) at the time of the invention (with a priority date of 2018-07-20) would have been motivated to combine existing technologies to address known problems in aspiration thrombectomy. The "Prior art keywords" associated with the patent – "vacuum," "catheter," "vent," "valve," and "controller" – suggest the general technological landscape in which such a POSA would operate.

The motivation to combine existing elements from the prior art to achieve the claimed invention would typically stem from:

• Addressing known problems in the field: The patent itself highlights significant disadvantages of current thrombus removal devices, such as the inability to ascertain thrombus capture/removal without full withdrawal, the issue of clots being larger than catheters and "corking," and the desire to increase first-pass recanalization rates. Prior art in thrombectomy would reveal these same challenges.
• Improving existing systems: A POSA would seek to improve the efficiency, safety, and effectiveness of aspiration thrombectomy. For example, systems that employ a "vacuum interruption controller" (as described in claim 1) to dislodge a "corked" thrombus, or a "vacuum and vent control system" (as described in claims 5, 10, 13, 16, 24, and 32) to cyclically change vacuum levels while preventing forward flow, would represent solutions to known limitations.
• Leveraging established principles: The components mentioned in the claims (catheters, vacuum pumps, vent valves, vacuum valves, and controllers) are fundamental to fluid control and medical device design. A POSA would be aware of various techniques for controlling vacuum and fluid flow, including pulsatile or intermittent vacuum applications, and the use of vents for pressure modulation.
• Routine design choices: Integrating control mechanisms, such as mechanical or electronic valve controllers, or automated systems that recognize catheter parameters (as in claims 24 and 32), would be considered routine design optimization for improving user experience and device performance in medical applications.

While the precise combinations and their detailed rationales are not available in the provided text, the PTAB and CAFC decisions confirm that the claimed inventions, encompassing features like cyclic vacuum and vent control to prevent forward flow and automatic parameter recognition, were indeed considered obvious to a POSA when considering the existing body of prior art in the field of aspiration thrombectomy. As a result, claims 1-4, 7-9, 11-12, 14-15, 17-23, 25-31, and 33-46 have been deemed unpatentable.