Shenzhen Kelaisiman Seeks a Declaratory Judgment on a Hyperice Percussion Massager Patent After an APEX Assertion.

The parties and the court

The case is Shenzhen Kelaisiman Trading Co., Ltd. v. Hyperice IP Subco, LLC, No. 2:26-cv-03686 (W.D. Wash.), filed September 30, 2026. The docket shows Magistrate Judge Grady J. Leupold added to the case. The plaintiff is a Chinese company based in Shenzhen that operates an Amazon storefront. The complaint alleges, on information and belief, that Hyperice IP Subco is a Delaware limited liability company. Personal jurisdiction and venue are pleaded on the ground that Hyperice invoked Amazon's patent-enforcement process, which the complaint ties to Washington.

The APEX assertion

The complaint alleges that on September 9, 2026 Hyperice executed an Amazon Patent Evaluation Express (APEX) agreement identifying claim 7 of the '082 patent and multiple listings, including the plaintiff's two, and that Amazon notified the plaintiff the next day that the listings would be removed absent resolution, participation in APEX, or a qualifying federal lawsuit.

The patent

U.S. Patent 11,938,082, titled Massage Device Having Variable Stroke Length, issued March 26, 2024. As the complaint quotes it, claim 7 depends from claim 1 and adds a flywheel driven by the motor's output shaft and a crank pin connected to the piston, and claim 1 requires a quick-connect system configured to have the proximal end of a massaging head inserted into or removed from the piston bore while the piston reciprocates. The complaint says the Patent Trial and Appeal Board construed that limitation in a May 11, 2026 final written decision in PGR2025-00013, which it says is on appeal to the Federal Circuit as No. 26-1950.

The counts

Count I seeks a declaratory judgment of noninfringement. The complaint alleges that each accused massager holds its head with an elastic fit ring pressed into the piston bore by interference and friction, designed to be changed with the motor stopped, and so lacks the quick-connect limitation of claim 1 and every claim depending from it; it adds that claim 17 has been statutorily disclaimed and that independent method claim 18 is not performed by selling the products. Count II, pleaded in the alternative, seeks a declaratory judgment that claims including claim 7 are invalid as obvious under 35 U.S.C. 103 over four earlier patents and publications, to the extent Hyperice reads the quick-connect limitation broadly enough to reach a friction fit.

Relief sought

The plaintiff asks for declarations of noninfringement and invalidity, costs, and attorneys' fees under 35 U.S.C. 285 if the case proves exceptional. It demands a jury.

What to watch next

The docket shows a summons issued to Hyperice on September 30, 2026. Watch for service and for Hyperice's answer, motion, or any counterclaim for infringement.