Shenzhen Ruichenxi Says an Amazon Seller Repudiated a Royalty License and Sues It on Two Downspout Extension Design Patents.

The complaint

The case is Shenzhen Ruichenxi Technology Co., Ltd. v. Quanzhou Yongchun Pintuo Trading Co., Ltd., No. 1:26-cv-02959 (W.D. Tex.), a 13-page complaint filed October 20, 2026, in the Austin Division, ECF No. 1. The complaint says both parties are companies organized under the laws of the People's Republic of China and that the plaintiff is based in Shenzhen, Guangdong Province, and designs and sells downspout extension products. It says the defendant operates the Amazon.com storefront "Wu qingquan," which identifies the seller by the pinyin form of the defendant's Chinese name.

Jurisdiction and venue

The complaint pleads subject matter jurisdiction under 28 U.S.C. 1331 and 1338(a), and supplemental jurisdiction over the contract claim under 28 U.S.C. 1367(a). It pleads personal jurisdiction based on sales to Texas through the Amazon storefront, including the plaintiff's own September 23, 2026 purchase of an accused product for delivery to Austin, and in the alternative under Rule 4(k)(2). It pleads venue under 28 U.S.C. 1391(c)(3) because the defendant is not a United States resident.

The design patents

U.S. Design Patent D1,012,250, "Downspout Extension," issued January 23, 2024, and U.S. Design Patent D1,016,252, "Downspout Extension," issued February 27, 2024. The complaint says each claims the ornamental design for a downspout extension, as shown and described: the '250 patent the transition, collar and ribbed connector of the larger adapter, and the '252 patent the same features of the smaller adapter, with the rectangular body and the corrugated pipe shown in broken lines. It alleges that the plaintiff owns both patents by assignment from the named inventor.

The license

The complaint says that on or about January 29, 2024, the plaintiff granted the defendant a nonexclusive license, formed over WeChat, to sell the downspout products offered through the Wu qingquan storefront, at US$1.50 per two-pack and US$2.00 per three-pack, halved each year from mid-October through mid-January. It says the defendant paid royalties of approximately RMB 450,200 from January 2024 through September 2025 and then stopped paying. It alleges that on March 12, 2026, the defendant's principal refused to pay, said the defendant had obtained a patent of its own, and told the plaintiff to sue, and that the plaintiff treats the license as terminated on that date.

The complaint alleges, on information and belief, that the patent the principal referred to is U.S. Design Patent D1,018,797, "Downspout Extension," issued March 19, 2024, naming the defendant as applicant. It says three of the plaintiff's design patents, D988,482, D988,483 and D997,309, are listed among that patent's cited references, and alleges that the '797 patent does not authorize the defendant to sell products embodying the asserted designs, citing 35 U.S.C. 154(a)(1).

The accused products

The complaint accuses Rodnsurw flexible downspout extension kits sold under ASIN B0CGXHSBV7 and six variation ASINs, each with two or three corrugated drainpipes and a larger and a smaller adapter for each. It says that, as of September 2026, Amazon reported more than 2,000 purchases of those listings in the preceding month. It alleges that the plaintiff's own orders from January through September 2026 fell, with several listings down about 20 to 40 percent year over year, and alleges, on information and belief, that the defendant's sales contributed to that decline.

The claims

Counts I and II allege infringement of the '250 and '252 patents under 35 U.S.C. 271(a) since the termination date, comparing figures of each patent with the accused larger and smaller adapters under the ordinary observer test. Each alleges willful infringement because the defendant sold under the license and kept selling after it ended. Count III alleges breach of the license for royalties that accrued before the termination date and, in the alternative, for royalties since then if the license did not terminate.

The relief sought

The prayer asks for a judgment of infringement, preliminary and permanent injunctions under 35 U.S.C. 283, an order to remove or disable the Amazon listings and any other marketplace listings, a sworn compliance report within thirty days, the defendant's total profit under 35 U.S.C. 289 or damages under 35 U.S.C. 284 with an accounting, contract damages including unpaid royalties, a willfulness finding with enhanced damages, attorneys' fees under 35 U.S.C. 285, interest and costs, and other relief. The complaint demands a jury.

What to watch next

Watch for service on the defendant and for any motion for a preliminary injunction.