Focus Prods. Grp. Int’l, LLC v. Kartri Sales Co(2)

Authored by: Jeremy J. Gustrowsky

The Federal Circuit’s September 30, 2025 decision in Focus Products Group International, LLC v. Kartri Sales Co. provides important guidance on patent claim interpretation, trademark standing, and trade dress functionality—issues that frequently arise in intellectual property disputes. This case centered on Focus’s “hookless” shower curtain designs, which use embedded rings instead of traditional hooks, and their associated patents, trademarks, and claimed trade dress rights. Focus accused Kartri and Marquis Mills of infringing its patents (U.S. Patent Nos. 6,494,248; 7,296,609; and 8,235,088), trademarks (HOOKLESS® and EZ ON), and trade dress.

A key issue was whether the accused products, which featured rings with flat upper edges, infringed Focus’s patents. The Federal Circuit found that during prosecution of the ‘248 and ‘609 patents, Focus had clearly disavowed coverage of rings with flat upper edges. As a result, the court reversed the district court’s finding of infringement for those patents. However, for the ‘088 patent, the court said the lower court did not sufficiently explain its infringement analysis and sent the issue back for further review.

On the trademark front, the court ruled that Focus lacked standing to assert the EZ ON mark at the time it filed suit, as it did not own the mark then. The court also found that the district court’s analysis of whether Kartri’s use of “hookless” was likely to confuse consumers with the HOOKLESS® mark was incomplete, requiring a more detailed comparison of the marks as actually used in the marketplace.

Finally, the court vacated the trade dress infringement finding, emphasizing that the district court failed to properly apply the Supreme Court’s TrafFix standard for functionality. Because Focus’s expired utility patent claimed features similar to those in its asserted trade dress, the court said Focus bore a heavy burden to show those features were not functional—a burden the district court had not adequately analyzed. The case was sent back for a new trial on several issues, including damages and attorneys’ fees.