The US Court of Appeals for the Federal Circuit addressed a wide array of issues in a long-running dispute over shower curtain technology. The Court provided important guidance on patent claim scope using intrinsic evidence, trademark standing and ownership of the mark in issue, trade dress functionality under TrafFix, and the need for district courts to provide a reviewable explanation when issuing patent infringement summary judgment based on the facts of this case. Focus Products Grp. Int’l, LLC v. Kartri Sales Co., Inc., Case No. 23-1446 (Fed Cir. Sept. 30, 2025) (Moore, Clevenger, Chen, JJ.)
The decade-long dispute started when Focus Products sent a cease-and-desist letter to Kartri Sales and its supplier, Marquis Mills International. The letter asserted patent infringement but was largely ignored. Focus Products then filed suit asserting three utility patents, two trademarks (HOOKLESS® and EZ ON), and unregistered trade dress rights in the appearance of its shower curtains.
Four months after the Supreme Court’s 2017 decision in TC Heartland v. Kraft Foods Group Brands, Kartri raised a venue objection and filed a motion to dismiss or transfer venue. The district court denied the motion, finding it to be unreasonably late, especially considering that Kartri actively conducted litigation after TC Heartland.
The district court construed several disputed claim terms. Based on its constructions, it found no triable issue of fact and granted summary judgment of patent infringement to Focus Products. However, the district court found genuine disputes of material fact regarding trademark and trade dress infringement and ordered a bench trial on those issues.
On the eve of trial, Kartri asserted unclean hands and equitable estoppel defenses. The district court denied these defenses because they were improperly raised for the first time immediately preceding trial.
After a bench trial, the district court held that:
- Focus Products had standing to enforce the unregistered EZ ON mark.
- Kartri infringed the mark and Focus Products’ trade dress, which was determined to be nonfunctional.
- Kartri infringed Focus Products’ HOOKLESS® mark.
Accordingly, the district court awarded lost profits, reasonable royalties, attorneys’ fees, and enhanced damages for willful infringement. Kartri appealed.
The Federal Circuit affirmed the district court’s denial of Kartri’s motion to transfer venue under TC Heartland, finding Kartri’s objection untimely. Kartri waited four months after TC Heartland to raise the issue, during which time discovery had progressed significantly. The Court emphasized that venue objections must be raised seasonably and that continued litigation in the chosen forum may constitute forfeiture.
The Federal Circuit largely reversed the district court’s infringement findings, explaining that the district court erred in its claim construction because Focus Products had disclaimed shower rings with a flat upper edge during prosecution. While an affirmative disclaimer usually originates from the patent applicant, the Court found clear and unmistakable disavowal through the applicant’s acquiescence to the examiner’s species election, claim cancellation, and narrowed claim scope. This disclaimer was reinforced by the prosecution of a related asserted patent, which explicitly claimed the disclaimed feature. A patentee cannot try to reclaim the scope of a previously disclaimed feature.
The Federal Circuit upheld the district court’s claim construction of the term “projecting edge” but vacated the infringement finding, citing insufficient analysis to sustain summary judgment. The Court instructed the district court to clarify the boundary between the rings’ “outer circumference” and any “projecting edge” in the accused products, especially in light of the similarities between the patent’s figures and the accused products.
The Federal Circuit affirmed the district court’s ruling that not only was Kartri’s unclean hands argument untimely raised, but Kartri also failed to allege that Focus Products acted with the requisite specific intent.
The Federal Circuit reversed the trademark infringement ruling related to the EZ ON mark, concluding that Focus Products lacked trademark standing at the time of filing. The Court found that Focus Products did not satisfy its burden to establish trademark standing because the only evidence Focus Products relied on – a 2012 licensing agreement – did not show that Focus Products owned the EZ ON mark at the relevant time. The Court evaluated the 2012 licensing agreement as a whole and concluded that it did not transfer ownership of the mark to Focus Products. The actual assignment occurred years later, in 2021.
The Federal Circuit vacated the HOOKLESS® trademark infringement finding, holding that the district court improperly focused on product similarity rather than mark-to-mark comparison in its likelihood of confusion analysis. The Court remanded for a proper analysis under the eight Polaroid factors, emphasizing the need to assess how the marks are displayed in the purchasing context rather than “as branded on the parties’ respective products.”
The Federal Circuit also vacated the trade dress infringement finding, instructing the district court to perform the functionality analysis required under the Supreme Court’s 2001 TrafFix opinion. The Court noted that the expired utility patent covering similar features was strong evidence of functionality under TrafFix, and that the district court failed to compare the trade dress elements to the patent claims.
Finally, the Federal Circuit vacated the district court’s findings of willful infringement on both patent and trade dress, and the award of attorneys’ fees. While the district court did not abuse its discretion when it found this case exceptional, the district court failed to distinguish between work on patent infringement versus work on trademark infringement. Accordingly, the Federal Circuit directed the district court to recalculate attorneys’ fees to reflect Focus Products’ revised prevailing party status.
