The Federal Circuit’s recent decision in Focus Products Group Int’l, LLC v. Kartri Sales Co., 156 F.4th 1259 (Fed. Cir. 2025), serves as an important reminder that what patent applicants say and do not say during prosecution can carry lasting consequences, including when responding to procedural actions like restriction requirements. The case underscores the need for disciplined drafting and deliberate strategy throughout prosecution.
The patent at issue related to a hookless shower curtain and included claims broadly drafted to a curtain “ring” with additional features. Although the district court construed the claimed “ring” broadly, the Federal Circuit held that prosecution conduct following an early restriction requirement limited “ring” to exclude a ring with a flat upper edge. Specifically, after the patentee elected a species, the examiner withdrew and eventually cancelled a claim expressly covering a ring with a flat upper edge, claiming it was drawn to a nonelected species. At no point did the patentee dispute the examiner’s characterization of the elected claim scope. And because the defendants’ product used rings with a flat upper edge, the Court reversed the infringement finding.
Although this case turned on repeated silence in the face of the examiner’s characterizations, this decision elevates the importance of how applicants respond to restriction requirements in utility patent applications. Accordingly, applicants should ensure their practices align with this guidance. When electing a species, applicants should consider including an explanation of their disagreement to create a record that indicates claim scope was not disavowed through election. Additionally, applicants should consider filing divisional applications to pursue nonelected species to secure claims capturing the full scope of the invention in case the restriction and election is later found limiting.
