The US Court of Appeals for the Federal Circuit vacated a preliminary injunction, finding that the district court improperly imported a spatial limitation into the claim term “backplate” and erroneously treated the structural term “pin” as a means-plus-function limitation. The Court also reiterated that in preliminary injunction proceedings, a strong showing of validity and infringement does not give rise to a presumption of irreparable harm. Socket Solutions, LLC v. Import Global, LLC, Case No. 25-1121 (Fed. Cir. Aug. 4, 2026) (Moore, C.J.; Prost, J.; Seeborg, Distr.J. (sitting by designation)).
Socket Solutions owns a patent directed to an indoor electrical outlet cover designed to conceal an outlet’s contact openings while permitting continued use of the outlet. Socket Solutions sued Import Global, alleging that Import Global’s Neat Socket product infringed. Socket Solutions also moved for a preliminary injunction. Adopting a magistrate judge’s reports and recommendations, the district court granted the injunction, barring Import Global from making, using, selling, offering to sell, or importing the accused product. Import Global appealed.
The Federal Circuit first addressed the district court’s construction of “backplate.” The district court construed the term as the component of the cover opposite the frontplate that included at least one set of electrical prongs. Import Global argued that the backplate instead referred to the portion of the cover closest to the wall outlet.
The Federal Circuit rejected both constructions because each imposed a spatial relationship not required by the specification. Looking to the written description, the Court explained that the backplate was used to define the thickness of the outlet cover. The Court therefore construed “backplate” as the component that, together with the frontplate, formed the cover such that the cover’s maximum thickness was measured between the frontplate and that component at the cover’s central portion. The Court also declined to require the backplate itself to include electrical prongs. Because the asserted claim separately recited that limitation, incorporating it into the construction of “backplate” would improperly render other claim language superfluous.
The Federal Circuit next concluded that the district court erred by construing “pin” as a means for making an electrical connection between a wire and a corresponding prong, effectively treating the term as a means-plus-function limitation under Section 112(f). Because the claim did not use the word “means,” the presumption against application of Section 112(f) applied. The Court found that the presumption was not overcome because the specification described a “pin” structurally, and the parties agreed that a skilled artisan would understand a pin to identify structure.
The Federal Circuit rejected Socket Solutions’ proposed purely functional construction as too broad because not every structure capable of connecting a wire to a prong is necessarily a pin. It likewise rejected Import Global’s proposed “mechanical system” construction as unsupported by the specification. Finding neither lexicography nor disavowal, the Court concluded that “pin” should receive its plain and ordinary meaning.
Finally, the Federal Circuit addressed the district court’s irreparable harm analysis. Although the Court did not decide whether Socket Solutions had established irreparable harm, the Court concluded that the district court erred to the extent it relied on a presumption of irreparable harm based on a clear showing of patent validity and infringement.
The Court explained that eBay v. MercExchange requires application of traditional equitable principles when determining whether injunctive relief is warranted, and subsequent Federal Circuit precedent eliminated the former presumption of irreparable harm in patent cases. Although those decisions arose in the permanent injunction context, the Court found no basis for applying a different rule to preliminary injunctions. The Court instructed that on remand, the district court may reconsider irreparable harm without relying on any presumption.
Practice Note: Patent owners seeking preliminary injunctions should develop evidence establishing irreparable harm independent of the strength of their infringement case, such as lost market share, price erosion, or harm to customer relationships and goodwill. This decision also underscores the risks of defining facially structural claim terms solely by the function they perform, particularly where doing so could trigger an unintended Section 112(f) analysis.
