In Edgewell Personal Care Brands, LLC v. Munchkin, Inc., [2020-1203] (May 26, 2021 modifying March 9, 2021, opinion), the Federal Circuit vacated-in-part, reversed-in-part, and remanded the district court’s summary judgement of no infringement of U.S. Patent Nos. 8,899,420 and 6,974,029 on Diaper Genie refills.

The claims of the ‘420 patent were directed to a cassette intended for use in the Diaper Genie. The Federal Circuit noted that a cassette has a clearance that will ensure proper insertion whether a space remains after insertion or not. The Court therefore concluded that the district court erred by adding this limitation into its construction.

The Federal Circuit reasoned: “The clearance limitation is satisfied when the cassette itself is constructed with a clearance. The claim does not require a clearance after insertion; in fact, such a requirement would be at odds with many of the disclosed embodiments and is simply not required by the claims.”

With respect to the claims of the ‘029 patent, the Federal Circuit found that although the district court correctly construed “annular cover” as being a single structure, the district court erred in concluding that Edgewell’s theory of infringement under the doctrine of equivalents vitiates or renders meaningless the “annular cover” claim element. The Federal Circuit explained that vitiation has its clearest application where the accused device contains the antithesis of the claimed structure, but warned that, as it explained in Deere & Co., courts should be cautious not to shortcut this inquiry by identifying a binary choice in which an element is either present or not present.

The determination of equivalence depends not on labels like “vitiation” and “antithesis” but on the proper assessment of the language of the claimed limitation and the substantiality of whatever relevant differences may exist in the accused structure.

Applying these concepts to the facts of this case, the Federal Circuit concluded that the district court erred in evaluating the element as a binary choice between a single-component structure and a multi-component structure rather than evaluating the evidence to determine whether a reasonable juror could find that the accused products perform substantially the same function, in substantially the same way, achieving substantially the same result as the claims.

Because the district court based its grant of summary judgment of noninfringement of the ’420 patent on an erroneous construction, the Federal Circuit vacated that judgment and remanded. Because the district court erred in granting Munchkin summary judgment of noninfringement of the ’029 patent, the Federal Circuit reversed that judgment and remanded.