Kaken Pharmaceutical Co., Ltd. v. Iancu, No. 18-2232 (Fed. Cir. 2020)Annotate this Case
Kaken’s patent, titled “Method For Treating Onychomycosis,” describes and claims methods for topically treating fungal infections in human nails. On inter partes review under 35 U.S.C. 311–319, the Patent Trial and Appeal Board determined that all claims of the patent are unpatentable for obviousness. The Federal Circuit vacated. The Board erred in its claim construction of one claim limitation--“treating a subject having onychomycosis.” Kaken’s unambiguous statement that onychomycosis affects the nail plate, and the examiner’s concomitant action based on this statement, make clear that “treating onychomycosis” requires penetrating the nail plate to treat an infection inside the nail plate or in the nail bed under it. The Board’s obviousness analysis materially relied on its erroneous claim construction.