Look To Specification To Interpret Facially Unclear Claims

Addressing claim construction issues, the US Court of Appeals for the Federal Circuit reiterated the necessity of reading claims in the context of the written description when they are not clear on their face. Howmedica Osteonics Corp. v. Zimmer, Inc., Case Nos. 15-1232; -1234; -1239 (Fed. Cir., May 12, 2016) (Plager, J).

Howmedica sued three companies for infringing a patent directed to a socket assembly for prosthetic hip implants with claims that required a bearing secured into a shell having a recess and a taper “placed at relative locations such that the effectiveness . . . is maintained.” During claim construction, the defendants argued that the relative location claim language required the recess to be “essentially midway” along the taper, and separately argued that the claims required an additional “sleeve” component. The “essentially midway” position was premised on amendments made during a reexamination that added the “relative location” language to