Digest of Tristrata, Inc. v. Microsoft Corporation, No. 2014-1168 (Fed. Cir. Dec. 4, 2014) (nonprecedential). On appeal from N.D. Cal. Before Lourie, Schall, and Dyk.
Procedural Posture: TriStrata appeals a stipulated judgment of non-infringement of two of its patents related to encrypting electronic documents, following the court’s construction of five disputed terms. CAFC affirmed.
- Claim construction: The district court correctly construed the term “seal” (the only disputed term on appeal) as it is disclosed in the claims and the written description of the invention, rejecting a general-use dictionary definition of “seal.” CAFC rejected TriStrata’s interpretation of the Thorner case as “requiring an ordinary dictionary definition absent clear lexicography or manifest disavowal of claim scope.” The written description should be examined before relying on extrinsic evidence, since doing so “mitigates the risk of ‘transforming the meaning of the claim term to the artisan into the meaning of the term in the abstract, out of its particular context.’”