CAFC Vacated the Lower Court Claim Construction Related to Antibodies and Antibody Fragments

The Court of Appeals for the Federal Circuit, in Baxalta Inc. v. Genentech, Inc., No. 2019-1527, 2020 U.S. App. LEXIS 27320 (Fed. Cir. Aug. 27, 2020), vacated lower court’s claim construction in regards to “antibody” and “antibody fragments” which can be used to treat hemophilia, and remanded for further proceedings. Id. at *2. In doing so, the CAFC examined “specific disclosures” from the written description “all of which do not comport with the district court’s construction.” Id. at *12; see also id. at *13–15. In addition, the CAFC also found that other dependent claims would be incompatible with the lower court’s construction. Id. at *9. Finally, the CAFC found that the standard for prosecution history estoppel was not met when changing “antibody fragment” to “antibody fragment” and weight could not be given to that change. Id. at *15.

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