Federal Circuit Holds that the Markush Group Recitation Limits Only the Specific Associated Element and Not the Entire Claim

The Court of Appeals for the Federal Circuit, in Amgen Inc. v. Amneal Pharma LLC., No. 2018-1086, (Fed. Cir. Jan. 7, 2020), reversed the district court’s claim construction, and vacated and remanded the district court’s finding of non-infringement by Amneal’s product, but affirmed the district court’s judgment that Piramal does not infringe claim 1 of the ‘405 patent and that Zydus infringes claim 1 of the ‘405 patent. The Court held that the district court improperly excluded formulations with additional unlisted ingredients, as a result of an erroneous claim construction of the Markush group.

The full opinion is accessible via http://www.cafc.uscourts.gov/sites/default/files/opinions-orders/18-2414.Opinion.1-7-2020.pdf