On Sep. 03, 2021, Federal Circuit affirmed Delaware district court’s claim construction and thus infringement ruling in a Hatch-Waxman litigation.

Previously, Bristol-Myers Squibb / Pfizer Inc. (Plaintiffs) sued Sigmapharm Laboratories, Sunshine Lake Pharma and Unichem Laboratories (Defendants) for infringement of US 6,967,208 (compound patent – expiring on 11/21/2026) and US 9,326,945 (composition patent – expiring on 02/24/2031). The main issues were with respect to certain terms appearing in US’208 & US’945 patent. Delaware court construed these terms in favor of plaintiffs and found infringement on Aug. 05, 2020. You can read the detailed summary “here“.

During appeal, Federal Circuit affirmed Delaware court’s construction of these terms and found no clear error. And since infringement and invalidity determination flow directly from claim construction, Federal Circuit affirmed.