U.S. District Court for the Northern District of West Virginia; U.S. Court of Appeals for the Federal Circuit; PTAB

The U.S. District Court for the Northern District of West Virginia (N.D. W. Va.) is a federal court within the Fourth Circuit, though patent claims are appealed to the U.S. Court of Appeals for the Federal Circuit. The court maintains four points of holding in Clarksburg, Elkins, Martinsburg, and Wheeling. While not a high-volume patent litigation venue generally, the Northern District of West Virginia has emerged as a specialized center for Biologics Price Competition and Innovation Act (BPCIA) litigation, largely due to the historical presence of major generic and biosimilar manufacturers like Mylan (now Viatris) in the region.

The court's patent docket, particularly concerning biosimilars, has a reputation for actively managing complex, multi-party disputes. This is evidenced by the Judicial Panel on Multidistrict Litigation consolidating several Regeneron biosimilar cases into an MDL in the Northern District of West Virginia. The court has granted preliminary injunctions in significant biosimilar cases, with some of these rulings being affirmed by the Federal Circuit, indicating a thorough approach to initial validity challenges and infringement likelihood in this specialized area. However, the court has also denied preliminary injunctions where plaintiffs failed to establish a likelihood of success on the merits, as seen in a case involving Amgen, which was also affirmed on appeal. The court does not have distinctive local patent rules similar to those found in districts like the Eastern District of Texas or the Northern District of California, instead operating under its general local rules and standing orders.

The court's patent litigation practice is heavily defined by a series of ongoing and recently resolved biosimilar disputes involving Regeneron Pharmaceuticals, Inc. These include cases against Mylan Pharmaceuticals Inc. (which settled in April 2025 after a permanent injunction was secured by Regeneron and appealed), Samsung Bioepis Co., Ltd. (active, with a Federal Circuit affirmance of a preliminary injunction in early 2025), Formycon AG (active, with motions to dismiss or transfer having been filed), Celltrion, Inc. (which settled in October 2025, vacating a prior preliminary injunction), and Sandoz Inc. (which settled in September 2025).

Chief District Judge Thomas S. Kleeh has been a prominent figure in the court's patent litigation, having presided over nearly all biosimilar cases filed in the district, thereby developing significant expertise in BPCIA litigation. His involvement underscores the concentrated nature of patent practice in this district, particularly concerning the evolving biosimilar legal landscape.