Court of Appeals for the Federal Circuit September 7, 1999, 99-1041 (Atlas Powder Company, and Hanex Products, Inc. v. Ireco Incorporated and Ici Explosives Usa, Inc.)

RADER, Circuit Judge.

The United States District Court for the District of Wyoming determined that U.S. Patent No. 4,111,727 (the Clay patent) and its reissue, U.S. Patent No. RE 33,788 (the reissue patent) were invalid. Atlas Powder Company (Atlas), a licensee under those patents, sued IRECO Incorporated (IRECO) for infringement of the Clay patent.