Court of Appeals for the Federal Circuit September 23, 2003, 03-1074, 03-1075, 03-1085, 03-1086 (Ak Steel Corporation v. Sollac and Ugine, Defendants-Cross)

Opinion for the court filed by Circuit Judge LOURIE. Concurring opinion filed by Circuit Judge RADER. AK Steel Corporation appeals from the decision of the United States District Court for the Southern District of Ohio granting summary judgment that its U.S. Patent 4,800,135 was not infringed by Sol-lac and Ugine (collectively, “Sollac”) and that certain claims of its U.S.