Servo Corporation of America v. General Electric Company

WINTER, Circuit Judge:

As more particularly set out in Servo Corporation of America v. General Electric Company, 337 F.2d 716 (4 Cir. 1964), we held U. S. Patents Nos. 2,880,309 and 2,903,575, of which Servo was the assignee, invalid and, hence, incapable of infringement by General Electric. The patents were for devices known as “hot box detectors,” useful in the railroad industry to detect an abnormal quantity of heat emanating from freight car journal boxes. At the same time, we concluded that General Electric had been unjustly enriched by its wilful copying of Servo’s device, purportedly…