Hazeltine Corporation v. Zenith Radio Corporation

TREANOR, Circuit Judge.

This is an appeal by the plaintiff-appellant, Hazeltine Corporation, from a decree of the United States District Court for the Northern District of Illinois, Eastern Division. Plaintiff began suit in the District Court by a bill of complaint which charged the defendant, Zenith Radio Corporation, with the infringement of one of plaintiff’s patents. In addition to its answer the defendant filed a counter claim in which it pleaded that it had an equitable license under various letters patent, including the patent in question, but that the plaintiff had failed to issue to…