Petitioners brought suit in a federal court to enjoin the respondents from publicly producing a play, alleging that it infringed a copyrighted play of the petitioners and that it would also constitute unfair competition. The parties were citizens of the same State. After considering the claim of infringement on its merits, the court held that, although there was no infringement threatened, the jurisdiction acquired by reason of that federal question might be retained to consider the issue of unfair competition. Hurn v. Oursler, 289 U.S. 238, 53 Sup. Ct. 586 (1933).