In 1917, the Supreme Court reversed the four-year-old "Henry v. A.B. Dick Co." decision and established patent misuse as an affirmative defense to copyright infringement. In "Motion Picture Patents Co. v. Universal Film Mfg. Co.", the Supreme Court held that requiring a patented film projector only be used for screening films authorized by the patent holder was unenforceable and constituted patent misuse. The Court concluded that the patentee's attempt to extend its monopoly power beyond the rights that the patent statute conferred on it was inequitable, and because of the patentee's "unclean hands," the court, as a court of equity, would not grant it relief. In explaining its ruling, the Court said: