In Sears, Roebuck & Co. v. Stiffel Co. (1964) 376 U.S. 225, Sears copied one of Stiffel's lamp designs and sold it for considerably less. Consequently, Stiffel filed suit alleging patent infringement under federal law and unfair competition under state law based on the likelihood of confusion among consumers concerning the source of the lamp. ( Id. at pp. 225-226.) The federal district court found the patents to be invalid for lack of invention, but awarded judgment in favor of Stiffel on the unfair competition claim and enjoined Sears from selling the lamps. ( Id. at p. 226.) The Supreme Court reversed, concluding: "Obviously a State could not, consistently with the Supremacy Clause of the Constitution, extend the life of a patent beyond its expiration date or give a patent on an article which lacked the level of invention required for federal patents. To do either would run counter to the policy of Congress of granting patents only to true inventions, and then only for a limited time. Just as the State cannot encroach upon the federal patent laws directly, it cannot, under some other law, such as that forbidding unfair competition, give protection of a kind that clashes with the objectives of the federal patent laws." ( Id. at p. 231.)