In the case of Brulotte et al. v. Thys Co., the U.S Supreme Court ruled that a patent holder cannot charge royalties for the use of his invention after its patent has expired. The dispute arose when Thys Co., who held a patent on a hop-picking machine, entered into an agreement with Brulotte to lease several machines in exchange for annual royalty payments extending beyond the expiration date of their patents. When Thys attempted to collect these post-expiration royalties, Brulotte sued arguing such collection was unlawful under existing antitrust and patent laws. The court agreed with Brulotte, holding that any attempt to extend monopoly privileges granted by a patent beyond its statutory term is contrary to public policy as it restricts free competition in ideas which are part of public domain upon expiry of patents.

In the dissenting opinion for Brulotte et al. v. Thys Co., Justice Harlan argued that the majority's decision was based on an overly rigid interpretation of patent law, which failed to consider economic realities and business practices. He contended that a contract extending royalty payments beyond a patent's expiration date should not be automatically deemed unlawful because it could reflect a reasonable amortization of costs or other legitimate business arrangements between parties. The Court’s role, he suggested, should not be to invalidate such agreements outright but rather assess whether they were used as instruments of abuse in restraint of competition - something that wasn't evident in this case according to him.