Smith v. Goodyear Dental Vulcanite Company et al. was a United States Supreme Court case that dealt with the issue of patent infringement. The plaintiff, Smith, was the holder of a patent for a process of manufacturing vulcanite, a type of rubber. The defendants, Goodyear Dental Vulcanite Company and others, were accused of infringing on Smith's patent by using the same process to manufacture vulcanite. The Supreme Court held that the defendants had indeed infringed on Smith's patent. The Court found that the defendants had used the same process as Smith, and that the process was not in the public domain. The Court also found that the defendants had not made any changes to the process that would make it distinct from Smith's patent. As a result, the Court held that the defendants had infringed on Smith's patent and ordered them to pay damages. The decision in Smith v. Goodyear Dental Vulcanite Company et al. established that patent infringement occurs when a person or company uses a process that is protected by a patent, even if the process has been slightly modified. This decision has been cited in numerous subsequent cases and has become an important precedent in patent law.

Justice Field delivered the dissenting opinion in Smith v. Goodyear Dental Vulcanite Company et al., arguing that the Court should not have reversed the decision of the Circuit Court. He argued that, under existing law, a patentee was entitled to an injunction against infringement and damages for any past infringements as long as they were within two years prior to filing suit. The majority had held that this rule did not apply when there was no proof of actual damage or loss suffered by reason of such infringement; however, Justice Field disagreed with this interpretation and argued instead that it would be wrong to deny relief simply because there was no evidence of actual harm caused by infringing activities. Furthermore, he noted that Congress had never intended for patents to be so limited in their scope and protection from infringement; thus, he concluded his dissent by stating: "The right secured is one which cannot be denied without doing violence both to language and principle."