In the case of American Steel Foundries v. Robertson, Commissioner of Patents, and Simplex Electric Heating Company (1922), the Supreme Court was asked to determine whether a patent for an electric furnace should be granted to William E. Robertson or the Simplex Electric Heating Company. The court ruled in favor of Robertson, stating that he had invented a new and useful improvement in electric furnaces which qualified him for a patent under U.S law. The decision hinged on two key points: firstly, that there was no evidence proving prior use or knowledge of such an invention before his application; secondly, that even though some elements were already known within the industry at large they were used by him in a novel way creating something unique enough to warrant protection under patent laws.

In the dissenting opinion for American Steel Foundries v. Robertson, Commissioner of Patents, and Simplex Electric Heating Company (1922), it was argued that the patent in question should not have been invalidated. The dissenting justices believed that there were substantial differences between the patented device and its predecessors which warranted protection under patent law. They disagreed with the majority's view that these differences were merely obvious or trivial modifications to existing technology. Furthermore, they pointed out that this invention had met a long-felt need in industry and had achieved commercial success - factors traditionally considered as evidence of inventiveness by courts. Therefore, according to them, it was unjustified to deny patent protection based on an overly rigid application of legal standards without considering practical realities.