In the case of Powers-Kennedy Contracting Corporation et al. v. Concrete Mixing and Conveying Company, 1930, the Supreme Court was asked to determine whether a patent for a concrete mixer had been infringed upon by another company's product. The plaintiff, Concrete Mixing and Conveying Co., alleged that Powers-Kennedy Contracting Corp.'s machine violated their patent rights because it used similar mechanisms in its design as those described in their own patented invention. However, the defendant argued that they did not infringe on any patents since their device functioned differently from what was outlined in the plaintiff’s patent claim. The court ruled in favor of Powers-Kennedy Contracting Corporation stating that while there were similarities between both machines' designs; these resemblances were superficial and did not constitute an infringement on Concrete Mixing's patent rights. The court emphasized that it is not merely similarity but identity or equivalence which constitutes infringement under U.S law.

The dissenting opinion in the case of Powers-Kennedy Contracting Corporation et al. v. Concrete Mixing and Conveying Company argued that the majority's decision to uphold a patent infringement claim was incorrect because it failed to consider whether or not there had been any actual copying by the defendants, which is an essential element of patent infringement cases. The dissent also disagreed with the majority's interpretation of what constitutes a "new" invention under patent law, arguing that merely combining existing technologies in a new way does not necessarily constitute inventiveness worthy of legal protection. Furthermore, they contended that even if such combination could be considered inventive, this particular combination was obvious and therefore unpatentable under established precedents.