In the case of Standard Parts Company v. Peck, the United States Supreme Court ruled on a dispute involving patent rights. The plaintiff, Standard Parts Company, claimed that it held exclusive rights to manufacture and sell certain automobile parts based on patents it owned. It accused the defendant, Mr. Peck, of infringing upon these patents by producing similar parts without permission or license from them. The court found in favor of Mr. Peck after examining evidence presented by both parties which showed that several other companies had been manufacturing identical or very similar parts for years before Standard Parts Company obtained its patents. Therefore, since these designs were already in public use prior to their patent application date they could not be considered new inventions under U.S law and thus were ineligible for patent protection. This ruling affirmed an important principle within American intellectual property law: In order for an invention to qualify for a patent it must truly be novel; if others have previously made or used something equivalent then no one can claim exclusive rights over it through obtaining a later dated patent.

In the dissenting opinion for Standard Parts Company v. Peck, it was argued that the majority's decision to uphold a state law imposing an excise tax on foreign corporations doing business within its borders violated both due process and equal protection clauses of the Fourteenth Amendment. The dissenting justices believed that this type of taxation unfairly discriminated against out-of-state businesses by subjecting them to additional financial burdens not imposed on in-state companies. They also contended that such discriminatory treatment could potentially discourage interstate commerce and undermine national economic unity. Furthermore, they expressed concerns about potential retaliation from other states which might impose similar taxes on their own resident corporations operating elsewhere as a form of retribution or protectionism.