In the case of Western Electrical Supply Company v. Abbeville Electric Light and Power Company in 1904, the Supreme Court dealt with a dispute over patent rights for electrical equipment. The Western Electrical Supply Company had sold certain patented items to the city of Abbeville's electric company under an agreement that they would not be used elsewhere. However, when these items were subsequently transferred to another party without their consent, Western sued for infringement on its exclusive right to sell within specified territories. The court ruled in favor of Abbeville Electric Light and Power Company stating that once a patented item is lawfully sold, any restrictions imposed by the seller regarding where or how it may be resold are unenforceable as per doctrine of first sale or exhaustion doctrine which limits intellectual property rights after initial sale. This ruling affirmed that patent holders cannot control post-sale use or disposition of a product through contractual agreements.

The dissenting opinion in the case of Western Electrical Supply Company v. Abbeville Electric Light and Power Company argued that the court majority erred in its interpretation of patent law, particularly regarding infringement and validity. The dissent emphasized that a patent is presumed to be valid until proven otherwise, with the burden of proof resting on those challenging it. They contended that this presumption was not adequately considered by the majority. Furthermore, they disagreed with how evidence was evaluated concerning alleged prior use of patented technology; arguing there wasn't sufficient proof to establish such claims conclusively. In their view, any doubts should have been resolved in favor of upholding patent rights rather than invalidating them based on questionable evidence or interpretations.