The U.S. Supreme Court case Kessler v. Eldred in 1906 revolved around a patent dispute between two manufacturers of cigar lighters, George B. Selden and Henry Ford. The court ruled that once a product has been sold without restriction by the owner of the patent, it is no longer within the control or protection of the patent laws; this principle became known as "patent exhaustion" or "first sale doctrine". This means that after an unrestricted sale, any use or resale by the purchaser is not considered infringement on the rights of the patent holder because those rights have been exhausted with respect to that item. In this particular case, Kessler had previously won a lawsuit against Eldred for infringing his patented design for cigar lighters but later found out Eldred was still selling similar products despite losing in court earlier. However, since these were items already sold before their first legal battle and there was no restriction placed on them at time of sale (i.e., they were part of an unrestricted first sale), Kessler could not sue again for infringement based on these items under principles established by 'first-sale doctrine'.

In the dissenting opinion for Kessler v. Eldred, it was argued that the majority's decision failed to consider important aspects of patent law and its implications on competition. The dissent emphasized that a patent gives an inventor exclusive rights over their invention, not a monopoly in the market where similar or identical products may exist due to independent creation. They contended that once a product is sold, any patented feature becomes public property and can be used by anyone without infringing upon the original patent holder’s rights. Therefore, if two inventors independently create similar products but one secures a later-expiring patent than another who has already sold his product publicly; this should not prevent the first from continuing to sell his own invention after expiration of second’s earlier-granted patents as per majority ruling.