"The basis of the patent exhaustion doctrine is when a patent owner sells a patented product the patent owner can no longer control that item through the patent laws — its patent rights are said to have become exhausted. The purchaser and all subsequent owners are free to use or resell the product just like any other item of personal property, without fear of an infringement lawsuit."

"The two questions about the scope of the patent exhaustion doctrine that were presented in Impression Products v. Lexmark, were: (1) Whether a patentee that sells an item under an express restriction on the purchaser’s right to reuse or resell the product may enforce that restriction through an infringement lawsuit; and (2) Whether a patentee exhausts its patent rights by selling its product outside the United States, where American patent laws do not apply."

"With respect to the first, relating to the Return Program cartridges, the Supreme Court concluded that Lexmark exhausted its patent rights in those cartridges the moment it sold them. The Court further observed that while the singe-use and no-resale restrictions may be perfectly clear and enforceable under contract law principles, they do not entitle Lexmark to retain patent rights in an item it has elected to sell. Once a patent owner sells an item it has enjoyed the rights secured by the limited monopoly[1] provided by the patent, the Court explained citing to Keeler v. Standard Folding Bed Co., 157 U. S. 659, 661 (1895)."