Exhaustion Doctrine
The exhaustion doctrine, also referred to as the first sale doctrine, is a common law patent doctrine that limits the extent to which patent holders can control an individual article of a patented product after an authorized sale. Under the doctrine, once an unrestricted, authorized sale of a patented article occurs, the patent holder’s exclusive rights to control the use and sale of that article are exhausted, and the purchaser is free to use or resell that article without further restraint from patent law.