Bowman argued that the doctrine of patent exhaustion applies: similar to the copyright "first sale" doctrine, once a patented article is first sold, the patent owner loses further rights with respect to that item. According to Bowman, since the beans were sold to the grain elevator, he can purchase and replant them freely, right?
Not so, says a unanimous Supreme Court: "Under the patent exhaustion doctrine, Bowman could resell the patented soybeans he purchased from the grain elevator; so too he could consume the beans himself or feed them to his animals. Monsanto, although the patent holder, would have no business interfering in those uses of Roundup Ready beans. But the exhaustion doctrine does not enable Bowman to make additional patented soybeans without Monsanto’s permission (either express or implied).""
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