The US Supreme Court just ruled today that it is infringement for a farmer to make new copies of seeds that contain patented genetic modifications by harvesting them from older plants. The ruling is a victory for agribusiness giant Monsanto, a US company that holds a patent on soybean seeds with genes that make plants resistant to Monsanto's popular weed killer, Roundup. Monsanto sued a rural Indiana farmer who purchased mixed soybean seeds from a secondary supplier, planted them, then used Roundup to wipe out all the plants that did not contain Monsanto's genetic modifications and saved the resulting new seeds to replant. The Supreme Court's ruling upholds an $84,000 fine against the farmer that was issued by a lower court.

In a unanimous 9-0 ruling, the Supreme Court ruled that the farmer had violated Monsanto's patents and its agreement with customers that they repurchase new versions of the genetically-modified seeds every growing season, rather than harvesting seeds containing the genetic modifications from last season's crops. The Indiana farmer, 75-year-old Hugh Bowman, argued that his actions were legal under the longstanding doctrine of "patent exhaustion," which gives a customer the right to resell a patented item without fear of infringement, so long as he or she purchased it legally in the first place. But the Supreme Court vehemently disagreed: "Patent exhaustion does not permit a farmer to reproduce patented seeds through planting and harvesting without the patent holder’s permission," the Supreme Court said in its decision.