Yes. In 1980, the US Supreme Court ruled in Diamond v. Chakrabarty that genetically altered life can be patented.
Anyone who buys GM seeds typically has to abide by certain restrictions. For instance, farmers who buy soybeans that have been modified to be resistant to Roundup herbicide sign an agreement saying they will use the seeds for only one planting and won’t save the seeds from the beans they grow for a second planting.
The companies argue that patents are necessary to spur innovation. Critics argue that the patent system has given seed companies disproportionate market power over GM crops — the 10 biggest seed companies now control roughly 73 percent of the industry.