On Tuesday, February 19, the U.S. Supreme Court heard oral arguments on a case that could affect whether or not patent protection ends after a product is sold and used, a case with potential implications on products that are easily reproducible. Specifically, the court will decide who owns the genetically modified offspring of patented genetically modified seeds.

In the case before the justices, Bowman v. Monsanto, the plaintiff, Indiana farmer Vernon Bowman, contends that once the genetically engineered seeds have been bought and planted, he should be able to use second generation seeds without paying extra for them.

The case is being closely watched by the biotechnology industry because it could determine whether or not patent law prevents the reproduction of patented products—not only genetically engineered seeds, but also live vaccines, synthetic cell lines, nucleic acid preparations, and other innovations that can be easily reproduced.

From the beginning of the hearing though, the justices began to challenge Bowman’s attorney, Mark Walters, on the merits of his case. “Why in the world would anybody spend any money to try to improve the seed if as soon as they sold the first one anybody could grow more and have as many of those seeds as they want?” Chief Justice Roberts asked.

Justice Stephen Breyer pointed out that the infringement didn’t actually stem from the second generation seed that Bowman planted, rather the fact that he used that second generation to make a third generation of seed. He could have bought the second generation seed and done anything with it he wanted except make new seed—which is what you do when you plant them.

In 2007, Monsanto found that Bowman’s planted a soybean crop that included plants stemming from its seeds. Monsanto’s genetically modified soybean seed is engineered to withstand the herbicide Roundup Ready, also a Monsanto product. A field sprayed with the herbicide kills all the weeds without harming the crop. Farmers pay a premium to use the seed and sign an agreement saying they will not replant the next generation. Farmers have been willing to pay the premium because the seeds provide much greater yields per acre. Since they were introduced in 1996, about 90 percent of the soybeans grown in the United States are genetically modified.

Bowman had previously bought and planted Monsanto seeds and signed the agreement to not use seeds from the crop. But, instead of buying new seed from Monsanto and paying a premium for them, he bought soybeans from a silo that were meant to be used as animal feed and planted them in them. Although Bowman has said he didn’t knowingly plant GM seed, he was probably aware of the likelihood that many of the seeds would be Monsanto’s as 90 percent of the soybean crop in Indiana contains the patented technology. Monsanto discovered the unlicensed soybean crop and sued for patent infringement. The district court found in favor of Monsanto and awarded it nearly $85,000 in damages.

Bowman appealed the district court’s ruling to the Federal Circuit appeals court, which also found in favor of Monsanto. Bowman is asking the Supreme Court to reverse the decision. It is expected to render its opinion in the case sometime in April.