Today, the Supreme Court is set to begin hearing a case between agrochemical giant Monsanto and a farmer who figured out a way around Monsanto's strict requirement that its customers buy new varieties of its genetically modified soybean seeds every year.

The farmer, 75-year-old Vernon Hugh Bowman, attempted to grow two soybean crops on his farm beginning in 1999. The first crop was Monsanto's patented genetically modified soybeans, which are resistant to the company's weed-killer chemical Roundup. Then Bowman planted another crop using cheaper mixed soybean seeds purchased from a grain elevator, which are usually used for livestock feed and not grown for human consumption.

But many of the seeds Bowman bought from the grain elevator also contained Monsanto's patented genetic modifications, and though the company can't stop farmers from selling their leftover Monsanto seeds to grain elevators, it does have agreements prohibiting its customers from saving its seeds from year to year. Because he acquired Monsanto's seeds through this cheaper resale channel and grew them in the same fashion as seeds bought direct from Monsanto, the company sued Bowman for patent infringement, winning an $84,000 judgment in Indiana district court in 2007. Monsanto has sued hundreds of other small farmers for the same reason, and many have settled, but Bowman's is the first case to be heard by the nation's highest court.

Monsanto has sued hundreds of other small farmers for the same reason

He may be just a small farmer trying to save money, but you may recognize the basic elements of his argument. Bowman's defense is tied to patent exhaustion, a historic doctrine similar to the "first sale" doctrine of copyrighted items, both of which say that rights-holders can't sue once they have completed the initial sale of items containing their intellectual property. In this case, the rights holder is Monsanto, which holds patents on the seed genetics. Monsanto won its district court case because the court found that the grain elevator didn't have the right to sell the seeds in the first place, so patent exhaustion didn't apply.

The patent exhaustion doctrine has stood the test of time in part because most patentable physical goods can't be easily reproduced. Patenting seeds wasn't an issue until companies began genetically modifying and claiming the modifications as intellectual property.

In the Monsanto case, the Supreme Court of the United States is looking to answer two main questions: Did Monsanto lose its right to tell Bowman how to use the seeds he bought from the grain elevator because he bought them secondhand? Or should bioengineered seeds receive a special extension of patent protection because they are "self-replicating"?

should bioengineered seeds receive a special extension of patent protection because they are "self-replicating"?

With Bowman's case just one of two major biotech cases the Supreme Court is due to hear early this year — in April, it will hear a case on the legality of another company's claim to the patent on genetic mutations that lead to ovarian and breast cancers, which an Australian court just ruled to be legal — companies with large intellectual property holdings could have much to gain or lose over microscopically tiny genetic property.