This week, the Supreme Court began hearing oral arguments for Life Technologies v. Promega, in which the high court will determine whether a U.S. patent can still be infringed upon if a “substantial portion” of the product’s components are assembled abroad.

According to an Ars Technica report, Life Technologies and Promega are competitors in the DNA test kit industry. At one point, Promega licensed several of its patents to one of Life Tech’s brands, Applied Biosystems. The license did not permit the kit to be sold for clinical or research purposes. In 2010, Promega filed a lawsuit against Applied Biosystems, alleging the company had infringed on its patents by intentionally selling the kits in unlicensed fields.

While a Wisconsin federal jury found that Applied Biosystems was liable to the tune of $52 million, the judge set aside that verdict because almost all — four-fifths or 80 percent to exact — of the product was assembled and shipped from outside of the United States. The judge believed that the one-fifth or 20 percent that was assembled and shipped from the United States did not constitute “all or a substantial portion” of the DNA test kit.

When Promega appealed the case to the U.S. Court of Appeals for the Federal Circuit, the split panel of judges interpreted “substantial” as “important” and ruled that the lone fifth component — Taq polymerase — assembled in the United States was essential and that the kit was inoperable without it.

Now Life Tech has brought the case before the Supreme Court, contending that the Federal Circuit was mistaken in extending the U.S. patent laws abroad.