The Supreme Court Wednesday tackled the first of two patent cases it will hear this term that could make it easier for companies to challenge patents in court.

The justices heard oral arguments in a case involving two biotech firms: Gaithersburg, Md.-based MedImmune Inc. and San Francisco-based Genentech Inc. At issue in the dispute is whether a company must stop paying royalties on a patent license to challenge the validity of the patent. MedImmune is paying licensing fees to Genentech for an antibody technology used in MedImmune’s childhood respiratory drug Synagis, while at the same time challenging Genentech’s patent in court.