The Supreme Court has declined to hear Merck’s final appeal seeking reinstatement of a $2.5 billion patent verdict against Gilead Sciences.

Merck and its subsidiary Idenix Pharmaceuticals sued Gilead in 2013, alleging that the company’s blockbuster hepatitis C drugs, Sovaldi (sofosbuvir) and Harvoni (ledipasvir/sofosbuvir), infringed on a patent Idenix had for treating hepatitis C.

In December 2016, in the country’s largest ever judgment for patent infringement, a jury in the U.S. District Court for the District of Delaware ordered Gilead to pay Merck $2.5 billion. But a federal judge overturned the verdict in early 2018.

Merck appealed to the U.S. Court of Appeals for the Federal Circuit, which in late 2019 refused to restore the verdict against Gilead. With the Supreme Court’s denial, Merck has now reached the end of the road in the case.