A federal judge has overturned a jury’s 2016 verdict requiring hepatitis C virus (HCV) drugmaker Gilead Sciences to pay a record-breaking $2.54 billion over allegations that the company’s formulas for Sovaldi (sofosbuvir) and Harvoni (sofosbuvir/ledipasvir) infringed on a patent held by rival Merck. & Co., Reuters reports.

U.S. District Judge Leonard Stark, of Wilmington, Delaware, ruled late last week that Merck’s patent was invalid, overturning the largest U.S. patent case ever filed. Stark reasoned that Merck did not meet a requirement that it disclose how to make the treatment it covered without undue experimentation.

This officially overturns a 2016 trial verdict in which jurors found that Merck’s patent on the hepatitis C treatment, which Gilead acquired in 2014 when it bought Idenix Pharmaceuticals, was valid. Idenix, the original holder of the patent at issue in the lawsuit also sued Gilead back in 2013 in an effort to block the company’s launch of Sovaldi but did not win.

In response, a Gilead spokesperson said in a statement that the company always believed the patent was invalid and was pleased that the judge confirmed its position. For its part, Merck issued a statement saying it planned to appeal the case and that the judge’s ruling did not reflect the facts.