Gilead and Merck in patent litigation over rights to Sovaldi (sofosbuvir) and Harvoni (ledipasvir + sofosbuvir)

Gilead Sciences brought action to invalidate two Merck patents in August 2013 after Merck demanded a 10% royalty on sales of Sovaldi and its combinations, including Harvoni. Merck filed a counterclaim alleging infringement of the Merck patents. A Northern District Court of California has, by a jury, upheld the Merck patents. If the jury grants damages equal to Merck's demand for a 10% royalty, Gilead could owe Merck almost $2 billion based on 2015 sales of Sovaldi and Harvoni. Gilead will appeal as it alleges that the Merck patents are too broad and will seek a judge trial rather than a jury. Indenix Pharma acquired by Merck in 2014 filed against Gilead in a patent case in the US and UK but the court found for Gilead.