TikTok, the popular short-form video app, has been sued by rival Triller, which accused it of infringing its patent for stitching together multiple music videos with a single audio track.

Triller said in a complaint filed on Wednesday that TikTok and its Chinese-owned parent ByteDance Ltd willfully infringed the June 2017 patent by importing and selling its app for iPhones and Android-based smartphones.