Yet, Dolby’s lawsuit filed in the US District Court for the District of Delaware [PDF] alleges that AV1 leverages technologies that Dolby has patented and has not agreed to license for free and without receiving royalties. The filing reads:
[AOMedia] does not own all patents practiced by implementations of the AV1 codec. Rather, the AV1 specification was developed after many foundational video coding patents had already been filed, and AV1 incorporates technologies that are also present in HEVC. Those technologies are subject to existing third-party patent rights and associated licensing obligations.
Tl;DR