What License Governs the WebM Video Format?

This article provides a comprehensive overview of the licensing structure behind the WebM media file format. It explores the open-source nature of WebM, the specific licenses governing its primary video codecs (VP8, VP9, and AV1) and audio codecs (Vorbis and Opus), and how Google’s patent grant ensures it remains free for public and commercial use.

The Core License: Creative Commons and BSD

The WebM format itself is an open, royalty-free media file format designed specifically for the web. Google released the WebM project structure under a Creative Commons Attribution 3.0 Unported License, while the software source code for the development tools is distributed under a BSD-style license. This combination allows developers, creators, and businesses to use, modify, and distribute the format without paying royalties or licensing fees.

Codec-Specific Licensing

Because WebM is a container format based on a profile of Matroska (MKV), its licensing is also tied directly to the specific video and audio codecs it encapsulates.

Video Codecs (VP8 and VP9)

Originally developed by On2 Technologies and later acquired by Google, the VP8 and VP9 video codecs are the backbone of the WebM format. Google released these codecs under a BSD-style software license. Crucially, this release includes a worldwide, non-exclusive, no-charge, royalty-free, irrevocable patent license, allowing anyone to use the video technologies in their software and hardware implementations.

Audio Codecs (Vorbis and Opus)

WebM files utilize Vorbis or Opus for their audio streams.

• Vorbis: Governed by a three-clause BSD license, making it completely free for both personal and commercial use.
• Opus: Governed by a three-clause BSD license as well, accompanied by a complementary, royalty-free patent grant from Xiph.Org, Microsoft, Skype, and Broadcom.

The WebM Patent Grant and Commercial Use

The defining feature of the WebM license is its explicit protection against patent litigation. Google provides a free patent license to any user, but this grant contains a termination clause: if a user or company files a patent infringement lawsuit alleging that VP8 or VP9 infringes on their own patents, their rights to the WebM patent license are immediately revoked. This legal mechanism safeguards the open-source community and ensures WebM remains a viable, royalty-free alternative to restrictive, paid formats like H.264 and H.265.