VP8 cross-license draft compatible with FOSS licensing

By Aaron Williamson | May 29, 2013

Google recently disclosed a draft cross-license under which patents related to the VP8 video compression format—held by Google, MPEG-LA, and several other companies—would be licensed to the general public. SFLC reviewed these terms and considered some criticisms that have arisen in the free software community. Our opinion expressed here is ours alone, and does not necessarily reflect the position of any client of SFLC.1

Compatibility with Open Source and Free Software Definitions

It has been suggested that the proposed license is incompatible with Open Source Initiative’s Open Source Definition and the Free Software Foundation’s Free Software Definition, the documents that define which terms are appropriate in free and open source copyright licenses. But the VP8 license is not a FOSS license,2 and these definitions’ criteria apply only indirectly to third-party patent licenses.

Critics focus on two provisions in particular: §2, which requires would-be licensees to explicitly accept the license terms, and §3, which limits the license’s “field of use” to implementations of VP8. Both would be unacceptable in a FOSS copyright license on software, but in the context of this particular free-standing third-party patent license, neither provision interferes with FOSS licensing or the freedoms it protects.

Should the developers of a FOSS VP8 implementation accept this license, they would not be required to pass on any restrictions limiting users’ rights to copy, modify, and redistribute free programs. Users would be neither required to accept the patent license nor restricted from adding new capabilities to the software. They would have the same rights as they would if the developers had never accepted the patent license: those granted by the software’s FOSS license.

If this patent license interfered with the freedoms guaranteed to users by FOSS licenses, it would be incompatible with the OSD and FSD. Because the patent license does not restrict those freedoms, but rather affords some new, limited protections to users and developers within the field of use, it improves on the current situation. Without this license, the patent holders would be in a position to threaten those users and developers as well as others.

The acceptance requirement: an unacceptable burden?

A related objection to the acceptance requirement is that it is a burden for projects with no collective legal identity, because each developer must accept the license personally to be covered (as must each downstream licensee). This inconvenience is largely mitigated by §4 of the draft license, which provides a full release from past infringement upon acceptance. This means that a developer of a VP8 implementation can accept the license at any time—including after being threatened or even sued by a VP8 licensor—and acquire a retroactive release. This feature makes the license functionally identical to a covenant not to sue.

There is some valid concern that the VP8 licensors could subsequently change or withdraw the offer of retroactive release. The license could be improved by a promise not to do so. But the law doesn’t reward manipulation; if the retroactive release appears in the final, published license, the VP8 licensors may well be estopped from subsequently seeking to enjoin developers or distributors who have relied on it in good faith.


SFLC, like the Free Software Foundation, believes that software standing alone should not be patentable subject matter. We join skeptics of the VP8 license and the broader FOSS community in rejecting software patents in all forms, and we will continue to oppose them. But until software patents no longer threaten FOSS, we will look for every opportunity to preserve community development from their destructive effects. The VP8 cross-license provides such an opportunity, in an area of particularly active patenting. It’s not perfect, but no other modern web video format provides nearly the same degree of protection for FOSS implementations.

Update (5/30/2013): the cross license involves patents from several companies other than Google, MPEG-LA, and their affiliates.

  1. SFLC receives no financial support from Google or MPEG-LA.

  2. The code for Google’s VP8 implementation is licensed under a separate 3-clause BSD license approved by the FSF as a free software license and by OSI as an open source license.

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