[FFmpeg-devel] [PATCH] VP8 de/encode via libvpx

[Uoti Urpala]

On Thu, 2010-05-20 at 09:43 -0400, Ronald S. Bultje wrote:
> On Thu, May 20, 2010 at 3:54 AM, Diego Biurrun <diego at biurrun.de> wrote:
> > On Wed, May 19, 2010 at 08:52:43PM -0400, Ronald S. Bultje wrote:
> >> On May 19, 2010, at 7:38 PM, Uoti Urpala <uoti.urpala at pp1.inet.fi>
> >> wrote:
> >>> If you're talking about the patent clause, then I think it's not
> >>> compatible with GPL 2 but probably is compatible with GPL 3.
> >>
> >> Doesn't v3 require a grace period?...
> >
> > Come on, please just read the license instead of making wild claims..

> "Moreover, your license from a particular copyright holder is
> reinstated permanently if the copyright holder notifies you of the
> violation by some reasonable means, this is the first time you have
> received notice of violation of this License (for any work) from that
> copyright holder, and you cure the violation prior to 30 days after
> your receipt of the notice."
> 
> Notice the last sentence, "30 days". Any shorter is a limitation that
> is GPLv3-incompatible and thus voids the license. (BTW I'm discussing
> the patent license with SFLC so you may draw your own conclusions from
> whatever I say until I forward an official response from SFLC.)

Actually I doubt now whether it's incompatible with GPL 2 either. The
termination part only says that the patent licenses you got from Google
under the VP8 license will terminate if you start certain kinds of
patent litigation; it doesn't require you to make any explicit patent
license yourself (which would be compatible with GPL 3 but not GPL 2) or
forbid you from starting such ligation. As such it can be viewed as
granting additional permissions only, and isn't any worse than just not
having such a section would be, except maybe if you interpreted a
license without such a section to give an implicit patent license
without such conditions. And even if such a license explicitly said that
no patent license is granted by that license itself, I think that should
not be a problem when used with GPL, because it would not _remove_ any
licensing required by GPL.

Also compare the Apache license version 2.0 which has patent
requirements that look stricter and which is listed as explicitly
compatible with GPL 3 on gnu.org.