Re: Sweet Tooth : license of uploaded extensions for GNOME Shell ?

[Owen Taylor <otaylor redhat com>]

On Thu, 2011-09-15 at 14:47 +0200, Maciej Marcin Piechotka wrote:
> On Thu, 2011-09-15 at 10:33 +0200, thibaut bethune wrote:
> > Hi,
> > 
> > I've just learned about that project and i find it great.
> > 
> > I haven't tried it yet but i saw that video
> > http://www.youtube.com/watch?v=luZuhn5_b_8
> > 
> > I just wanted to be sure that the interface will precise the extension license.
> > 
> > Ideally it should maybe require the uploaded extension to have the
> > same license that GNOME itself ?
> > 
> > Thanks
> > 
> > Thibaut
> > France
> 
> I may be wrong but as gnome-shell is on GPL isn't only GPL legal (but
> IANAL)?

It's a somewhat complicated question:

If the extension isn't a derived work of the GNOME Shell code, then it's
fine to distribute the extension code under whatever license you want -
BSD, proprietary, whatever. Because it's not a derived work of GNOME
Shell, the license of GNOME Shell can't matter.

Now, the combination of GNOME Shell and the extension wouldn't be
distributable. So as a _policy_ thing (not a legal thing), we we
probably in any case want to require all extensions on
extensions.gnome.org to be at least GPL compatible - to be under GPL,
LGPL, BSD, MIT, etc.

But are extensions derived works of the GNOME Shell code? If you copy
code from GNOME Shell, obviously that makes your code a derived work.
If you don't copy any code - if all the code is written from scratch,
then there is still an argument that since you  had to look at the GNOME
Shell code to write your extension, you had to test your code with the
shell, etc, it might still be a derived work. (This is something that
has been discussed at great length with respect to the kernel modules;
I don't think there's a definitive answer.)

To me, the simplest thing is that we require authors to agree to
distribute their code under the GPL v2 or later when they upload an
extension to extensions.gnome.org, and that's the license we use
when distributing extensions.

If an extension author wants declare in a README file or code comments
that their extension code is also available under more permissive terms,
that's their call, and it's not up to us to check that assertion or
prevent them from making it.

- Owen