When to evaluate dual licenses (was: license categories, was: I'm not supposed to use the ECL v2?)

Chris Travers chris.travers at gmail.com
Mon Dec 3 18:13:50 UTC 2007


On Dec 3, 2007 9:20 AM, Wilson, Andrew <andrew.wilson at intel.com> wrote:

>
>
>
> Let me try a more precise formulation: it is axiomatic that the
> license of a derivative work of GPL code must be a license which
> is permitted by the license of the original GPL work.  Better?
> Just trying to prevent this thread from being sidetracked by those
> who question the validity of GPL-imposed licensing constraints on
> derivatives.
> For anyone of that mindset, this entire thread is presumably moot.


Ok, note however that the GPL does not *require* me to extend any
restrictions of the GPL to my own contributions.  For example, I can take
GNU Readline and make some modifications, releasing those modifications as a
BSD-licensed patch.  This would be pointless, however, since whoever used
the patch would have to ensure that the resulting work was not derivative
itself of GNU Readline.

However, suppose I have a work under a permissive license which links to GNU
Readline.  That is permitted too.  But anyone who wants to use GNU Readline
in their proprietary spinoff's cannot.  For example, PostgreSQL links to
both GNU Readline and OpenSSL, and nobody has really complained.

The question in the GPL v2 or later is why one would be forced to extend
restrictions to a fork that the author of the original software did not
choose to extend?  If I contribute to a fork that starts out GPL v2 or
later, and I add content which is GPL v3 or later, the whole project (as a
whole) is now GPL v3 or later, but my contributions could be ripped out and
the work reverted to GPL v2 or later, if someone chose to put in the effort.


>
>
> { ... discussion follows about permitted licenses of GPLv2-or-later
> derivatives ...}
>
> > My theory is that you accept the licensed code under GPL v3 and
> > release your modifications as GPL v3 or later.  That makes the license
> > on the combined work be the intersection of the original (GPL v2 or
> > later) and your code (GPL v3 or later) which is GPL v3 or later.
>
> Hold on a minute, partner.  If you have accepted the V2-or-later
> licensed code
> under V3 and combined it with V3-or-later additional code, the
> intersection
> of these licenses is V3-only.  I do not see how you can both
> "accept the licensed code under GPL v3" and then immediately revert
> to the original V2-or-later inbound license.


Correct.  I think the GP misspoke ;-)

Best Wishes,
Chris Travers
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.opensource.org/pipermail/license-discuss_lists.opensource.org/attachments/20071203/7ada0890/attachment.html>


More information about the License-discuss mailing list