multilicensing and relicensing doubts

[Anastasios Hatzis]

On Monday 16 April 2007 17:56, lolo wrote:
> Hi,
>
> I have some doubts about licensing which i didn't find them solved reading
> the gnu.org's site and i thought of asking them here because maybe replies
> can be added there later...
> (maybe i haven't find the proper urls and maybe i'm asking dumb/repetitive
> questions...ignore and sorry if so)
>
> Multilicensing:
> 1-Could i license something under 2 diferent copyleft compatible licenses?
>
> 1.1-Could i license something under 2 copyleft uncompatible licenses?
>
> 1.1.1-If so, Could i also add a third one to the same document?
>
> 1.1.2-Could i also license it with a fourth free, non-copyleft, gpl
> compatible one?

I'm not a lawyer, but if I'm mistaken, I'm sure someone will correct me :)

You, as the author, can use as many licenses for your own work as you want. 
Just make sure you have the rights to do so, for example the approval of 
other co-authors. In some countries additional aspects have to be considered 
by employees.

I just don't think that it makes much sense to use multiple licenses for the 
same work (e.g. GPL + BSD + Proprietary-World-Domination-License for the 
source-code). Some companies use dual-license strategy (GPL + 
proprietary/closed-source license) so they can match different users' 
requirements, along some other aspects. I have some problems to imagine the 
benefit of a BSD + proprietary/closed-source license since BSD license would 
not prevent a licensee from using it for the purpose for which you may want 
to use the other license.

>
>
> Re-licensing:
> Project 'a' was GPL when it was 1.1, now is 2.2 and has changed into LGPL,
> ok?
>
> Project 'b' was GFDL and now hasn't got any license displayed, ok?
>
> Project 'c' was GFDL and they changed the license banner into another
> copyleft uncompatible one, ok?

As far as you are talking about your own work, re-licensing is the same as 
with multiple licenses. You can change the license for any release you make. 
But be aware that you can't re-license any work that already has been 
licensed to a licensee. If 1.1 is released under GPL any licensee can modify, 
re-distribute, etc. this 1.1 again under GPL, whatever license you use for 
the 1.2 or 2.2.

The same applies for project 'c'. You take the last version licensed under 
GFDL, modify it and release it yourself under GFDL.

BTW: GFDL is for documentation. :)


Best regards,
Anastasios