Release comercial application's sources as GPL but with restr iction in usage

[John Cowan]

Chris Yoo scripsit:
> I think that accepting contibutions from others is a fundamental aspect of
> the dual licensing model - improvements are continuously made by the
> community (free, from the original copyright holder's perspective) and are
> incorporated into the non-open source version for sale. Provided that
> contributions also remain available under the open source licence, it's a
> win-win situation for both the contributor and the original copyright
> holder.

Then you have to make sure that the contributor permits this.  In practice,
the contributor will find it very hard to sue, but that doesn't mean that
trampling on other people's moral rights is a good thing.

> I am curious as to the nature of the 'joint' copyright assignment, as used
> by openoffice (http://www.openoffice.org/contributing/programming.html)? How
> does this differ from an outright copyright assignment? Does it allow both
> the contributor and the recipient to do as they wish with the contributions,
> without the permission of the other party? 

Just so.  Joint copyright holders have equal rights to license their works
as they will, provided that each is responsible to the other(s) for proportionate
shares of any profit.

-- 
John Cowan
        jcowan at reutershealth.com
                I am a member of a civilization. --David Brin