On Tue, Dec 8, 2009 at 6:10 PM, Erik de Castro Lopo <mle...@mega-nerd.com> wrote: > Tom Tobin wrote: > >> The background situation: X is a library distributed under the GPL. Y >> is another library that uses that library and requires it in order to >> compile and function. > > You probably also need to bring in application Z which uses library > X via library Y, because library Y is not usable by itself.
I think this is implicit in calling something a library; are there any questions where it would come up? >> 1) Is there any scenario where Y can be distributed under a non-GPL >> license (e.g., the BSD)? > > You need to make sure they know that your are talking about the 3 clause > BSD license, the one the FSF calls the Modified BSD license. Good point. >> 3) If Y must be released under the GPL under the above scenario, and >> someone subsequently wrote library Z, an API compatible replacement >> for X, and released it under the BSD license, would Y's author now be >> permitted to release Y under the BSD? > > The author is always allowed to relicense their own work under whatever > license they choose. Well I think that's actually what we're wondering here — under what circumstances is Y's author permitted to choose his license at will? > For instance there are libraries released under > the GPL which are also available under a commercial use license for > use in closed source products. The requirement here is that the library > is soley written by the person doing the dual licensing and/or all other > contributors have assigned their rights. But those libraries don't, in turn, depend on GPL'd libraries written by different authors. I think the answer to the "can Y's author choose the BSD3 for Y" question will also answer this for cases where there's a further, different-author GPL dependency involved. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe