Subject: RE: combining software under different licenses
From: "Lawrence Rosen" <lrosen@rosenlaw.com>
Date: Sat, 29 Aug 2009 07:19:01 -0700

 Sat, 29 Aug 2009 07:19:01 -0700
Mark, I'm sorry if I was unclear about the compatibility of GPL and the Apache license.

The problem is the following: Apache policy is to release all software it distributes
under the Apache License. If Apache were to include links to GPL software and as a convenience
to its customers also distribute the GPL software itself, then FSF would expect the
entire package to be under the GPL. There is no way that ASF can honor its own licensing
philosophy and also respect FSF's attitude about linking creating a derivative work.

This says nothing about combinations that third parties can make by themselves, which
can be done by any user who wants to. It also says nothing about the ability of a GPL
distributor (GPLv3 only, according to FSF) to include Apache code in that software and
link to it, as long as the resulting combination is under GPL.

Please let me know if you think I'm analyzing this license compatibility problem incorrectly.
I'd personally like nothing better than to encourage ASF to be free to combine GPL and
Apache software (through linking, of course) without "infecting" the Apache code. 

/Larry





-----Original Message-----
From: Mark Wielaard [mailto:mark@klomp.org] 
Sent: Saturday, August 29, 2009 2:00 AM
To: license-discuss@opensource.org
Subject: Re: combining software under different licenses

Hi Larry,

On Fri, 2009-08-28 at 16:54 -0700, Lawrence Rosen wrote:
> John Cowan suggested:
> > Just out of an abundance of wanting to get it right, you should point
> > out that the controversy between FSF and ASF is only about the GPLv2,
> > and both groups agree that Apache-licensed software can be included in
> > works derivative of GPLv3 works.
> 
> But not vice versa, unfortunately, for both GPLv2 and GPLv3, because of
> FSF's desire not to allow linking of GPL software to Apache works without
> deeming the Apache software a derivative work.

I am not sure I am following your reasoning, or I am missing something
subtle. I would assume it is normal that a larger work derived from both
GPL and ASL licensed software (or any combination of compatible OSI
licensed software of course) should come with the grants and obligations
of the combined result. Whether you call the larger work a collection of
interwoven stitched hacks or derived from carefully designed
interactions, both sets of rights come into play when distributing the
whole.

The confusion about the GPLv2 vs ASLv2 was that it wasn't clear you
could obey both sets of requirements at the same time, GPLv3 cleared
that up.

I found the following guide by the FSLC a good way to show how to mix
and match free software under different licenses and make it clear what
rights and obligations users have for the various parts that make up the
whole derived work:
http://www.softwarefreedom.org/resources/2007/gpl-non-gpl-collaboration.html
That makes it easy to do the diligent recordā€keeping you propose in your
paper.

Cheers,

Mark