Subject: Re: Compatibility of the AFL with the GPL
From: Russell Nelson <>
Date: Fri, 14 Mar 2003 22:20:26 -0500

Greg Pomerantz writes:
 > > Lawrence E. Rosen writes:
 > >  > OK, guys, play with me one more round.  This time, let's do it in the
 > >  > form of a law school exam question and let's get the lawyers and IANALs
 > >  > on this list to chime in:
 > > 
 > > Nahhh.  None of this is necessary.  There's nothing in the AFL that
 > > says that you must use the same license on derivative works.
 > > Therefore, without reference to any other terms of the AFL, it is
 > > trivially compatible with the GPL insofar as derivative works get
 > > licensed under the GPL.
 > Russ, the AFL is not sublicensable. If you're using AFL code (or a
 > derivative of AFL code), you need a license from the author,
 > regardless of who you got that code from.

One of the things you're allowed to do under the AFL is create
derivative works.  There is nothing in the AFL which requires you to
license that work under the AFL (unlike the GPL, which *does* require
GPL'ed derivative works).  So, when you get an AFL-licensed work, you
also receive a license from the copyright holder, licensing you to do
whatever you want, modulo abusing trademarks, or suing Mutual Defense
licensors.  Does that bind anybody who received a copy of your
derivative work?  No, because that work is licensed under the GPL, and
the AFL very specifically says that Mutual Defense only applies if the
license says Mutual Defense.  The GPL doesn't, and so while *you* lose
your license to distribute, the people you have distributed the GPL'ed
work to don't.  Does it now suck to be you?  Yes, and you should have
thought about that *before* you sued.

Many and subtle are the powers of Larry Rosen.

-russ nelson   | "What Problem Are You Trying
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