Subject: RE: Compatibility of the AFL with the GPL
From: "Lawrence E. Rosen" <>
Date: Tue, 11 Mar 2003 23:11:06 -0800

> > ***Anyone*** is free to take software licensed under the AFL and 
> > re-license it under any license, including licenses not 
> containing the
> I just want to confirm that I have interpreted the above 
> statement correctly.
> Anyone can take APL licensed software as a whole and 
> distribute it under different licensing conditions, but the 
> license of the individual source code files cannot be changed 
> from APL into another license. That is, I cannot take APL 
> licensed software and physically replace the license with the GPL.
> Is this correct? (if not, I would be seriously concerned 
> about suggesting anybody to apply the APL to any software.)

If I read your words correctly, yes, that's the intention.  Let me
describe it more precisely this way:

Person A licenses copyrightable work W to Person B under the AFL.
Person B must honor the terms and conditions of the AFL.  The AFL
permits Person B to create collective work W+X, to create derivative
work W', and to distribute copies of W, W+X and W' under any open source
or proprietary license not expressly incompatible with the AFL,
including the GPL and Apache licenses.   

Because the AFL does not allow sublicensing, W (alone or as part of W+X
and W') is always subject to the AFL and the license to W always comes
from Person A.  [Anyone can look at the source code to see that trail of
ownership, because of the Attribution Notice provision in the AFL.]
Person A can always enforce his license to W against anyone who uses W.
And anyone who has a copy of W+X or W' has two licenses, one from Person
A (for that part that was W) and one from Person B (for W+X or W').
Person A is not responsible in any respect for W+X or W'.

In practice, because the AFL is so forgiving a license, Person A won't
much care what Person B does with W.  And the ultimate consumer will
know that at least W is free and open source software regardless of what
Person B does.   

/Larry Rosen

license-discuss archive is at