Subject: Re: Apache 2.0 and GPL compatibility
From: Eugene Wee <eugenew@starhub.net.sg>
Date: Fri, 07 Jan 2005 15:19:16 +0800

Hi Bob,

Just in case you didnt notice, AFL 2.0 and 2.1 grant the right to 
sublicense as well, for both copyright license and patent license.

 > why would granting
 > or revoking a patent license for the original work have any effect on
 > implicit patent rights for the derivative work
This is something of a stab in the dark as I'm a legal layman....
As I understand it, software patent rights apply to the creation and use 
of software that implements the given invention, so whether or not the 
work is independently created or a derivative of the software, if patent 
rights are revoked, then one cannot legally use the derivative or create 
such independent software, or even use the software itself.

Also, one cannot sublicense more rights than one is granted, so if one 
does not have the patent rights (anymore), then one cannot sublicense them.

Hope this helps,
Eugene Wee

Bob Scheifler wrote:
> In a March 2003 discussion on this list about whether the AFL was or
> wasn't GPL compatible, it seemed that a key point was that, because
> the AFL does not grant the right to sublicense, the AFL applies to
> any parts of an original work that remain in a derivative work, even
> if the derivative work as a whole is under a different license.
> 
> The Apache License version 2.0 does grant the right to sublicense,
> as I understand it. Was that factored into the analysis given here:
>     http://www.apache.org/licenses/GPL-compatibility.html
> ? If the right to sublicense means no part of the derivative work
> needs to remain under the original license, then why would granting
> or revoking a patent license for the original work have any effect on
> implicit patent rights for the derivative work?
> 
> - Bob [risking the wrath of the gods]
>