Subject: Re: termless copyright and patents
From: <stephen@xemacs.org>
Date: Sat, 7 Oct 2006 23:39:03 +0900

Ben Tilly writes:

 > But if you redistribute it, then under item 6 you "may not impose
 > any further restrictions".  Again it does not say whether you'd be
 > imposing those restrictions through contract law or patent law, so
 > you're not allowed to use either to impose those restrictions.

Your broad interpretation of "extra restriction" would mean that once
you have released GPL code into the wild, you are no longer allowed to
use a *copyright* license that is incompatible with the GPL, because
that would be a restriction on people's ability to combine your non-
GPL-compatible code with your GPLed code.

I say that you are restricted by copyright law from trying to use
copyright to restrict running the program, by the GPL and the doctrine
of reliance (which theoretically prevents you from withdrawing your
license once you've published it) from restricting use of the text of
the program, and by the GPL's implicit patent license (and in the case
of GPLv3d2, section 11) from restricting practice of the claims
embodied in code you convey, or license for release in GPLed code.[1]

Take a deep breath and think about it before you respond.


Footnotes: 
[1]  All of the statements require a clear chain of title