On Tue, Nov 09, 2010 at 12:10:13PM -0800, dmg wrote:

Don't confuse a conjunction of terms with a disjunction. GPLv2 and
"ANY later version" is a conjunction of
licensing terms, while 'MPL1.1 or LGPL 2.1' is a disjunction.

<delurking>

Actually, it is not inherently clear whether "GPLv2 or any later
version" licensing is meant to be conjunctive or disjunctive, but it
is my sense that the majority view in the open source developer
community is that it is disjunctive. By that I mean, if I get some
"GPLv2 or later" code, I can redistribute it under "GPLv2 or later"
(which is what is done 99% of the time), or (by revising the license
notices) "GPLv2 only", or (by revising the license notices) "GPLv3
only" [or "GPLv3 or later"]).

As a historical example, in ~2006 active developers of BusyBox acted
on the assumption that "GPLv2 or later" was disjunctive, and made some
effort to alter license notices to say "GPLv2 only". Bruce Perens, one
of the early developers of BusyBox, objected to this, arguing that
GPLv2, in requiring preservation of license notices, prevents the
removal of the "or later" choice. See:
http://lwn.net/Articles/367058/

The FSF's position is that "GPLv2 or later" is disjunctive, precisely
like a "MPL 1.1 or LGPL 2.1" dual license, and there was some effort
in GPLv3 to clarify that.

- RF