On Sun, Jan 27, 2013 at 2:17 PM, Theodore Ts'o <tytso@mit.edu> wrote:
> Consider for the sake of argument, what might happen if some very
> important piece of code starts using the copyleft-next license, and > then whatever organization which is handed the responsibility of > maintaining the copyleft-next license releases a new version which
> basically says, "new rules! copyleft-next-v2 == new BSD-style license"
In the context of a program licensed under "GPLv3 or later", I remember someone asking RMS that question during one of his public talks. Unfortunately, I can no longer find a reference to his exact answer but my recollection of it is that Section 14 covers that:
"Such new versions will
be similar in spirit to the present version"
A non-copyleft GPLv4 would not be similar in spirit and so the "upgrade clause" would no longer apply.
It does feel like a fairly weak protection though.