The GPL is distributed under much more restrictive terms than itself:
> Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
@alexbuzzbee Because, otherwise, someone could remove the prohibition on adding additional restrictions, call that GPL, and put their offering under it.
(For GPLv2, clauses 6 and 7 become unsatisfiable if you add additional requirements on top of it. For GPLv3, Section 7 explicitly grants you permission to ignore any additional restrictions applied on top of it outside a whitelist of things like prohibiting misrepresentation or declining to grant trademark use rights.)
@ssokolow I'm fully aware of why, I just find it mildly amusing.
@alexbuzzbee Yeah. It's sort of a https://en.wikipedia.org/wiki/Paradox_of_tolerance situation.
...I think they also did the same trick as Creative Commons and trademarked "GNU GPL" so they can withhold permission to use it to describe anything other than their version.
@ssokolow Very sensible precaution. I would definitely believe that they did that.