zlib specification license
Has this license been evaluated before? RFC 1950-1952 contains:
Copyright (c) 1996 L. Peter Deutsch and Jean-Loup Gailly
Permission is granted to copy and distribute this document for any
purpose and without charge, including translations into other
languages and incorporation into compilations, provided that the
copyright notice and this notice are preserved, and that any
substantive changes or deletions from the original are clearly
A pointer to the latest version of this and related documentation in
HTML format can be found at the URL
The license initially doesn't give permissions to make modifications,
although it later require that any changes are clearly marked, which I
guess can be seen as the intention is to allow modifications.
Is the license DFSG-free?