GPL-3-with-idsoft-extra-terms

Summary:
Id software added several terms to the software license, ammending the GPL-3.

This is NOT in a contradiction to the GPL-3 §10, as GPL-3 §7 explictly allows
to override the paragraphs idsoft does.

This was also discussed on debian-legal with the same conclusion:
The extra terms are comptabile with the GPL. (Doom3BFG has the same license)
See https://lists.debian.org/debian-legal/2014/10/msg00003.html

Analysis after initial reject:

GPL V3 in §10:
You may not impose any further restrictions on the exercise of the> > rights
granted or affirmed under this License.

However, §7, "Addtional Terms" has an exception to this: (I'll quote
only the important sections here):

  7. Additional Terms.
  (...)
  Notwithstanding any other provision of this License, for material you
  add to a covered work, you may (if authorized by the copyright
  holders of that material) supplement the terms of this License with
  terms:

    a) Disclaiming warranty or limiting liability differently from the
    terms of sections 15 and 16 of this License; or
    b) Requiring preservation of specified reasonable legal notices or
    author attributions in that material or in the Appropriate Legal
    Notices displayed by works containing it; or
    c) Prohibiting misrepresentation of the origin of that material,
    or requiring that modified versions of such material be marked in
    reasonable ways as different from the original version; or
    d) Limiting the use for publicity purposes of names of licensors or
    authors of the material; or
    e) Declining to grant rights under trademark law for use of some
    trade names, trademarks, or service marks; or
    f) Requiring indemnification of licensors and authors of that
    material by anyone who conveys the material (or modified versions
    of it) with contractual assumptions of liability to the recipient,
    for any liability that these contractual assumptions directly
    impose on those licensors and authors.

  All other non-permissive additional terms are considered “further
  restrictions” within the meaning of section 10.

The last quoted sentence makes it clear that other changes except the
ones from the list in §7 are "further restrictions" and implicitly says
"those in the list are not". For now a) is the important one.

idsoft utilizes this exceptions and overrides §15 and §16 with their
own versions, but IMHO above shows that they are free to do that.

There is also nothing in that point a) that disallow to say "I
completely manage §15 and §16 myself, thus the original ones are void",
so saying "Replacement of Section 15.  Section 15 of the GPL shall be
deleted in its entirety and replaced with the following:" and
accordingly "2. Replacement of Section 16.  Section 16 of the GPL shall
be deleted in its entirety and replaced with the following:"
is OK too.

Looking at idsofts §15, this is a just a rephrased version of the GPL
15, with nothing special in it. [1]

§16 idsoft is also not really fancy rewrite of GPL §16. [2]

There is also a third point in idsofts' additional terms: [3]
3. LEGAL NOTICES; NO TRADEMARK LICENSE; ORIGIN.
but that is also covered but the exceptions in the GPL,
bullet poinst b), c), d) and e)

And finally, point 4 in idsofts addendum, INDEMNIFICATION
is covered by bullet point f). [4]

Bottom line, I'm sure that this license is perfectly fine and distributeable.

-- 
tobi
