Proper license note for Maxima and Maxima-derived works

On 2012-12-06, Stefano Ferri <ferriste at gmail.com> wrote:

> since I have modified the file merror.lisp and I need to redistribute a
> small part of it it along with my program, which is released under the
> terms of the GNU GPL v3 or later, I would like to know which is the correct
> way to redistribute it. It is a very little modification, but doing things
> in the right way is necessary.

I agree that you should try to do the right thing, but my advice is,
don't lose sleep over it.

(1) Bill Schelter (requiescat in pace) got permission from US Dept of
Energy, the nominal owners of DOE-Macsyma, to release his version under
terms of the GNU GPL. Nobody now involved in the project has any
authority to revise those terms for the stuff that was in DOE-Macsyma at
that time, which, I believe, includes merror.lisp. No particular version
of the GPL was mentioned in the DOE authorization letter. The GPL itself
states that no particular version is the same as version 2.

(2) Nobody knows exactly what the GPL allows and doesn't allow. Not even
the FSF (Stallman's organization) -- they make various claims but only
court rulings on copyright law (specifically, what counts as a
derivative work) can really clarify things.

(3) A license violation is a matter for civil, not criminal, law. So
only an injured party could bring a lawsuit against you. Questions for
you to consider: Who would be injured by your failure to license
merror.lisp properly? If you make an effort in good faith to adhere to
the GPL, would they really care?

Disclaimer: I am not a lawyer.

Hope this helps,

Robert Dodier