Re: a minimal copyleft
Andrew Suffield <firstname.lastname@example.org>:
> > The GPL doesn't say "the original author's preferred form for modifications",
> > and that's not an error.
> It doesn't need to; this is implicit in the nature of copyright
> law. The license comes from the copyright holder, so it's their
> preference which counts.
The example I gave was that I write a document in plain text and
someone else "typesets" with Word (if you want you can have them edit
the text too). Then the Word document has two authors and two
copyright holders, who may have different preferences.
But my example wasn't that good. If I were to convert the Word
document to plain text, edit it, typeset it with LaTeX and distribute
the PostScript, the GPL would probably only require me to supply the
LaTeX as source, as that would be the preferred form for modifying my
version of the document, even if the other author would have preferred
me to modify the Word document.
A better example might be where I create a bilingual dictionary in
plain text using a data file and a Perl script then give the plain
text to someone who typesets it using Word and manually corrects a few
glitches. Now, the source of the final PDF or hard copy could be the
data file and the Perl script, for me, or the Word document, for the
other person, as I can't use his Word, and he can't use my Perl. This
is not an unrealistic example; it is exactly what happened with some
of the material in question.
I've come up with another slightly less minimal licence which arguably
includes an implicit requirement to either supply source or tell
people how to obtain source. It goes like this:
# Public Licence: You may do anything you want with this work provided
# that no additional legal or technical restrictions are placed on
# derived works, you give reasonable help to anyone who wants to modify
# your derived work, and you inform recipients of this licence.
I have to decide by the end of this week how to licence the course
material I referred to. At present it looks like I'm going to suggest
dual-licensing it with GPLv2 and a one-sentence licence like the one
above while asserting copyright on behalf of a registered charity and
inviting people to assign copyright to that organisation. That
combination ought to cover any eventuality.
I'm still keen to receive suggestions about how to improve either of
my one-sentence licences. Thanks for the suggestions already received.