[Wolves] GPL Terms

Aquarius wolves at mailman.lug.org.uk
Thu Oct 24 11:47:03 2002

Simon Gill spoo'd forth:
> Aq, since you are our resident GPL guru, what do you think about adding
> these exceptions to the GPL:
> 1) Unless you have made significant modifications to the software you
> may not redistribute it.
> 2) All modifications must be submitted to us in some form.

Nope. Can't do either of those. The GPL is very very strict about
adding new requirements; you can't do it.
is useful here; browse through it and see *why* the licences declared
as GPL-incompatible are so. For example, the Open Public Licence is GPL
incompatible because "it requires sending every published modified
version to a specific initial developer", which is your requirement 2.
Daniel Bernstein's licences "are not free software licenses because
they do not permit publication of modified versions", which is your
requirement 1 to some extent; defining "significant" is an impossible
task, and restricting redistribution is a violation of the GPL.
> I have just about got my boss interested in Python and the GPL, but he
> needs some proof that people aren't going to rip off our code and spread
> it about under their name. The idea is to make it possible for people to
> keep their rights under the GPL and, ahem, _ask_ them to help other
> people in the community without us haemorrhaging money.

Python code is often distributed under the Python licence, but that's
not what you're looking for. You're not going to like this next bit.
RMS would say that what you want to do is convince Free Software coders
to give you *their* code and their rights to their code without reward,
but you're not prepared to donate *your* code back to the community.
He's right, pretty much. Now, I appreciate that this is not at your
instigation; your boss is promulgating this. The fact that he is,
however, means that he doesn't understand the open source community;
instead, he's trying to do what Sun do, which is get everyone to give
them free code that they can then sell and other people can't.

As I say, look through the GPL-compatible licences page; the FSF, while
being zealots and having the hardest-core interpretation of the GPL's
provisions, have useful notes on licences out there, and maybe your
boss would be more amenable to one of those. The other reason for doing
this is that you should not invent your own licence. There are too many
licences already, and (as this question makes clear) interpretation of
them is non-trivial -- even lawyers can't agree, so randomly adding
provisions to a licence is a bad idea. If your licence is found to be
mutually inconsistent with itself (which it would be if it was a
GPL-plus-your-clauses-above) then it might be ruled to have no validity
at all in a test case -- at best the code would be deemed to not be
copylefted at all and any third-party contributions to your codebase
might have to be removed, which would be a setback.

Hope that helps.


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