Dual licensing with two copyleft licenses

[Chad.Woodford at windriver.com]

> Seriously, though it's important to remember that Contributor doesn't
> have free rein in deciding how his/her modifications are licensed.
> Copyright law gives the Originator considerable say in how derivative
> works are published. Unless Contributor1's contributions are
> sufficiently independent to be a standalone copyrightable work, s/he is
> subject to Originator's whims about licensing.
> 
> This is, after all, why and how copyleft works.

Yes, but in this admittedly contrived example, where O has made the work
available under A and B (which is the same as saying A or B here), then a
downstream licensee can choose to accept either license A or license B or
BOTH.  To be more explicit, pretend license A says that you can make a
derivative work but it must be licensed under license A.  License B says the
same thing.  For a contributor to choose both licenses for his derivative
work is completely acceptable.  At least in my mind.  Are you saying that
once a contributor has made a modification pursuant to one license then it
is frozen that way?  How are we to know whether the contributor had the
intent to modify under license A or B in this example?  What if his intent
was to modify under both simultaneously?

> > Because the downstream contributor is never changing or
> > adding to either license, it does not matter that one of the licenses
> > forbids dual licensing, etc., or even that some licenses treat the
> > contributor as a sublicensee of the previous contributor and some treat
> the
> > contributor as a licensee of all the previous (c) owners.
> >
> > Does that make sense?
> 
> I'm afraid not. If neither license allows dual-licensing derivative
> works, I have a hard time seeing how the alternation between them does.

I could be totally off the mark here but I'm starting to think you're
confusing the license to a copyrighted work with the work itself.  Despite
the usual appearance of license attributes sort of running with the code,
keep in mind that the original licensor (the initial developer) can license
the code in many different ways (à la MySQL).

Cheers,
Chad