How would that work?
> You'd need a custom license where everyone in the world could use the results except for the contributor
That one is incompatible with copyright laws in many countries outside USA.
How so? You can't sign away your interest in a copywrighted work?
For many open source projects, there is a CLA (contributor license agreement) that must be signed before contributions can be accepted. The Free Software Foundation (which holds the copyright for most/all? GNU tools) is pretty in/famous for requiring it. Their reasoning: If there are copyright violations, they have the time and financial resources to pursue the violators.
Are you saying that these CLAs and their intended purpose are invalid in some jurisdictions? If yes, please share some examples. To be clear: I'm only interested in "normal/regular" jurisdictions that have at least accepted the Berne Convention.
> You'd need a custom license where everyone in the world could use the results except for the contributor
> That one is incompatible with copyright laws in many countries outside USA.
Does authorship confer usage rights?