But is it certain that Bethesda doesn't legally have the intellectual rights of any mod for their games?
Well … I doubt about the concept of the whole world. What would they do with it anyway ?
But yes, I know that early in the beginning the lawyers - so I was told - had made up a kind of EULA ffor NWN which automatically transferred everything into being property of Bioware that was made with the editor.
The story goes that "after an outcry of the community" this was changed.
But in principle, ANY editor could be seen as a cost-free wayfor companies to get IP for free, whithout having to pay anything for that, and to exploit it at will.
Which means I'm careful with that.