Troll Lord Games

Let's say a writer wanted to submit material to your company. Either an adventure, or a complete campaign setting but they wanted to own the rights to the world. Would this be an acceptable request?

let's say Ed Greenwood told TSR, you can use Forgotten realms, but I own rights to Faerun and all it contains.

Is this an acceptable business offer?

If I were the one being asked, I would say: no, but I will grant you a license, which you pay for, to use my material - that way there is no confusion about who owns what. For example, if you wanted to create a world and use the C&C rules for it, rather than have TLG do the publishing/editing/layout/blah blah, you are responsible for it (it is your work, after all, and you want to keep rights to everything), so you ask Steve for permission to use the non-Open content that defines the C&C game to make your world possible. Only you can make new material for the world, but it is using C&C as its source.

That is more equitable for all parties, in my opinion.

But... I don't make these decisions.