For what it's worth, I had read somewhat recently somewhere that it depends on what Franchise and their history of dealing with such things. From what I'd read Star Trek owners were generally okay with people making things for it. Star Wars, not so much. I think something like Marvel (especially now that Disney owns them) would also probably raise a stink on any of their properties.
Maybe make something in the Firefly Universe? We could always use a game like that.
