Marvel owned the rights to Red Sonja back in the 70s. Indeed, they changed the character into her well-known form. Placed in Howard's Hyperborean Age, centuries separated her from Marvel's superheroes. She did meet Spider-man, after a fashion, when she somehow possessed the body of his girlfriend, MJ. In 2007, Dynamite Entertainment, which currently owns the comic rights to Robert Howard's warrior woman, teamed with Marvel for a time-twisting story that brought together the wise-cracking web-slinger and the metal-wearing sword slinger.