I’d say the only one notable that was owned by another studio was Fisk. Everyone else who was created as a Spider-Man mobster, Tombstone, Hammerhead, Silvermane, Crime Master, Lobo Bros. Etc. were up for grabs. I suppose they don’t offer too much of a spectacle after starting from fighting alongside the Avengers. Fisk being out of bounds is actually the specific reason why they used Tombstone as the “Big Man” in the Spectacular animated series. I think the idea with mobsters and the superpowers arms race is that when super heroes start targeting smaller threats that aren’t going to blow up the universe, career criminals will have to step up their game to be successful.