When asked if Hulk would receive the solo treatment in Marvel's master plan, Ruffalo responded, "As far as a Hulk movie, a standalone Hulk movie, Marvel doesn't really have the rights to that yet. That's still Universal's property, so there's that issue. That's a big impediment to moving forward with that. Now I don't think that's insurmountable, by the way, but I don't know where it's going from here for me."
Regardless, the actor isn't opposed to sticking around for more Marvel ensemble films even after his contract is up. "I think it's four now, but that could always go further. That could include different -- I could show up in another character's movie; I could do 'Avengers' 3 and 4; I could do a Hulk standalone; I could do a combination of those things. That's four or five, I think."
Ruffalo stars as the Hulk in "Avengers: Age of Ultron," which opens May 1.