In an interview with Yahoo!, Mark Ruffalo talked about his career and greatly varying acting experiences this year. He also looked at the future of the Hulk in his own, standalone film, and why that hasn't happened yet.
"I think they've been working on it," Ruffalo said, referencing Marvel Studios and Universal Pictures. The latter studio still owns the production rights to Hulk standalone films, despite Marvel owning the character rights for other films (and distribution rights for a solo movie). It's a cluster of confusion that's enough to turn anyone green and giant.
"Marvel and Universal famously don't get along very well, and so that's working against us, definitely," the actor continued. "But I know for a fact that everyone is holding out hope that one day we can do it. But the nature of the relationship right now, it's a little prohibitive. And I hope that changes; that changes with regimes, it changes over the course of time. But right now, it doesn't look particularly promising," he cautioned.
Another aspect of the ongoing conflict between Marvel Studios and Universal lies in amusement park rights. Marvel had licensed out the Orlando/Florida amusement park rights to Universal, who built a Marvel section of their Universal Studios park there. Disney, now the parent company of Marvel, would love those rights back so they can fully exploit the thousands of characters in the Marvel lineup.
As for where Ruffalo will play the Hulk again, he'll be in Thor: Ragnarok, though he said the script isn't finished just yet. "They'll start shooting this summer, in June," the actor said. He was sad not to be included in Captain America: Civil War, saying, "it's sucky," but the Hulk (and Thor) was taken out of the comic book version of that conflict, too, for fear of him overpowering anyone on the opposite side.