Earlier today, we reported that fans who stay to the end of Sony's The Amazing Spider-Man 2 credits will be treated to a scene from 20th Century Fox's X-Men: Days of Future Past. While the scene does not tie the two franchises together, many have wondered why the rival studios would team up for this kind of cross-promotion, with speculation that they may be teaming up for some sort of superhero crossover in the future. Variety has a new report which reveals that a Spider-Man and X-Men hybrid movie is not in the works, and that there is a simple, contractual reason why this extra scene was added to prints of The Amazing Spider-Man 2.

When The Amazing Spider-Man director Marc Webb was in negotiations to make The Amazing Spider-Man 2, the talks hit a brief snag, since the filmmaker is still under contract to make one more movie with Fox Searchlight, following his 2009 directorial debut (500) Days of Summer. 20th Century Fox eventually allowed Marc Webb to make the sequel, but only if Sony would promote X-Men: Days of Future Past for free.

Marvel Studios helped make these end-credits scenes popular starting with 2008's Iron Man, but those scenes helped promote their own movies, and it's extremely rare to see one studio help promote another's blockbuster in any way. Of course, Marvel Studios does not control the rights to X-Men and Spider-Man, although both Sony and 20th Century Fox are using their now-famous end credits scenes in quite an unusual fashion.

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Marvel Studios' Kevin Feige revealed in November that it still may be possible for Marvel Studios, 20th Century Fox and Sony to bring all of these franchises together, but it likely won't happen for many years to come, especially since Marvel Studios controls the rights to plenty of Marvel comic book characters. Fox's Wolverine and Sony's Spider-Man have previously been a part of the Avengers in the Marvel comics, but only time will tell if these characters will finally get together under one cinematic roof.

Would you like to see these three studios work together to make this happen? Chime in with your thoughts below.