Why an 'X-Men: Days of Future Past' teaser is in 'The Amazing Spider-Man 2' credits

The Amazing Spider-Man 2 has already theaters in some countries, though we hear in the U.S. must wait until May 2 to feast our eyes upon the movie. Fans who have already seen it received a special treat when a scene from Bryan Singer's X-Men: Days of Future Past appeared after the credits.

Fox owns the rights to the X-Men movies, while Sony has Spider-Man. Fans naturally turned giddy and thought this hinted at a possible crossover between the two franchises even though Spider-Man was not in the scene, nor did it have anything to do with the webhead's movie. Now, Variety reports the reason for the surprising scene appearance:

"The reason, Variety has learned, is that Spider-Man director Marc Webb had an existing contract with Fox Searchlight to helm another film following 2009′s 500 (Days) of Summer. After The Amazing Spider-Man in 2012, Webb's negotiations briefly stalled with Sony as he was caught in a tug-of-war with Fox. Eventually, Fox agreed to allow Webb to direct Sony's Spider-Man sequel, but only if Sony would promote its X-Men film for free."

So not only does this not indicate a crossover, but it also shows that Fox held the cards in this situation. It also seems to indicate how much Sony wanted Webb for the sequel because it agreed to the terms.

For those wondering, the scene in question featured Mystique, Toad and Havoc fighting Stryker and his troops. We'll have to wait until May 2 to see if the scene appears in the U.S. release.

What do you make of this situation? Do you see a crossover ever realistically happening? Let us know in the comments below.