Originally Posted by Mr. Dent
Because of money. How would they split it? And why would Disney share proceeds with Fox/Sony to have their characters in their movies when they do just fine without them?
They will earn both from a sort-of-a-agreement like this.
Feige has said that they have the rights for Scarlet Witch and Quicksilver, and Fox too. Marvel can use Scarlet and Quicksilver but can't say that they're mutants while Fox can use them but without saying that they're Avengers.
So, this is ok, but I suppose they can use the same actors, if they want. They can't contraddict the movies, or referenced them. But they can use the same actors.
As for Viper/Madame Hydra, i say, don't reference the Wolverine's movie but use Svetlana.