Originally Posted by Zarex
Marvel Studios puts Iron Patriot in Iron Man 3, despite the thoughts of many that the Norman Osbourne alter-ego was controlled by Sony. That was followed with rumors, later confirmed of the mutants Wanda and Pietro in Avengers 2. Rumors have also surfaced of Ronan playing a role in GOTG, despite first appearing in the pages of the FF. Now FOX claims Pietro as their own, pushing back against Marvel's Phase II expansionist activities.
While this is certainly entertaining, I can see this pissing contest over IP rights ending up in the courtroom very soon.
FOX is always free to use Quicksilver in their films.