This is a good write up explaining the Falcao situation. He is mainly owned by a company run by Jorge Mendes (Ronaldo's agent) and Peter Kenyon and they helped Atletico pay for Falcao. When he gets sold next it will be for the full ownership of him and Mendes/Kenyon will pocket most of it...
http://www.reddit.com/r/soccer/comments/1e8ncw/explaining_the_falcao_move_to_monaco/
http://www.reddit.com/r/soccer/comments/1e8ncw/explaining_the_falcao_move_to_monaco/