There is a clause that ties Vettel to Red Bull also in 2012

A results clause suggests that the German is unlikely to leave Red Bull at the end of 2011. After becoming the youngest world champion in F1 history, Vettel's move to Ferrari has been indicated as very likely.

Seb is under contract for 2011, and the 2012 option was thought to be exercisable by both the driver and the Austrian team.
However, in an article published in the Red Bull magazine, Speed ​​Week, we read that if Vettel wins a pre-established number of races, and finishes the world championship among the top three, he will also be blocked for 2012.
The editorial specifies that everything said about the German's future beyond 2011 "was written without knowing his contractual situation".
Helmut Marko confirms: “There is a clause linked to results. We won't just let a top driver walk away."

Filippo Ronchetti