Pope Benedict IX

... is usually said to have had three terms in office:

The first (October 1032 – September 1044) ended in his expulsion in favour of Sylvester III;

The second (April – May 1045) ended in his selling the papacy to Gregory VI;

The third (November 1047 – July 1048) began with his return after the death of Clement II, and ended with the advent of Damasus II.