BMW sold its share of BMW Sauber back to Peter Sauber after the end of the 2009 season .
Having not won a Grand Prix as an independent , the team was sold to BMW in 2005 , and competed as BMW Sauber from 2006 to 2009 , scoring one victory . At the end of the 2009 season , however , BMW pulled out of Formula One and the team 's future remained uncertain for several months , until it was sold back to Peter Sauber and granted a 2010 entry .