CFO, UnitedHealth Group
Age: 39
Rank change: New
Industry: Health care
Minnesota native Mikan worked at Arthur Andersen before joining the country's biggest insurer in 1998. Since then, UnitedHealth Group has grown its revenue from $17 billion to nearly $90 billion -- in part because of Mikan's work as the head of M&A, in which he led over 100 transactions. When UnitedHealth got hit with options-backdating charges in 2006, the company cleaned house and installed Mikan as its new CFO. In 2008, Mikan joined the board of Best Buy.
Pedigree: Mikan's grandfather George Mikan was a 6-foot-10 basketball star who played for the Minneapolis Lakers.
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Last updated October 14 2010: 1:25 PM ET