Steve Ballmer, Microsoft
Ballmer, 57, is the only one on this list that did not start or co-found the company to which he's associated with. Ballmer joined Microsoft as its 30th employee in June 1980, and went on to head several divisions, including operations, operating systems development, and sales and support, until he became CEO of the company in January 2000, officially replacing Gates.
Since then, Microsoft has underground a rocky relationship with the press, its shareholders and the tech world in general, which has seen Microsoft as something of a dinosaur which relies on its cash cows, Windows and Office, but coming up with little else to show for its efforts.
Ballmer stepped down as CEO earlier this year, being replaced by the aforementioned Nadella, but not before he amassed an estimated personal net worth of $19.3 billion, good enough for No. 36 on the overall list.