CFO, ArcelorMittal Despite being the son of ArcelorMittal's founder, Mittal, 35, worked his way up to CFO of the steel company in 2004. He orchestrated the $38 billion takeover of Arcelor, reduced corporate debt, and is helping execute an ambitious expansion plan. Mittal is a well-rounded executive who has the CEO's ear -- and not just because he's a relative.
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