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Marc Andreessen, Andreessen Horowitz
Marc Andreessen, Andreessen Horowitz
40 under 40 rank: 1

Over 3 years: no idea. Over 30 years: up and to the right. Huge economic growth and technological progress lies ahead, both in the U.S. and globally.

NEXT: Lorenzo Simonelli, GE Transportation
Last updated October 14 2010: 6:17 AM ET
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