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Young Money: Billionaires Under 40

Facebook execs, Under Armour founder among world's richest young people.

Billionaires Under 40: Facebook Execs, Under Armour Founder

Young Money
Young Money
Young Money
Young Money
Young Money
Young Money
Young Money
Young Money
Young Money
Young Money
Young Money
Young Money
Even though his net worth is $17.5 billion, Mark Zuckerberg, the founder and CEO of Facebook Inc., still gives presentations in t-shirts and jeans. In 2011, The Economist named the 27-year-old New York native the world's wealthiest person, when adjusted for age. Zuckerberg has control of 56.9 percent of Facebook's total pre-IPO voting power, according to Forbes. (David Paul Morris/Bloomberg/Getty Images)
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