Million-Dollar Kids: 6 Crazy Rich Teen Entrepreneurs

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Mark Bao

Mark Bao, 18, is currently a founding partner of 10 technology start-ups. In 2011, he sold his vanity app ThreeWords.me (which garnered over 17 million pageviews in a matter of a few months) to dot-com mogul Kevin Ham, whose portfolio includes around $300 million worth of domain names, for an undisclosed amount. But the amount was "very pleasing to both Bao and his parents."