Richest people on the planet 2015

Published On: Mar 08 2012 09:56:15 AM CST   Updated On: Mar 02 2015 09:37:33 AM CST

A familiar face once again tops Forbes' list of the world's richest billionaires.

David Koch
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6. David Koch (tie) -- The billionaire is co-owner (with older brother Charles) and an executive vice president of Koch Industries, a conglomerate that is the second-largest privately held company in the U.S. He's worth an estimated $42.9 billion.

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