Bill Gates, Microsoft Chairman and co-chair of the Bill and Melinda Gates Foundation in a Dec. 2013 photo, in Washington, DC. Forbes says the Harvard dropout and Microsoft founder has $76 billion, more than anyone in the world.
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Carlos Slim attends a surprise party for Larry King's 80th Birthday at Dodger Stadium on Nov. 15, 2013 in Los Angeles. Slim's 4-year run as the world's richest person came to end as his business interests fell, including his ownership of Latin American telecom America Movil.
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Pablo Isla, president of Inditex and Amancio Ortega, owner of Zara, attend Rosalia Mera's funeral on August 17, 2013 in Oleiros, Spain. Ortega's wealth has skyrocketed to $64 billion based on real estate and his stake in Inditex.
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Warren Buffett speaks onstage at the FORTUNE Most Powerful Women Summit on Oct. 16, 2013 in Washington, DC. Buffett is worth $58 billion, based on his ownership of Berkshire Hathaway. He's pledged to give the bulk of his wealth to the Gates Foundation.
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Larry Ellison is honored at The Israeli Consulate Celebrates Israel's 65th Independence Day at Nobu Malibu on April 11, 2013 in Los Angeles. He's worth $48 billion based on his stake in Oracle Corp.
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Charles Koch, pictured Sept. 26, 2012, takes a moment to review some papers during a brief visit to the new Koch Cafe, an employee dining area in the Koch Industries building in Wichita, Kansas. Worth $40 billion, up $6 billion in the last year, he owns Koch Industries, the No. 2 private company in the US.
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David Koch attends the Metropolitan Opera Season Opening Production Of "Eugene Onegin" at The Metropolitan Opera House on Sept. 23, 2013 in New York City. He's the brother of Charles and also worth $40 billion. The brothers have donated hundreds of millions to conservative candidates and free-market groups.
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Philanthropist Sheldon Adelson attends the Champion Of Jewish Values International Awards Gala at The New York Marriott Marquis on June 4, 2013 in New York City. Adelson is said to be worth $38 billion.
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Producer Christy Walton attends the 28th Annual Imagen Awards at The Beverly Hilton Hotel on August 16, 2013 in Beverly Hills, Calif. She's worth $37 billion, from the wealth of dad Sam Walton, who founded Walmart.
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Jim Walton, chairman and chief executive officer of Arvest Bank Group Inc., presents the Entrepreneur Award during the Wal-Mart Stores Inc. annual shareholders meeting in Fayetteville, Arkansas, U.S., on June 7, 2013. He has $34 billion from the Walmart empire his father founded.
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