9 richest billionaires of 2013

5. Charles G. Koch, 76 Company: Koch Industries Net worth: $24.7 billion Compensation: N/A Charles G. Koch has been the chairman and CEO of Koch Industries — one of the largest privately owned companies in the U.S. — since 1967. The group’s annual revenue is more than $100 billion, according to Forbes. Koch Industries was co-founded by Charles’s father Fred C. Koch and classmate Lewis E. Winkler in 1925 as Winkler-Koch Engineering. The company developed an innovative cracking method of turning crude oil into gasoline. After the death of Fred Koch in 1967, sons Charles and David Koch, both engineers, took control of the Kansas-based mid-size firm and expanded the Koch empire globally to have a presence in 60 countries with interests in energy, textiles, petrochemicals and pulp and paper. Koch Industries is considered among the world’s top independent oil traders by turnover. Charles Koch’s stake in the group is estimated to be at least $22.4 billion, according to Wealth-X. Other big assets include his homes in Aspen, Colorado and Indian Wells, California, which are estimated to be worth $7 million and $5 million respectively. The Koch brothers are known for their activism on conservative causes. The duo has been pumping millions of dollars into libertarian groups and political campaigns of right-wing politicians and candidates since the 1960s. In 2011, the brothers were named among the 100 most influential people in the world by Time Magazine, largely due to their financial support for Tea Party causes. Photo: John Chiasson | Liaison | Getty Images