#10 Michael Bloomberg
With a fortune of just under $44 billion, Bloomberg was born in February 1942. An keen politician, philanthropist and author, this American businessman is the founder and ceo of Bloomberg L.P. Having served as the Mayor of New York City for 3 consecutive terms, Bloomberg was considered as a possible candidate for the last 3 USA presidential elections. While there was widespread speculation that he would run as a third candidate in the 2016 elections, he decided not to and went on to endorse Hillary Clinton.
#8 (Joint) David Koch
Born in May 1940 and younger brother to Charles Koch, joined the family business in 1970 and went on to become co-owner of Kock Industries in 1983. With a current net worth of over $44 billion he is the equal 8th richest person on the planet. An influential libertarian, Koch was their 1980 candidate for vice president of the USA and is a survivor of the ASAir Flight 1493 crash in 1991.