Lawrence Joseph "Larry" Ellison (born August 17, 1944) is an American entrepreneur and the co-founder and CEO of Oracle Corporation, the World`s largest business software company. He is currently listed on the Forbes list of billionaires as the fourth richest person in the world (as of March 11, 2009). Ellison is the third richest American, with an estimated net worth of $22.5 billion. Ellison owns 22.59% of Oracle Corporation; his shares are worth between 20 and 25 billion dollars. Ellison has been married four times. His first three marriages ended in a divorce. He was married to Adda Quinn from 1967 to 1974. He was married to Nancy Wheeler Jenkins between 1977 and 1978. From 1983 to 1986, he was married to Barbara Boothe. On 18 December 2003, Ellison married Melanie Craft, a romance novelist, at his Woodside estate. His friend Steve Jobs, Apple, Inc`s CEO, was the official wedding photographer.