Mark Elliot Zuckerberg (born May 14, 1984) is an American computer programmer and Internet entrepreneur. He is a co-founder of Facebook, and currently operates as its chairman and chief executive officer. His net worth is estimated to be US$63.3 billion as of May 2017, and he is ranked by Forbes as the fifth richest person in the world. Zuckerberg launched Facebook from his Harvard University dormitory room on February 4, 2004. He was assisted by his college roommates and fellow Harvard students Eduardo Saverin, Andrew McCollum, Dustin Moskovitz, and Chris Hughes. The group then introduced Facebook to other college campuses. Facebook expanded rapidly, reaching one billion users by 2012. Meanwhile, Zuckerberg was involved in various legal disputes brought by others in the group, who claimed a share of the company based upon their involvement during the development phase of Facebook. In December 2012, Zuckerberg and his wife Priscilla Chan announced that over the course of their lives they would give the majority of their wealth to "advancing human potential and promoting equality" in the spirit of The Giving Pledge. On December 1, 2015, they announced they would eventually give 99 percent of their Facebook shares (worth about US$45 billion at the time) to the Chan Zuckerberg Initiative. Since 2010, Time magazine has named Zuckerberg among the 100 wealthiest and most influential people in the world as a part of its Person of the Year award. In December 2016, Zuckerberg was ranked 10th on Forbes list of The World's Most Powerful People.