Together with his college roommates and fellow Harvard University students Eduardo Saverin, Andrew McCollum, Dustin Moskovitz, andChris Hughes, he launched Facebook from Harvard University's dormitory rooms. The group then introduced Facebook onto other campuses nationwide and moved to Palo Alto, California shortly afterwards. In 2007, at the age of 23, Zuckerberg became a billionaire as a result of Facebook's success. The number of Facebook users worldwide reached a total of one billion in 2012. Zuckerberg was involved in various legal disputes that were initiated by others in the group, who claimed a share of the company based upon their involvement during the development phase of Facebook