Facebook.com is a domain owned by Facebook, Inc. Facebook.com is the world's largest social network, with more than one billion active users. Founded in 2004 by Mark Zuckerberg, the company has since entered the stock exchange as a publicly traded company, through an extremely public and debated initial public offering, resulting in a devaluation of the company's worth of up to 50%. This has been argued to have been caused by an overly presumptuous IPO. The stock has since regained some of its lost value. Facebook, Inc. acquired photo-sharing giant Instagram.com in 2012, for a value of approximately $700M in Facebook stock and cash.