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Facebook IPO

A sign welcoming Facebook is flashed on a screen outside the NASDAQ stock exchange at Times Square in New York, May 18, 2012. Facebook is set to go public on May 18, 2012 and is likely to have an estimated market valuation of over $100 billion when its shares begin trading on the NASDAQ. (credit: EMMANUEL DUNAND/AFP/GettyImages)

Facebook Now Worth More Than, McDonalds In Public Debut

With its debut on the stock market Friday, Facebook has become the most valuable U.S. company to ever go public.