Facebook shares jump 15.5 percent after strong results

Facebook Inc (FB.O) shares surged 15.5 percent on Thursday, their biggest percentage increase since July 2013, after the social networking service posted quarterly results that blew away expectations on every key measure.

Facebook shares closed at $109.11, putting its market capitalization at about $308.6 billion. That would make it the fourth most valuable technology company, overtaking Amazon.com Inc (AMZN.O), which was valued at about $296 billion ahead of its results on Thursday.

Facebook's strong quarter contrasted with a disappointing performance by Apple Inc (AAPL.O), which is worth about $519 billion, making it the most valuable U.S. company.