Twitter CEO Dick Costolo (C) looks on during the Twitter Inc. IPO on the floor of the New York Stock Exchange in New York, November 7, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: BUSINESS ... more 
Twitter CEO Dick Costolo (C) looks on during the Twitter Inc. IPO on the floor of the New York Stock Exchange in New York, November 7, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: BUSINESS SCIENCE TECHNOLOGY) less 
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Reuters | Photo By LUCAS JACKSON / REUTERS
Thu, Nov 7, 2013 11:49 AM EST