A pedestrian takes a picture with his phone of a sign welcoming Facebook at the NASDAQ stock exchange on Times Square in New York, on May 18, 2012. Facebook began testing the feasibility of charging

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A pedestrian takes a picture with his phone of a sign welcoming Facebook at the NASDAQ stock exchange on Times Square in New York, on May 18, 2012. Facebook began testing the feasibility of charging to guarantee that messages from strangers make it into inboxes of intended recipients at the social network.

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