Twitter Prices Shares at $26 Apiece

The stock will begin trading under the ticker symbol "TWTR" on Thursday.

Twitter, a social-media company that lost $137 million in the past 12 months, will be valued at $18 billion when its stock begins trading on the New York Stock Exchange after the company said late Wednesday it has priced its initial public offering at $26 a share.

Twitter's IPO involves the sale of 70 million shares for $1.8 billion. Beginning Thursday, the stock will trade under the ticker symbol, "TWTR."

Twitter began seven years ago as a way for users to blast short messages to one another, and it has grown to 232 million users who tweet 500 million times per day.

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As Twitter has grown, celebrities have grown fond of the service and use it to deepen their connection to their fans. Ashton Kutcher boasted he was the first person to reach 1 million followers, and just this week Katy Perry surpassed Justin Bieber as the most popular person on Twitter, with 46,564,181 followers.

Twitter's IPO is the most high-profile since Facebook raised $16 billion by going public at $38 a share last year. Facebook shares famously flopped in the weeks and months after they first started trading, though patient investors were eventually rewarded and shares closed Wednesday at $49.12.