With a tweet, Twitter kicks off next big tech IPO

Twitter said Thursday that it filed for an initial public offering, setting the stage for the most high-profile technology stock market debut since Facebook's troubled share sale last year. Twitter announced the filing on its own social media messaging service, saying: "We've confidentially submitted an S-1 to the SEC for a planned IPO. This Tweet does not constitute an offer of any securities for sale." The company followed that up with a second tweet, saying "back to work" and attached a photo of employees at Twitter headquarters in San Francisco. The tweets were swiftly re-tweeted thousands of times and set off viral chatter across Silicon Valley, where many of the venture capitalists who backed Twitter are based. George Zachary of Charles River Ventures thanked Twitter founders Jack Dorsey, Evan Williams and Biz Stone and CEO Dick Costolo. "Still hold every single share from our first-round investment," Zachary tweeted. "My over/under for Twitter at end of first day of trading: $25B," tweeted David Sacks, a former PayPal executive and founder of start-up Yammer, which Microsoft bought for $1.2 billion last year. "This is one of those exciting moments in the Valley," said Kevin Hartz, CEO of start-up Eventbrite, who has invested in several other successful start-ups including PayPal, Pinterest and Airbnb. "It's just a financing event for Twitter, but it does demonstrate the next step in the life of what is an emerging Internet giant." Twitter, created in 2006, has turned into a new form of communication used by presidents, corporate chieftains and smartphone-wielding kids alike. The company has only recently started to generate serious revenue by showing ads in the stream of other tweets users see. But these initiatives have gained traction: Twitter will haul in $583 million in advertising revenue for 2013 and hit $1 billion in 2014, according to eMarketer. "It makes sense that they are doing an IPO with those numbers. It's a great time for them to raise money," says Gartner analyst Brian Blau. The filing is also timed as the fourth quarter approaches — a traditionally strong period for social media activity and related advertising, according to Sam Schwerin of Millennium Technology Value Partners, which owns a small stake in Twitter.