Shares in business social networking site LinkedIn more than doubled in their public trading debut yesterday, evoking memories of the investor love affair with internet stocks during the dot-com boom of the late 1990s.
The company, which began in one man's living room less than a decade ago, is now worth more than motorcycle maker Harley Davidson and ratings company Moodys.
"I got here at 6 a.m. We've been celebrating since then," one LinkedIn employee said in the parking lot of the company's Mountain View, California headquarters.
"We recognise that there's potentially a bubble right now," said the employee, who spoke on condition of anonymity.
Shares of LinkedIn, which rose as much as 171 per cent in their first day of trade on the New York Stock Exchange, closed at $94.25 (£58), more than 109 percent above the $45 IPO price.
Bankers typically try to price an IPO so that the stock rises about 15 per cent on the first day of trading: enough to reward investors who made a bet, but not so much that the company and original shareholders feel they were short-changed.
Only days ago, LinkedIn proposed a price range for the IPO that valued it at just over $3 billion. Now, after its first day of trade, it is worth nearly $9 billion, adding to concerns that social networking company valuations are out of whack with their earnings potential.
"It seems to bring back memories of the tech bubble," said Jack Ablin, chief investment officer at Harris Private Bank in Chicago. "Based on what I know it seems like investors are a little overly enthusiastic."
One hedge fund manager who flipped his holdings in the low-80's described how difficult it was to get shares. "I got 500 shares and was told to consider myself lucky," he said.
"There are billion-dollar institutions that are not getting any stock," he said, recounting something he learned from salesperson at one of the lead banks.
Underwriters for the IPO were led by Morgan Stanley, Bank of America Merrill Lynch and JPMorgan.
LinkedIn is the first prominent US social networking company to publicly test just how hungry investors are for social media companies such as Facebook, Groupon and Twitter, which are widely expected to go public in coming months.
"It's an inevitable process for us, the next thing that happens," Facebook’s chief operating officer, Sheryl Sandberg, told the Reuters Global Technology Summit yesterday.
In recent years, only Chinese internet stocks have seen such exuberant first-day trading on US exchanges.
LinkedIn's rise was the biggest for a newly public web stock since shares of Qihoo 360 Technology, China's third most-popular internet company, rose 134 per cent in their NYSE debut in March.
LinkedIn is one of few foreign social networking companies that can operate in China, where it has about a million users. Many other sites including Twitter, Facebook and Google don't have a presence in the world's biggest internet market.
Similar to Facebook, LinkedIn allows users to create profile pages with a photo and details about themselves. But it is largely used for professional rather than social personas, and is basically an online database of electronic resumes.
The company's 2010 net income attributable to common stockholders was $3.4 million on net revenue of $243.1 million. LinkedIn has said it does not expect to be profitable in 2011.
As of 31 March, LinkedIn had 1,288 employees and 102 million registered members. As of Thursday, its market value per employee was almost $7 million and about $87 per user.