LinkedIn's second trading day pales compared with first

Although LinkedIn shares more than doubled in their Thursday debut, shares of the business-oriented site fell Friday.

On Thursday, LinkedIn shares, which trade under the symbol LNKD on the New York Stock Exchange, opened at $45 and closed at $94.25 after surging as high as $122 during trading. The Financial Times noted that at Thursday's closing price, LinkedIn was valued at $8.9 billion, making the IPO the biggest for a tech stock since Google's in 2004.

The Associated Press, citing data from Dealogic, noted that last time a U.S. company more than doubled in an IPO debut was Nymex Holdings Inc. in November 2006. Nymex, which operated the New York Mercantile Exchange, was acquired by CME Group Inc. in 2008.

On Friday, though, LinkedIn shares fell $1.16, or 1.23 percent, to close at $93.09.

The Los Angeles Times noted that trading volume for LinkedIn shares slid sharply; 8.56 million shares were traded Friday, down from 30.1 million on Thursday.

A first-day pop may not foretell solid long-term performance for a stock, MarketWatch said Friday. For example, they said, shares of Heelys, a company that makes children's sneakers that can double as skates with a weight shift, popped more than 55 percent on its debut day in December 2006 and surged more than 80 percent above its IPO price in the weeks following.

But, MarketWatch said, Heelys stock, which trades on the Nasdaq Capital Market, has since slid from its $38 level. It closed Friday at $2.21.