Facebook chairman and CEO Mark Zuckerberg (center) applauds Friday at Nasdaq’s opening bell. | FACEBOOK VIA AP

A man stops to photograph Nasdaq in Times Square as Facebook has its IPO, Friday, May 18, 2012, in New York. The social media company priced its IPO on Thursday at $38 per share, and beginning Friday regular investors will have a chance to buy shares. (AP Photo/Richard Drew)

Matts and Maria Nedermam, tourists visiting from Sweden, view Nasdaq's giant monitor as it shows a welcome message for Facebook before the company began trading on the Nasdaq stock market, Friday, May 18, 2012, in New York. (AP Photo/Bebeto Matthews)

Curious bystanders watch through the Nasdaq windows as Facebook shares begin trading, Friday, May 18, 2012 in New York. The social media company priced its IPO on Thursday at $38 per share, and beginning Friday regular investors will have a chance to buy shares. (AP Photo/Richard Drew)

Curious bystanders watch through the Nasdaq windows as Facebook shares begin trading, Friday, May 18, 2012 in New York. The social media company priced its IPO on Thursday at $38 per share, and beginning Friday regular investors will have a chance to buy shares. (AP Photo/Richard Drew)

Passers-by walk near a sign for Facebook displayed at Nasdaq, Friday, May 18, 2012, in New York. The social media company priced its IPO on Thursday at $38 per share, and beginning Friday regular investors will have a chance to buy shares. (AP Photo/Richard Drew)

The Chrysler Building is visible behind the animated facade of the Nasdaq MarketSite, welcoming the Facebook IPO, in New York's Times Square, Friday, May 18, 2012. Facebook's stock is trading up Friday, as investors seek to put a dollar value on the company that turned online social networking into a global cultural phenomenon. (AP Photo/Richard Drew)

A television photographer shoots the Like sign outside of Facebook headquarters in Menlo Park, Calif., Friday, May 18, 2012. Facebook CEO Mark Zuckerberg symbolically opened trading on the Nasdaq stock market inside Facebook headquarters in Menlo Park. Facebook stock is starting trading today, available to the general public for the first time. The social networking site, which was started in a college dorm room eight years ago, would be valued at more than $100 billion according to the price set for shares ahead of today's trading. (AP Photo/Paul Sakuma)