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Facebook shares jump, then fall, then close flat

The world's largest social network starts trading on the Nasdaq and when all's said and done, the stock price ends pretty much where it started.

Facebook CEO Mark Zuckerberg -- wonder how long he was smiling today.
Facebook CEO Mark Zuckerberg has a lot to smile about today.
James Martin/CNET

Last update: 1:37 p.m. PT.

The world's largest social network is now a public company, and though it got off to a good start, the share price story for the day wasn't terribly inspiring.

Facebook today kicked off its IPO day at $38 a share, and in early trading, the company's stock jumped 12 percent to $42.50, and touched a high of $43.20.

But the shares took a startling plunge soon thereafter back to about the starting price before trending upward once again to just over $41 by early afternoon Eastern time. The Wall Street Journal reports, citing sources, that price support came from underwriters of the offering.

And then as the afternoon wore along, the share price eased down again. At the closing bell, Facebook was pretty much back where it started, ending the day at $38.23, up just 0.6 percent.

By going off at $38, Facebook was able to raise a whopping $16 billion, making it the largest Internet IPO of all time.

Facebook announced its share price yesterday. In addition, the company announced that it has sold 421.2 million shares in the offering, putting it at a valuation of $104.1 billion. By the end of the day, it's quite possible it'll boast a market capitalization that's even higher.

CNET's complete coverage: Facebook's monster IPO

In the financial world, all eyes have been on Facebook since its co-founder Mark Zuckerberg kicked off the day ringing the bell. Now, investors and analysts will be watching the social network closely to see where its shares end the day.

Editors' note: This story has been updated to reflect changes in the stock price as the day progressed.

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