Facebook shares plunged below their offering price in trade, as early buyers sought to cut losses during the stock's first full day of trade.
The shares were down 11.25% this evening and well below the $38 initial public offering price, which made Facebook the second largest US IPO.
The tumble followed a turbulent opening trading session on Friday, which saw an early surge in Facebook shares, then a fall back to the offering price of $38.
With help from underwriters, the stock ended up slightly.
Analysts said that the action was "reminiscent of the Google IPO, which struggled out of the gate''. But they said that when ''Facebook reports second quarter numbers, likely sometime in early-to-mid July, the shares will increasingly trade on the fundamentals, not on fear''.
Other analysts said the market was unable to digest the massive amount of shares being offered, particularly with investor sentiment cautious over economic conditions and a tense situation over the euro zone and Greece.
Underwriters had expanded the Facebook offer to 421 million shares and raised the price just days before the IPO. Listings are usually preceded by an elaborate dance, as underwriters and firms try to manage expectations.
Nevertheless the eight year old company raised $16 billion in an issue which ultimately valued it at $104 billion. But with the stock plunge, the value slid to around $93 billion.
Some analysts contended that the cool response to what was billed as the hottest public stock offering in years showed that investors have learned from the folly of dot-com boom days and are gauging the social network's potential to turn its popularity into profit.
Market trackers have reported that people are much more likely to click on ads at Google than at Facebook.
Zuckerberg's post-IPO wedding is smart legal move
Getting married was a smart business move as well as a personal milestone for Facebook chief Mark Zuckerberg.
The timing of the wedding, the day after the company's initial public offering, potentially proved particularly advantageous, California divorce lawyers said.
Assuming the couple signed a prenuptial agreement, as most wealthy Californians do, Zuckerberg and Chan would have agreed exactly how to split assets, including his Facebook stock, if their marriage dissolved in future.
Even without a pre-nup, the wedding's timing would help establish the value of their assets in the event of any future divorce battle, lawyers said.
A spokeswoman for Facebook declined to comment on whether the couple signed such an agreement.
Priscilla Chan and Zuckerberg live together in the modest house in Palo Alto, where they were married on Saturday. The couple met as undergraduates at Harvard University in 2004. Zuckerberg, now 28, dropped out of college to work on Facebook, while Chan, a pediatrician, stayed to earn her undergraduage degree in 2007.
Chan's work led to Facebook creating an organ donation page. The pair recently travelled to China.
Had they continued the status quo, Chan could potentially lay claim to a much larger portion of assets, including a chunk of his $20 billion in Facebook shares, lawyers say.
"In California, people who live together without the benefit of marriage could claim they had an agreement to pool resources and efforts," said Napa lawyer Robert Blevans. Although they are hard to prove, "those claims can get really ugly."
Blevans cited the case of Anthony Maglica, the founder of the company that makes Maglite flashlights. In 1994, an Orange County court awarded $84m to Maglica's girlfriend Claire, who took his name and lived with him for 23 years. Although an appeals court reversed the award in 1998, she later negotiated a $29m settlement.
The same logic - avoiding messy court fights - enters into the calculus of a prenuptial agreement. A prenuptial agreement in California typically states how spouses would divide assets in the event of a divorce.
The couple usually waives the right to make claims based on community-property laws, which state that any property created after the marriage is essentially community property and should be split evenly after any divorce. California is one of a handful of US states with community-property laws.
Most states rely on equitable-division rules, which give more flexibility to a judge in dividing assets.
In Chan's case, she could lay claim to a portion of the options and grants in Facebook stock that vest during the time of their marriage, lawyers said. If there were no prenup, or if there were and Chan contested it, she could also try to go after stock Zuckerberg held previously if she could claim it increased in value during the relationship and the increase was due directly to Zuckerberg's efforts.
