The lawsuit alleges that Facebook executives, including Zuckerberg, CFO David Ebersman, company board members, underwriter Morgan Stanley and others intentionally hid negative views of the company's revenue growth potential prior to last week's IPO.
Facebook officials and its investors could have cause for concern as the lawsuit was filed by Robbins Geller Rudman & Dowd LLP, a San Diego-based law firm that won $7 billion for Enron shareholders from the energy firm's investors.
"[Depending] on how this plays out, it could be a big deal if they did something wrong," said Zeus Kerravala, an analyst at ZK Research. "We live in such a litigious society that if they are found having hidden information, they could wind up paying out millions of dollars."
He added that the lawsuit, along with Facebook's already flagging share price, is a big distraction for Facebook executives. "It takes away from running the business," Kerravala said.
On top of the lawsuit, the IPO also is reportedly being investigated by the US Securities and Exchange Commission and the Financial Industry Regulatory Authority, an independent securities regulator.
Eyebrows were initially raised last Friday when the Facebook's shares failed to hit $50 to $90 a share last Friday after the IPO as some experts had expected. The first day of trading instead ended with a stock price just slightly above it's $38 offer price.
On Monday, the share price sunk to about $34, and then declined a few dollars more yesterday.
Concerns about the offering were further raised late Monday when Reuters reported that analysts at Morgan Stanley, the lead underwriter for the IPO, had cut their Facebook revenue forecasts without informing most investors.
The lawsuit notes that 421 million shares of Facebook sold in the IPO. Earlier today, shares were trading for around $31 per share.
"While defendants pocketed billions of dollars ... plaintiffs and the Class have suffered losses of more than $2.5 billion since the IPO," the legal complaint alleges.
In the months before Facebook's IPO, there was mounting excitement that reached something of a frenzy early last week. Facebook's name filled newspaper and online headlines and was the talk on television newsrooms and around office break rooms.
At the same time, the company did take a few stumbles in the days leading up to the IPO.
For instance, Zuckerberg was publicly chastised for wearing jeans and a hoodie sweatshirt during a presentation to buttoned-down Wall Street investors. His casual appearance left some wondering whether the 28-year-old had the maturity to run a major public company.
And as questions arose about Facebook's abilityto monetise its growing base of mobile users, General Motors pulled plans for a major ad buy, explaining that its advertising on Facebook wasn't working as expected.
The lawsuit, the SEC investigation and all the bad press "will hurt the firm's image massively and may force a change at the top," said Rob Enderle, an analyst with the Enderle Group, who suggested that Facebook hire a professional disaster management team.