Investors still fuming over Facebook IPO fumbling

— -- The week that has passed since Facebook's fumbled IPO has done little to quiet the controversy and discontent surrounding the biggest IPO in financial market history.

By tumbling from their initial offering price — rather than skyrocketing, as many hoped — the current value of Facebook's shares has triggered a litany of regulatory probes and lawsuits in response to investor ire.

Investors who piled into the much-anticipated IPO and held on have suffered significant losses. Shares of the No. 1 social networking firm went public at $38 on May 18 and traded as high as $45 the first day before pulling back. Last week the pullback turned into a face plant. On Friday, a week after the stock's debut, shares were trading at $31.73, nearly 17% below the IPO price and 30% below that day's high.

Regulators, including the Securities and Exchange Commission and the Commodities Futures Trading Commission, this week have said they will look into the trading that occurred in the stock. Meanwhile, several lawsuits have been filed against the Nasdaq trading exchange as well as against Morgan Stanley, the deal's main underwriter, and Facebook CEO Mark Zuckerberg.

Specifically, three Facebook investors sued Morgan Stanley as well as other underwriting banks on the deal and Zuckerberg, alleging that Facebook's revenue estimates were reduced just prior to the IPO and allegedly only some lucky investors were informed of the change in outlook. Facebook has denied the allegations. Morgan Stanley said in an e-mailed response it conducted the IPO in compliance with the law.

Some investors may be trying to undo their involvement in the IPO and get some of their money back. Morgan Stanley is reviewing trades made by its clients and may reimburse some investors if it's determined errors by Nasdaq caused the losses, the Associated Press first reported and USA TODAY confirmed Friday.

That's a far cry from the hoopla and celebrating of the past few weeks preceding the tech giant's launch as a publicly trading company.