A federal appeals court unanimously rejected a claim by one Facebook shareholder that "lock-up" agreements forbade Goldman Sachs, JPMorgan Chase and Morgan Stanley from trading Facebook shares soon after the May 2012 initial public offering.  The basis of the claim was that the banks and selling shareholders together formed a "group" owning more than 10% of the social media company's stock.

As a result, the 3 investment banks need not forfeit their estimated $100 million of trading profits.

The lawsuit was one of dozens targeting Facebook, the banks and others after the $16 billion IPO suffered from technical glitches and its stock price slid 54% within 4 months.

Thursday’s ruling upheld U.S. District Judge Robert Sweet’s dismissal of the lawsuit. Judge Sweet said the lock-up agreements restricting insiders from selling stock were standard in the industry; Circuit Judge Ralph Winter, who sat on the panel, said subjecting bank underwriters to similar restrictions would "complicate" their role, add millions of dollars of legal exposure and reduce the number of companies going public.