If you are in a class action and someone is representing you, you have the right to "opt out" and bring your own action.
A lot of big entities have been opting out and bringing their own actions. Allstate and MassMutual, for instance, have mounted their own actions against the banks. AIG brought a $10 billion claim against Bank of America, stating that the bank sold it RMBS that were overvalued. The Federal Housing Finance Agency (FHFA) is suing 17 different financial institutions for misrepresenting the quality of MBS sold to Fannie Mae and Freddie Mac.