In an 8-K filed with the SEC on November 18, 2010, Ambac Assurance Corporation announced that it is conducting a review of the mortgage loans underlying a dozen Ambac-insured RMBS, in addition to 17 RMBS as to which it already has initiated litigation.  Ambac stated that it intends to perform what it describes as forensic analysis of the loan origination files and processes and a “re-underwriting” of the loans to determine whether there were breaches of the representations and warranties made at the time the securities were issued.  Ambac also stated that it has either sought or intends to seek the repurchase of certain loans underlying the RMBS due to claimed breaches of representations and warranties.  Form 8-K.