Ambac Assurance Corp. may proceed with its fraud claims against JPMorgan Chase in connection with residential MBS that Ambac insured, a New York state judge ruled last week. In March 2012, Ambac filed suit against JPMorgan Chase, alleging fraudulent marketing of residential MBS by Bear Stearns and Co., which was acquired and renamed JPMorgan Securities. The suit claims that Ambac had to pay more than $200 million in insurance claims to investors from seven Bear Stearns securitization transactions that lost $1.8 billion. Ambac contends...