In a case born out of the mortgage crisis, one of the country's largest home lenders is trying to force its mortgage insurer to pay up on claims in at least 1,400 loans. Lawyers for Countrywide Home Loans want the suit in San Francisco Superior Court, but Mortgage Guaranty Insurance Corp., which wants to go to arbitration, is battling to keep the case in federal court. The suit has ping-ponged between both venues already. The stakes are sizable: Countrywide has said, in the course of opposing arbitration, that it is seeking damages of at least $150mn, according to an SEC report by MGIC this week. Originally filed in San Francisco Superior Court in December, Countrywide's complaint alleges that MGIC has "adopted unreasonable interpretations of its mortgage insurance policy language to justify its failure to pay claims."