State attorneys general trying to negotiate a big-ticket settlement with top mortgage servicers saw their coalition fracture further over the past week, including a decision by Massachusetts to move independently toward litigation. A major stumbling block continues to be divergent views among the states on whether lenders should get immunity from non-servicing issues such as potential litigation over securitization as part of the deal. The widely held view is that top banks were willing to put up a combined $20 billion to be used to help struggling borrowers to settle legal challenges that were spawned by...