 NEW YORK--BUSINESS WIRE--Ambac Financial Group, Inc. NYSE: AMBC Ambac, a financial services holding company, today announced, consistent with its platform diversification strategy, that it has entered into an agreement to acquire 80 of the membership interests of each of Xchange Benefits, LLC and Xchange Affinity Underwriting Agency, LLC collectively, Xchange, subject to customary closing conditions. Xchange, whose management principals will retain the remaining 20 of the company, 