The Blackstone Group this week continued its expanding reach into the mortgage industry, agreeing to buy – through an affiliate – Interactive Mortgage Advisors, Denver, one of the busiest sellers of mortgage servicing rights in the nation. No purchase price was revealed. IMA is being sold through an “asset” transfer. Its trading desk affiliate, Spurs Capital, is not part of the transaction, though the two firms will maintain a working relationship. In the fourth quarter, IMA brokered...