Standard & Poor’s proposed rating criteria for commercial MBS would not impact three-quarters of conduit deals but could result in upgrades for some securities and downgrades for others, according to the rating agency. Whether the proposed criteria enhancements would restore CMBS issuers’ confidence in S&P ratings is unclear, but observers say that the potential for higher ratings for some securities could pave the way for S&P to regain its exalted spot in the CMBS market. Last year, S&P shocked the market when it refused...