Prime Jumbo RMBS Classes Downgraded

Four classes from three U.S. prime jumbo residential mortgage-backed securities deals issued from 2004 to 2006 have been downgraded by Standard & Poor's Ratings Services. The downgrades were as follows: Structured Asset Mortgage Investments II Trust, class B-4, from B to CCC, and class B-5, from CCC to D; and Structured Adjustable Rate Mortgage Loan Trust series 2005-21, class B9-I, from CC to D, and series 2006-7, class B5-II, from CC to D. The three classes that were assigned a default rating suffered principal writedowns and are not expected to receive their full principal balance, S&P said. The other downgrade reflects "negative projected credit support due to high delinquencies and adverse collateral performance," the rating agency said.