Fitch Downgrades 2 & Affirms 1 Classes from 1 SG Mortgage Security Trust NIM Transactions

Business Wire, Oct 4, 2007

NEW YORK -- Fitch Ratings has taken the following rating actions on 1 SG Mortgage Security (SGMS) Trust Net Interest Margin (NIM) Notes:

SGMS NIM Notes, 2005-OPT1:

--$1.4 million Class I-N downgraded to 'BB' from 'BBB-';

--$0.5 million Class II-N-2 affirmed 'BBB';

--$1.6 million Class II-N-3 downgraded to 'B' from 'BBB-'.

Underlying Transaction: SG Mortgage Security Trust 2005-OPT1

The rating actions reflect actual pay-down performance of the NIM securities to date compared to initial projections, as well as, changes that Fitch previously made to its subprime loss forecasting assumptions for the underlying transactions. The updated assumptions better capture the deteriorating performance of pools from 2006 and late 2005 with regard to continued poor loan performance and home price weakness. Additional details are available in the following research, also available at www.fitchratings.com

--'U.S. Subprime RMBS/HEL Upgrade/Downgrade Criteria' (June 12, 2007);

--'Downgrade Criteria for Recent Vintage U.S. Subprime RMBS' (August 8, 2007)

--'U.S. Rating Criteria for Net Interest Margin Securitizations: Updated' (February 6, 2007).

All of Fitch's ratings criteria for US subprime RMBS available at www.fitchratings.com/subprime.> Fitch's rating definitions and the terms of use of such ratings are available on the agency's public site, www.fitchratings.com. Published ratings, criteria and methodologies are available from this site, at all times. Fitch's code of conduct, confidentiality, conflicts of interest, affiliate firewall, compliance and other relevant policies and procedures are also available from the 'Code of Conduct' section of this site.