Fitch Takes Various Rating Actions on 4 Option One NIM Notes

Business Wire, May 28, 2008

NEW YORK -- Fitch Ratings has taken the following rating actions on 4 Option One Net Interest Margin (NIM) Notes:

Option One Mortgage Securities Corp. NIM Trust 2005-1

--$2.5 million Class notes affirmed at 'AAA';

Underlying Transaction: Option One 2005-1

Option One CI 4 NIM Notes, Series 2005-3

--$3.4 million Class N-1 notes downgraded to 'C/DR6' from 'BBB ';

--$4.0 million Class N-2 notes downgraded to 'C/DR6' from 'BBB-';

Underlying Transaction: Option One 2005-3

Option One Mortgage Securities Corp. NIM Trust 2006-1

--$34.2 million Class notes affirmed at 'AAA';

Underlying Transaction: Option One 2005-4

Option One Mortgage Securities Corp. NIM Trust 2007-FXD1 Notes

--$5.0 million Class notes affirmed at 'AAA';

Underlying Transaction: Option One Mortgage Loan Trust 2007-FXD1

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.

Additional details are available in the following research, available at www.fitchratings.com:

--'Fitch Places $139B U.S. Subprime RMBS On Watch Negative on Worsening Mortgage Performance' (Feb. 1, 2008);

--'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.