NEW YORK -- Fitch rates HarborView Mortgage Loan Trust 2005-15 mortgage loan pass-through certificates as follows:

-- $874.2 million class 1-A1A, 1-A1B, 2-A1A through 2-A1C, 3-A1A through 3-A1C, PO-1, PO-2, PO-3A, PO-3B, PO-B and A-R 'AAA';

-- $16.1 million class B-1 'AA+';

-- $14.6 million class B-2 'AA+';

-- $10.2 million class B-3 'AA';

-- $7.3 million class B-4 'AA';

-- $7.3 million class B-5 'A+';

-- $5.8 million class B-6 'A';

-- $6.8 million class B-7 'A-';

-- $4.8 million class B-8 'BBB+';

-- $3.9 million class B-9 'BBB';

-- $5.8 million class B-10 'BBB-'.

The class B-11 and B-12 are not rated by Fitch.

The 'AAA' ratings on the class 1-A1A, 1-A1B, 2-A1A through 2-A1C, 3-A1A through 3-A1C, PO-1, PO-2, PO-3A, PO-3B, PO-B, and A-R certificates are based on the 10.55% credit enhancement provided by the 1.65% class B-1, 1.50% class B-2, 1.05% class B-3, 0.75% class B-4, 0.75% class B-5, 0.60% class B-6, 0.70% class B-7, 0.50% class B-8, 0.40% class B-9, 0.60% class B-10, 1.40% class B-11, and 0.65% class B-12. The ratings on the classes B-1 through B-10 certificates are based on their respective subordination.

Fitch believes the above credit enhancement will be adequate to support mortgagor defaults. In addition, the ratings reflect the quality of the mortgage collateral, strength of the legal and financial structures, the servicing capabilities of GMAC Mortgage Corporation (rated 'RPS1' by Fitch) and Washington Mutual Bank (rated 'RPS2' by Fitch) as servicers and Wells Fargo Bank, N.A. (rated 'RMS1' by Fitch) as master servicer.

The trust comprises three cross-collateralized groups of 2,392 conventional first lien mortgage loans with an aggregate principal balance of $977,380,312. The collateral was primarily originated by Paul Financial, LLC (24.30%) and Secured Bankers Mortgage Company (13.16%). The mortgage loans are adjustable-rate mortgages (ARMs) with the potential to negatively amortize, commonly known as Option ARMs. The Option ARM borrowers have four payment options: interest only (IO), minimum monthly payment (MMP), principal and interest payment based on a 15-year amortization schedule, and principal and interest payment based on a 30-year amortization schedule. The loans may negative amortize if the borrower chooses to make the MMP particularly in a rising rate environment. The Option ARMs are indexed to the 12-month moving average U.S. Treasury index (MTA) plus a spread.