Fitch Rates $1B IndyMac Home Equity Mtge Loan Asset-Backed Trust INABS 2007-B.

NEW YORK -- Fitch rates IndyMac Home Equity Mortgage Loan Asset-Backed Trust, series INABS 2007-B, as follows:

--$739,999,000 classes 1A-1, 1A-2 and 2A-1 through 2A-4, 'AAA';

--$55,500,000 class M-1 'AA+';

--$52,000,000 class M-2 'AA';

--$14,000,000 class M-3 'AA-';

--$17,500,000 class M-4 'A+';

--$16,500,000 class M-5 'A';

--$8,500,000 class M-6 'A-';

--$13,500,000 class M-7 'BBB+';

--$11,000,000 class M-8 'BBB';

--$14,500,000 class M-9 'BBB-';

--$16,500,000 class M-10 'BB+';

--$16,000,000 non-offered class M-11 'BB'.

The 'AAA' rating on the senior certificates reflects the 26% total credit enhancement provided by the 5.55% class M-1, 5.20% class M-2, 1.40% class M-3, 1.75% class M-4, 1.65% class M-5, 0.85% class M-6, 1.35% class M-7, 1.10% class M-8, 1.45% class M-9, 1.65% class M-10, 1.60% non-offered class M-11, and 2.45% initial overcollateralization (OC). All certificates have the benefit of monthly excess cash flow to absorb losses. In addition, the ratings reflect the integrity of the transaction's legal structure as well as the capabilities of IndyMac Bank, F.S.B. (rated 'RPS2+' by Fitch) as a servicer and Deutsche Bank National Trust Company (rated 'AA-/F1+' by Fitch) as a trustee.

The certificates are supported by two groups of mortgage loans. The aggregate mortgage pool consists of first and second lien fixed- and adjustable-rate mortgage loans with a closing date pool balance of approximately $900 million. On the closing date, the depositor will deposit approximately $100 million into a pre-funding account. The amount in this account will be used to purchase subsequent mortgage loans after the closing date and on or prior to June 29, 2007.

IndyMac MBS, Inc., the depositor, purchased the mortgage loans from IndyMac Bank, F.S.B., the mortgage loan seller, and caused the mortgage loans to be assigned to the trustee for the benefit of holders of the certificates. For federal income tax purposes, an election will be made to treat the trust fund as multiple real estate mortgage investment conduits (REMICs).

For more information, please see the new issue report titled 'Home Equity Mortgage Loan Asset-Backed Trust, Series INABS 2007-B', available on the Fitch Ratings web site at www.fitchratings.com.

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.