Fitch Affirms 35 RMBS Classes from 6 Wells Fargo Mortgage Backed Securities

Business Wire, Nov 28, 2007

NEW YORK -- Fitch Ratings has affirmed the following six Wells Fargo Mortgage Backed Securities pass-through Certificates:

Wells Fargo 2004-AA
--Class A affirmed at 'AAA';
--Class B-1 affirmed at 'AA';
--Class B-2 affirmed at 'A';
--Class B-3 affirmed at 'BBB';
--Class B-4 affirmed at 'BB';
--Class B-5 affirmed at 'B'; removed from Rating Watch Negative.

Wells Fargo 2004-BB
--Class A affirmed at 'AAA';
--Class B-1 affirmed at 'AA';
--Class B-2 affirmed at 'A';
--Class B-3 affirmed at 'BBB';
--Class B-4 affirmed at 'BB';
--Class B-5 affirmed at 'B'.

Wells Fargo 2004-DD
--Class A affirmed at 'AAA';
--Class B-1 affirmed at 'AA ';
--Class B-2 affirmed at 'A ';
--Class B-3 affirmed at 'BBB ';
--Class B-4 affirmed at 'BB';
--Class B-5 affirmed at 'B'; removed from Rating Watch Negative.

Wells Fargo 2004-Q
--Class A affirmed at 'AAA';
--Class B-1 affirmed at 'AA';
--Class B-2 affirmed at 'A';
--Class B-3 affirmed at 'BBB';
--Class B-4 affirmed at 'BB'.

Wells Fargo 2004-W
--Class A affirmed at 'AAA';
--Class B-1 affirmed at 'AA';
--Class B-2 affirmed at 'A';
--Class B-3 affirmed at 'BBB';
--Class B-4 affirmed at 'BB';
--Class B-5 affirmed at 'B'.

Wells Fargo 2004-Z
--Class A affirmed at 'AAA';
--Class B-1 affirmed at 'AA ';
--Class B-2 affirmed at 'A ';
--Class B-3 affirmed at 'BBB ';
--Class B-4 affirmed at 'BB';
--Class B-5 affirmed at 'B'.

The affirmations reflect a satisfactory relationship between credit enhancement (CE) and future loss expectations and affect approximately $2.99 billion of outstanding certificates.

As of the October distribution date, the transactions listed above are seasoned from 34 (2004-BB and 2004-DD) to 37 (2004-Q) months. The pool factors (current principal balance as a percentage of original) range approximately from 56% (2004-W) to 68% (2004-AA).

The underlying collateral for Wells Fargo Asset Securities Corp. transactions consists of prime adjustable-rate mortgage loans secured primarily by one- to four- family residential properties. The loans have a fixed interest rate during an initial period of approximately five or seven years, after which the interest rate will adjust on an annual basis to the sum of the weekly average yield on US Treasury Securities adjusted to a constant maturity of one year and a gross margin. All of the mortgage loans were generally originated in conformity with underwriting standards of Wells Fargo Home Mortgage, Inc. (WFHM).

Wells Fargo Bank, N.A., rated 'RMS1' by Fitch, is the master servicer for all of the above transactions.

Further information regarding current delinquency, loss and credit enhancement statistics is 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.