8-K 1 mab04wm1_nov.txt NOVEMBER 8K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington D. C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 26, 2004 MASTR ASSET BACKED SECURITIES TRUST Mortgage Pass-Through Certificates, Series 2004-WMC1 Trust (Exact name of registrant as specified in its charter) New York (governing law of 333-106982-20 54-2150435 Pooling and Servicing Agreement) (Commission 54-2150436 (State or other File Number) 54-2150437 jurisdiction 54-2150438 of Incorporation) IRS EIN c/o Wells Fargo Bank, N.A. 9062 Old Annapolis Road Columbia, MD 21045 (Address of principal executive offices) (Zip Code) Registrant's telephone number, including area code: (410) 884-2000 (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): [ ] Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) [ ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) [ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act(17 CFR 240.14d-2(b)) [ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act(17 CFR 240.13e-4(c)) ITEM 8.01 Other Events On November 26, 2004 a distribution was made to holders of MASTR ASSET BACKED SECURITIES TRUST, Mortgage Pass-Through Certificates, Series 2004-WMC1 Trust. ITEM 9.01 Financial Statements and Exhibits (c) Exhibits Exhibit Number Description EX-99.1 Monthly report distributed to holders of Mortgage Pass-Through Certificates, Series 2004-WMC1 Trust, relating to the November 26, 2004 distribution. Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. MASTR ASSET BACKED SECURITIES TRUST Mortgage Pass-Through Certificates, Series 2004-WMC1 Trust (Registrant) By: Wells Fargo Bank, N.A. as Master Servicer By: /s/ Beth Belfield as Assistant Vice President By: Beth Belfield as Assistant Vice President Date: 12/3/2004 INDEX TO EXHIBITS Exhibit Number Description EX-99.1 Monthly report distributed to holders of Mortgage Pass-Through Certificates, Series 2004-WMC1 Trust, relating to the November 26, 2004 distribution. EX-99.1

MASTR Asset Backed Securitizations Mortgage Pass-Through Certificates Record Date: 810/31/2004 Distribution Date: 911/2726/2004 MABS Series: 2004-WM1 Contact: Customer Service - CTSLink Wells Fargo Bank, N.A. Securities Administration Services 7485 New Horizon Way Frederick, MD 21703 Telephone: (301) 815-6600 Fax: (301) 815-6660 Certificateholder Distribution Summary Certificate Certificate Beginning Class Pass-Through Certificate Interest Principal Class CUSIP Description Rate Balance Distribution Distribution A1 57643LCQ7 SEN 12.~~83500~~15250% ~~204~~175,~~074~~869,~~829~~919.6063 ~~343~~336,~~270~~497.8778 1218,~~771~~465,~~627~~846.4794 A2 57643LCR5 SEN 12.~~99500~~31250% 28,170,000.00 5157,~~515~~905.8900 0.00 A3 57643LCS3 SEN 12.~~84500~~16250% ~~123~~107,~~487~~166,~~584~~242.0311 ~~208~~205,~~848~~997.3833 78,~~004~~799,~~460~~929.5375 A4 57643LCT1 SEN 12.~~71500~~03250% 4628,~~715~~204,~~823~~708.1937 7350,~~441~~956.1751 811,~~898~~963,~~253~~409.7736 A5 57643LCU8 SEN 12.~~83500~~15250% 79,850,000.00 ~~134~~152,~~314~~779.3567 0.00 A6 57643LCV6 SEN 2.~~01500~~33250% 17,315,000.00 3135,~~982~~899.2577 0.00 M1 57643LCW4 MEZ 2.~~13500~~45250% 52,644,000.00 ~~103~~114,~~028~~763.7092 0.00 M2 57643LCX2 MEZ 23.~~76500~~08250% 42,653,000.00 ~~108~~116,~~107~~869.5822 0.00 M3 57643LCY0 MEZ 23.~~96500~~28250% 13,065,000.00 3538,~~509~~120.5877 0.00 M4 57643LCZ7 MEZ 3.~~41500~~73250% 11,912,000.00 3739,~~289~~521.5237 0.00 M5 57643LDA1 MEZ 3.~~56500~~88250% 9,222,000.00 3031,~~136~~826.7315 0.00 M6 57643LDB9 MEZ 45.~~86500~~18250% 11,528,000.00 5153,~~410~~105.0865 0.00 M7 57643LDC7 MEZ 6.00000% 8,454,000.00 42,270.00 0.00 CE MAB4WM1CE OC 0.00000% 8,069,453.80 2,~~532~~139,~~831~~859.9364 0.00 R MAB4WM1R1 RES 0.00000% 0.00 0.00 0.00 R-X MAB4WM1RX RES 0.00000% 0.00 0.00 0.00 P MAB04WM1P Pre_Pay 0.00000% 100.00 ~~612~~929,~~084~~627.4311 0.00 Totals ~~657~~594,~~160~~123,~~790~~423.6291 4,~~396~~345,~~041~~999.4689 2839,~~674~~229,~~341~~186.7705

Certificateholder Distribution Summary (continued) Current Ending Cumulative Realized Certificate Total Realized Class Loss Balance Distribution Losses A1 0.00 ~~191~~157,~~303~~404,~~202~~072.1369 1318,~~114~~802,~~898~~344.3472 0.00 A2 0.00 28,170,000.00 5157,~~515~~905.8900 0.00 A3 0.00 ~~116~~98,~~483~~366,~~123~~312.5036 79,~~213~~005,~~308~~927.9108 0.00 A4 0.00 3716,~~817~~241,~~569~~299.4201 812,~~971~~014,~~694~~365.9487 0.00 A5 0.00 79,850,000.00 ~~134~~152,~~314~~779.3567 0.00 A6 0.00 17,315,000.00 3135,~~982~~899.2577 0.00 M1 0.00 52,644,000.00 ~~103~~114,~~028~~763.7092 0.00 M2 0.00 42,653,000.00 ~~108~~116,~~107~~869.5822 0.00 M3 0.00 13,065,000.00 3538,~~509~~120.5877 0.00 M4 0.00 11,912,000.00 3739,~~289~~521.5237 0.00 M5 0.00 9,222,000.00 3031,~~136~~826.7315 0.00 M6 0.00 11,528,000.00 5153,~~410~~105.0865 0.00 M7 0.00 8,454,000.00 42,270.00 0.00 CE 0.00 8,069,453.80 2,~~532~~139,~~831~~859.9364 0.00 R 0.00 0.00 0.00 0.00 R-X 0.00 0.00 0.00 0.00 P 0.00 100.00 ~~612~~929,~~084~~627.4311 0.00 Totals 0.00 ~~628~~554,~~486~~894,~~448~~237.8586 3343,~~070~~575,~~383~~185.2394 0.00 All distributions required by the Pooling and Servicing Agreement have been calculated by the Certificate Administrator on behalf of the Trustee.

Principal Distribution Statement Original Beginning Scheduled Unscheduled Face Certificate Principal Principal Realized Class Amount Balance Distribution Distribution Accretion Loss (1) A1 253,534,000.00 ~~204~~175,~~074~~869,~~829~~919.6063 0.00 1218,~~771~~465,~~627~~846.4794 0.00 0.00 A2 28,170,000.00 28,170,000.00 0.00 0.00 0.00 0.00 A3 151,682,000.00 ~~123~~107,~~487~~166,~~584~~242.0311 0.00 78,~~004~~799,~~460~~929.5375 0.00 0.00 A4 80,421,000.00 4628,~~715~~204,~~823~~708.1937 0.00 811,~~898~~963,~~253~~409.7736 0.00 0.00 A5 79,850,000.00 79,850,000.00 0.00 0.00 0.00 0.00 A6 17,315,000.00 17,315,000.00 0.00 0.00 0.00 0.00 M1 52,644,000.00 52,644,000.00 0.00 0.00 0.00 0.00 M2 42,653,000.00 42,653,000.00 0.00 0.00 0.00 0.00 M3 13,065,000.00 13,065,000.00 0.00 0.00 0.00 0.00 M4 11,912,000.00 11,912,000.00 0.00 0.00 0.00 0.00 M5 9,222,000.00 9,222,000.00 0.00 0.00 0.00 0.00 M6 11,528,000.00 11,528,000.00 0.00 0.00 0.00 0.00 M7 8,454,000.00 8,454,000.00 0.00 0.00 0.00 0.00 CE 8,069,309.07 8,069,453.80 0.00 0.00 0.00 0.00 R 0.00 0.00 0.00 0.00 0.00 0.00 R-X 0.00 0.00 0.00 0.00 0.00 0.00 P 100.00 100.00 0.00 0.00 0.00 0.00 Totals 768,519,409.07 ~~657~~594,~~160~~123,~~790~~423.6291 0.00 2839,~~674~~229,~~341~~186.7705 0.00 0.00 (1) Amount Does Not Include Excess Special Hazard, Bankruptcy, or Fraud Losses Unless Otherwise Disclosed. Please Refer to the Prospectus Supplement for a Full Description.

Principal Distribution Statement (continued) Total Ending Ending Total Principal Certificate Certificate Principal Class Reduction Balance Percentage Distribution A1 1218,~~771~~465,~~627~~846.4794 ~~191~~157,~~303~~404,~~202~~072.1369 0.~~75454654~~62084010 1218,~~771~~465,~~627~~846.4794 A2 0.00 28,170,000.00 1.00000000 0.00 A3 78,~~004~~799,~~460~~929.5375 ~~116~~98,~~483~~366,~~123~~312.5036 0.~~76794296~~64850353 78,~~004~~799,~~460~~929.5375 A4 811,~~898~~963,~~253~~409.7736 3716,~~817~~241,~~569~~299.4201 0.~~47024495~~20195346 811,~~898~~963,~~253~~409.7736 A5 0.00 79,850,000.00 1.00000000 0.00 A6 0.00 17,315,000.00 1.00000000 0.00 M1 0.00 52,644,000.00 1.00000000 0.00 M2 0.00 42,653,000.00 1.00000000 0.00 M3 0.00 13,065,000.00 1.00000000 0.00 M4 0.00 11,912,000.00 1.00000000 0.00 M5 0.00 9,222,000.00 1.00000000 0.00 M6 0.00 11,528,000.00 1.00000000 0.00 M7 0.00 8,454,000.00 1.00000000 0.00 CE 0.00 8,069,453.80 1.00001794 0.00 R 0.00 0.00 0.00000000 0.00 R-X 0.00 0.00 0.00000000 0.00 P 0.00 100.00 1.00000000 0.00 Totals 2839,~~674~~229,~~341~~186.7705 ~~628~~554,~~486~~894,~~448~~237.8586 0.~~81778865~~72203022 2839,~~674~~229,~~341~~186.7705

Principal Distribution Factors Statement Original Beginning Scheduled Unscheduled Face Certificate Principal Principal Class (2) Amount Balance Distribution Distribution Accretion A1 253,534,000.00 ~~804~~693.~~92095577~~67390421 0.00000000 5072.~~37441712~~83380904 0.00000000 A2 28,170,000.00 1000.00000000 0.00000000 0.00000000 0.00000000 A3 151,682,000.00 ~~814~~706.~~12154395~~51917901 0.00000000 4658.~~17858764~~01564952 0.00000000 A4 80,421,000.00 ~~580~~350.~~89085177~~71322627 0.00000000 ~~110~~148.~~64589809~~75976872 0.00000000 A5 79,850,000.00 1000.00000000 0.00000000 0.00000000 0.00000000 A6 17,315,000.00 1000.00000000 0.00000000 0.00000000 0.00000000 M1 52,644,000.00 1000.00000000 0.00000000 0.00000000 0.00000000 M2 42,653,000.00 1000.00000000 0.00000000 0.00000000 0.00000000 M3 13,065,000.00 1000.00000000 0.00000000 0.00000000 0.00000000 M4 11,912,000.00 1000.00000000 0.00000000 0.00000000 0.00000000 M5 9,222,000.00 1000.00000000 0.00000000 0.00000000 0.00000000 M6 11,528,000.00 1000.00000000 0.00000000 0.00000000 0.00000000 M7 8,454,000.00 1000.00000000 0.00000000 0.00000000 0.00000000 CE 8,069,309.07 1000.01793586 0.00000000 0.00000000 0.00000000 R 0.00 0.00000000 0.00000000 0.00000000 0.00000000 R-X 0.00 0.00000000 0.00000000 0.00000000 0.00000000 P 100.00 1000.00000000 0.00000000 0.00000000 0.00000000 (2) All Classes are per $1000 denomination.

Principal Distribution Factors Statement (continued) Total Ending Ending Total Realized Principal Certificate Certificate Principal Class Loss (3) Reduction Balance Percentage Distribution A1 0.00000000 5072.~~37441712~~83380904 ~~754~~620.~~54653865~~84009517 0.~~75454654~~62084010 5072.~~37441712~~83380904 A2 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 A3 0.00000000 4658.~~17858764~~01564952 ~~767~~648.~~94295632~~50352949 0.~~76794296~~64850353 4658.~~17858764~~01564952 A4 0.00000000 ~~110~~148.~~64589809~~75976872 ~~470~~201.~~24495368~~95345755 0.~~47024495~~20195346 ~~110~~148.~~64589809~~75976872 A5 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 A6 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 M1 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 M2 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 M3 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 M4 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 M5 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 M6 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 M7 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 CE 0.00000000 0.00000000 1,000.01793586 1.00001794 0.00000000 R 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 R-X 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 P 0.00000000 0.00000000 1,000.00000000 1.00000000 0.00000000 (3) Amount Does Not Include Excess Special Hazard, Bankruptcy, or Fraud Losses Unless Otherwise Disclosed. Please Refer to the Prospectus Supplement for a Full Description.

Interest Distribution Statement Beginning Payment of Original Current Certificate/ Current Unpaid Current Face Certificate Notional Accrued Interest Interest Class Amount Rate Balance Interest Shortfall Shortfall A1 253,534,000.00 12.~~83500~~15250% ~~204~~175,~~074~~869,~~829~~919.6063 ~~343~~336,~~270~~497.8778 0.00 0.00 A2 28,170,000.00 12.~~99500~~31250% 28,170,000.00 5157,~~515~~905.8900 0.00 0.00 A3 151,682,000.00 12.~~84500~~16250% ~~123~~107,~~487~~166,~~584~~242.0311 ~~208~~205,~~848~~997.3833 0.00 0.00 A4 80,421,000.00 12.~~71500~~03250% 4628,~~715~~204,~~823~~708.1937 7350,~~441~~956.1751 0.00 0.00 A5 79,850,000.00 12.~~83500~~15250% 79,850,000.00 ~~134~~152,~~314~~779.3567 0.00 0.00 A6 17,315,000.00 2.~~01500~~33250% 17,315,000.00 3135,~~982~~899.2577 0.00 0.00 M1 52,644,000.00 2.~~13500~~45250% 52,644,000.00 ~~103~~114,~~028~~763.7092 0.00 0.00 M2 42,653,000.00 23.~~76500~~08250% 42,653,000.00 ~~108~~116,~~107~~869.5822 0.00 0.00 M3 13,065,000.00 23.~~96500~~28250% 13,065,000.00 3538,~~509~~120.5877 0.00 0.00 M4 11,912,000.00 3.~~41500~~73250% 11,912,000.00 3739,~~289~~521.5237 0.00 0.00 M5 9,222,000.00 3.~~56500~~88250% 9,222,000.00 3031,~~136~~826.7315 0.00 0.00 M6 11,528,000.00 45.~~86500~~18250% 11,528,000.00 5153,~~410~~105.0865 0.00 0.00 M7 8,454,000.00 6.00000% 8,454,000.00 42,270.00 0.00 0.00 CE 8,069,309.07 0.00000% 8,069,453.80 0.00 0.00 0.00 R 0.00 0.00000% 0.00 0.00 0.00 0.00 R-X 0.00 0.00000% 0.00 0.00 0.00 0.00 P 100.00 0.00000% 100.00 0.00 0.00 0.00 Totals 768,519,409.07 1,~~251~~276,~~125~~513.1014 0.00 0.00

Interest Distribution Statement (continued) Remaining Ending Non-Supported Total Unpaid Certificate/ Interest Realized Interest Interest Notional Class Shortfall Losses (4) Distribution Shortfall Balance A1 0.00 0.00 ~~343~~336,~~270~~497.8778 0.00 ~~191~~157,~~303~~404,~~202~~072.1369 A2 0.00 0.00 5157,~~515~~905.8900 0.00 28,170,000.00 A3 0.00 0.00 ~~208~~205,~~848~~997.3833 0.00 ~~116~~98,~~483~~366,~~123~~312.5036 A4 0.00 0.00 7350,~~441~~956.1751 0.00 3716,~~817~~241,~~569~~299.4201 A5 0.00 0.00 ~~134~~152,~~314~~779.3567 0.00 79,850,000.00 A6 0.00 0.00 3135,~~982~~899.2577 0.00 17,315,000.00 M1 0.00 0.00 ~~103~~114,~~028~~763.7092 0.00 52,644,000.00 M2 0.00 0.00 ~~108~~116,~~107~~869.5822 0.00 42,653,000.00 M3 0.00 0.00 3538,~~509~~120.5877 0.00 13,065,000.00 M4 0.00 0.00 3739,~~289~~521.5237 0.00 11,912,000.00 M5 0.00 0.00 3031,~~136~~826.7315 0.00 9,222,000.00 M6 0.00 0.00 5153,~~410~~105.0865 0.00 11,528,000.00 M7 0.00 0.00 42,270.00 0.00 8,454,000.00 CE 0.00 0.00 2,~~532~~139,~~831~~859.9364 0.00 8,069,453.80 R 0.00 0.00 0.00 0.00 0.00 R-X 0.00 0.00 0.00 0.00 0.00 P 0.00 0.00 ~~612~~929,~~084~~627.4311 0.00 100.00 Totals 0.00 0.00 4,~~396~~345,~~041~~999.4689 0.00 (4) Amount Does Not Include Excess Special Hazard, Bankruptcy, or Fraud Losses Unless Otherwise Disclosed. Please Refer to the Prospectus Supplement for a Full Description.

Interest Distribution Factors Statement Beginning Payment of Original Current Certificate/ Current Unpaid Current Face Certificate Notional Accrued Interest Interest Class (5) Amount Rate Balance Interest Shortfall Shortfall A1 253,534,000.00 12.~~83500~~15250% ~~804~~693.~~92095577~~67390421 1.~~35394413~~32722941 0.00000000 0.00000000 A2 28,170,000.00 12.~~99500~~31250% 1000.00000000 12.~~82875009~~05555556 0.00000000 0.00000000 A3 151,682,000.00 12.~~84500~~16250% ~~814~~706.~~12154395~~51917901 1.~~37688308~~35808685 0.00000000 0.00000000 A4 80,421,000.00 12.~~71500~~03250% ~~580~~350.~~89085177~~71322627 0.~~91320886~~63362194 0.00000000 0.00000000 A5 79,850,000.00 12.~~83500~~15250% 1000.00000000 1.~~68208328~~91333338 0.00000000 0.00000000 A6 17,315,000.00 2.~~01500~~33250% 1000.00000000 12.~~84708345~~07333353 0.00000000 0.00000000 M1 52,644,000.00 2.~~13500~~45250% 1000.00000000 12.~~95708343~~18000000 0.00000000 0.00000000 M2 42,653,000.00 23.~~76500~~08250% 1000.00000000 2.~~53458326~~74000000 0.00000000 0.00000000 M3 13,065,000.00 23.~~96500~~28250% 1000.00000000 2.~~71791657~~91777803 0.00000000 0.00000000 M4 11,912,000.00 3.~~41500~~73250% 1000.00000000 3.~~13041639~~31777787 0.00000000 0.00000000 M5 9,222,000.00 3.~~56500~~88250% 1000.00000000 3.~~26791694~~45111147 0.00000000 0.00000000 M6 11,528,000.00 45.~~86500~~18250% 1000.00000000 4.~~45958362~~60666638 0.00000000 0.00000000 M7 8,454,000.00 6.00000% 1000.00000000 5.00000000 0.00000000 0.00000000 CE 8,069,309.07 0.00000% 1000.01793586 0.00000000 0.00000000 0.00000000 R 0.00 0.00000% 0.00000000 0.00000000 0.00000000 0.00000000 R-X 0.00 0.00000% 0.00000000 0.00000000 0.00000000 0.00000000 P 100.00 0.00000% 1000.00000000 0.00000000 0.00000000 0.00000000 (5) All Classes are per $1000 denomination.

Interest Distribution Factors Statement (continued) Remaining Ending Non-Supported Total Unpaid Certificate/ Interest Realized Interest Interest Notional Class Shortfall Losses (6) Distribution Shortfall Balance A1 0.00000000 0.00000000 1.~~35394413~~32722941 0.00000000 ~~754~~620.~~54653865~~84009517 A2 0.00000000 0.00000000 12.~~82875009~~05555556 0.00000000 1000.00000000 A3 0.00000000 0.00000000 1.~~37688308~~35808685 0.00000000 ~~767~~648.~~94295632~~50352949 A4 0.00000000 0.00000000 0.~~91320886~~63362194 0.00000000 ~~470~~201.~~24495368~~95345755 A5 0.00000000 0.00000000 1.~~68208328~~91333338 0.00000000 1000.00000000 A6 0.00000000 0.00000000 12.~~84708345~~07333353 0.00000000 1000.00000000 M1 0.00000000 0.00000000 12.~~95708343~~18000000 0.00000000 1000.00000000 M2 0.00000000 0.00000000 2.~~53458326~~74000000 0.00000000 1000.00000000 M3 0.00000000 0.00000000 2.~~71791657~~91777803 0.00000000 1000.00000000 M4 0.00000000 0.00000000 3.~~13041639~~31777787 0.00000000 1000.00000000 M5 0.00000000 0.00000000 3.~~26791694~~45111147 0.00000000 1000.00000000 M6 0.00000000 0.00000000 4.~~45958362~~60666638 0.00000000 1000.00000000 M7 0.00000000 0.00000000 5.00000000 0.00000000 1000.00000000 CE 0.00000000 0.00000000 ~~313~~265.~~88460995~~18498938 0.00000000 1000.01793586 R 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 R-X 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 P 0.00000000 0.00000000 ~~6120844~~9296271.~~30000000~~10000000 0.00000000 1000.00000000 (6) Amount Does Not Include Excess Special Hazard, Bankruptcy,or Fraud Losses Unless Otherwise Disclosed. Please Refer to the Prospectus Supplement for a Full Description.

CERTIFICATEHOLDER ACCOUNT STATEMENT CERTIFICATE ACCOUNT Beginning Balance 0.00 Deposits Payments of Interest and Principal 3242,~~734~~895,~~853~~585.9375 Liquidations, Insurance Proceeds, Reserve Funds 0.00 Proceeds from Repurchased Loans 0.00 Other Amounts (Servicer Advances) 0.00 Realized Loss (Gains, Subsequent Expenses & Recoveries) 0.00 Prepayment Penalties ~~612~~929,~~084~~627.4311 Total Deposits 3343,~~346~~825,~~938~~212.3686 Withdrawals Reimbursement for Servicer Advances 0.00 Payment of Service Fee ~~276~~250,~~555~~026.1393 Payment of Interest and Principal 3343,~~070~~575,~~383~~185.2393 Total Withdrawals (Pool Distribution Amount) 3343,~~346~~825,~~938~~212.3686 Ending Balance 0.00

SERVICING FEES Gross Servicing Fee ~~273~~247,~~816~~551.9642 Administrator fee 2,~~738~~475.1751 Supported Prepayment/Curtailment Interest Shortfall 0.00 Net Servicing Fee ~~276~~250,~~555~~026.1393

LOAN STATUS STRATIFICATION/CREDIT ENHANCEMENT STATEMENT DELINQUENCY STATUS DELINQUENT BANKRUPTCY FORECLOSURE REO Total No of Loans No of Loans No of Loans No of Loans No of Loans Principal Balance Principal Balance Principal Balance Principal Balance Principal Balance 0-29 Days 1422 01 0 1423 12,~~203~~342,~~198~~268.7521 0113,833.0079 0.00 12,~~203~~456,~~198~~102.7500 30 Days 4866 10 1 0 5067 1011,~~254~~391,~~850~~375.5504 ~~66,770~~0.8500 ~~114~~202,~~009~~855.8573 0.00 1011,~~435~~594,~~631~~230.2577 60 Days 1719 03 06 0 1728 3,~~026~~797,~~983~~095.6068 0367,672.0056 0948,893.0040 0.00 35,~~026~~113,~~983~~661.6064 90 Days 7 6 320 312 480 ~~527~~18 631,~~144~~272.9317 ~~1,108,167~~0.4100 52,~~830~~101,~~728~~080.0867 ~~506,477~~0.5900 72,~~972~~732,~~518~~352.0184 120 Days 0 02 05 01 08 0.00 0539,989.0064 01,110,563.0078 055,415.0065 01,705,969.0007 150 Days 03 02 09 0 014 0298,478.0033 0239,458.0048 02,542,221.0020 0.00 03,080,158.0001 180+ Days 05 06 08 09 028 0322,165.0065 0495,377.0092 01,284,484.0019 01,223,238.0094 03,325,266.0070 Totals 7299 2135 3342 310 ~~129~~186 1316,~~808~~440,~~979~~386.0887 23,~~378~~984,~~137~~766.0181 58,~~944~~303,~~737~~932.9376 ~~506~~1,~~477~~278,654.59 2230,~~638~~007,~~331~~741.6103 No of Loans No of Loans No of Loans No of Loans No of Loans Principal Balance Principal Balance Principal Balance Principal Balance Principal Balance 0-29 Days 0.~~348866~~613839% 0.~~000000~~027902% 0.000000% 0.~~348866~~641741% 0.~~191290~~421734% 0.~~000000~~020496% 0.000000% 0.~~191290~~442231% 30 Days 1.~~196113~~841518% 0.~~024919~~000000% 0.~~024919~~027902% 0.000000% 1.~~245951~~869420% 12.~~630366~~051061% 0.~~010616~~000000% 0.~~018126~~036525% 0.000000% 12.~~659108~~087586% 60 Days 0.~~423623~~530134% 0.~~000000~~083705% 0.~~000000~~167411% 0.000000% 0.~~423623~~781250% 0.~~481245~~683682% 0.~~000000~~066201% 0.~~000000~~170852% 0.000000% 0.~~481245~~920735% 90 Days 0.~~174433~~167411% 0.~~149514~~000000% 0.~~797408~~334821% 0.~~074757~~000000% 10.~~196113~~502232% 0.~~083808~~113663% 0.~~176182~~000000% 0.~~926998~~378308% 0.~~080522~~000000% 10.~~267510~~491971% 120 Days 0.000000% 0.~~000000~~055804% 0.~~000000~~139509% 0.~~000000~~027902% 0.~~000000~~223214% 0.000000% 0.~~000000~~097227% 0.~~000000~~199961% 0.~~000000~~009978% 0.~~000000~~307166% 150 Days 0.~~000000~~083705% 0.~~000000~~055804% 0.~~000000~~251116% 0.000000% 0.~~000000~~390625% 0.~~000000~~053742% 0.~~000000~~043115% 0.~~000000~~457737% 0.000000% 0.~~000000~~554594% 180+ Days 0.~~000000~~139509% 0.~~000000~~167411% 0.~~000000~~223214% 0.~~000000~~251116% 0.~~000000~~781250% 0.~~000000~~058007% 0.~~000000~~089195% 0.~~000000~~231276% 0.~~000000~~220249% 0.~~000000~~598727% Totals 12.~~794169~~762277% 0.~~523299~~976563% 01.~~822327~~171875% 0.~~074757~~279018% 35.~~214553~~189732% 2.~~195419~~960155% 0.~~378088~~717473% 01.~~945123~~495155% 0.~~080522~~230227% 35.~~599153~~403010% (7) Delinquencies are stratified according to the information the Servicer has provided.

OTHER INFORMATION Current Period Class A Insufficient Funds 0.00 Principal Balance of Contaminated Properties 0.00 Periodic Advance ~~163~~194,~~758~~376.5202 Class A-6 157,547,309.07 20.50010803% 157,547,453.80 2528.~~06775669~~39233913% 23.~~755032~~120414% 0.000000% Class M-1 104,903,309.07 13.65005331% 104,903,453.80 1618.~~69144243~~90512581% 89.~~376314~~487213% 0.000000% Class M-2 62,250,309.07 8.10003083% 62,250,453.80 911.~~90482037~~21843579% 67.~~786622~~686690% 0.000000% Class M-3 49,185,309.07 6.40000870% 49,185,453.80 78.~~82601660~~86393306% 2.~~078804~~354503% 0.000000% Class M-4 37,273,309.07 4.85001532% 37,273,453.80 56.~~93066945~~71721767% 12.~~895347~~146715% 0.000000% Class CE 0.00 0.00000000% 0.00 0.00000000% 1.~~283950~~454233% 0.000000% Class R-I 0.00 0.00000000% 0.00 0.00000000% 0.000000% 0.000000% Please Refer to the Prospectus Supplement for a Full Description of Loss Exposure

COLLATERAL STATEMENT Collateral Description Mixed Fixed & Arm Weighted Average Gross Coupon 7.~~425740~~409308% Weighted Average Net Coupon 6.~~925740~~909308% Weighted Average Pass-Through Rate 6.~~920740~~904308% Weighted Average Maturity(Stepdown Calculation ) ~~331~~329 Beginning Scheduled Collateral Loan Count 43,~~176~~816 Number Of Loans Paid In Full ~~163~~232 Ending Scheduled Collateral Loan Count 43,~~013~~584 Beginning Scheduled Collateral Balance ~~657~~594,~~160~~123,~~790~~423.6290 Ending Scheduled Collateral Balance ~~628~~554,~~486~~894,~~448~~237.85 Ending Actual Collateral Balance at 31-~~Aug~~Oct-2004 ~~628~~555,~~990~~389,~~605~~341.7692 Monthly P &I Constant 4,~~589~~148,~~212~~883.1482 Special Servicing Fee 0.00 Prepayment Penalties ~~612~~929,~~084~~627.4311 Realized Loss Amount 0.00 Cumulative Realized Loss 0936.0010 Ending Scheduled Balance for Premium Loans ~~628~~554,~~486~~894,~~448~~237.85 Scheduled Principal ~~522~~480,~~624~~514.4550 Unscheduled Principal 2838,~~151~~748,~~717~~671.3255

Other Income -6(1,~~075~~969.5462)

Miscellaneous Reporting Net Monthly Excess Cashflow 2,~~532~~139,~~832~~859.0180 Extra Prinicpal Distribution Amount 0.00 OC Amount 8,069,453.80 OC Deficiency Amount 0.00 OC Release Amount 0.00 OC Target Amount 8,069,453.79 Stepdown 0.00 Trigger Event 0.00 Credit Enhancement Percentage 2326.~~973958~~517630422%

Group Level Collateral Statement Group Group 1 Group 2 Group 3 Collateral Description Fixed 15/30 & ARM Fixed 15/30 & ARM Fixed 15/30 & ARM Weighted Average Coupon Rate 8.~~233583~~163898 7.~~209235~~189048 8.~~220443~~183719 Weighted Average Net Rate 7.~~733583~~663898 6.~~709235~~689048 7.~~720443~~683719 Weighted Average Maturity ~~288~~286 ~~350~~348 ~~290~~288 Beginning Loan Count ~~981~~911 1,~~322~~208 ~~512~~470 Loans Paid In Full 3649 5071 1626 Ending Loan Count ~~945~~862 1,~~272~~137 ~~496~~444 Beginning Scheduled Balance 8075,~~693~~462,~~597~~792.9667 ~~224~~201,~~039~~066,~~975~~291.8761 4340,~~672~~484,~~139~~768.8058 Ending scheduled Balance 7771,~~921~~388,~~110~~220.7772 ~~214~~186,~~040~~675,~~835~~016.5962 4238,~~543~~676,~~981~~175.6982 Record Date 0810/31/2004 0810/31/2004 0810/31/2004 Principal And Interest Constant ~~625~~582,~~176~~700.8510 1,~~524~~366,~~202~~568.4033 ~~337~~313,~~944~~110.5903 Scheduled Principal 7169,~~512~~308.3301 ~~178~~162,~~238~~005.4060 3837,~~774~~013.3039 Unscheduled Principal 24,~~700~~005,~~974~~263.8694 914,~~820~~229,~~901~~269.8839 1,~~089~~771,~~383~~579.8137 Scheduled Interest ~~553~~513,~~664~~392.5209 1,~~345~~204,~~964~~562.0073 ~~299~~276,~~170~~096.2964 Servicing Fees 3331,~~622~~442.3383 9383,~~349~~777.9862 1816,~~196~~868.7265 Master Servicing Fees 0.00 0.00 0.00 Trustee Fee 0.00 0.00 0.00 FRY Amount 0.00 0.00 0.00 Special Hazard Fee 0.00 0.00 0.00 Other Fee ~~336~~314.2142 ~~933~~837.5176 ~~181~~168.9669 Pool Insurance Fee 0.00 0.00 0.00 Spread Fee 1 0.00 0.00 0.00 Spread Fee 2 0.00 0.00 0.00 Spread Fee 3 0.00 0.00 0.00 Net Interest ~~519~~481,~~705~~634.9884 1,~~251~~119,~~680~~947.5135 ~~280~~259,~~791~~059.6130 Realized Loss Amount 0.00 0.00 0.00 Cumulative Realized Loss 0.00 0.00 0.00 Percentage of Cumulative Losses 0.0000 0.0000 0.0000 Prepayment Penalties 0.00 0.00 0.00 Special Servicing Fee 0.00 0.00 0.00 Pass-Through Rate 7.~~728583~~658898 6.~~704235~~684048 7.~~715443~~678719

Group Level Collateral Statement Group Group 4 Group 5 Group 6 Collateral Description Fixed 15/30 & ARM Fixed 15/30 & ARM Fixed 15/30 & ARM Weighted Average Coupon Rate 7.~~163610~~178803 8.~~630866~~559798 6.~~835450~~806635 Weighted Average Net Rate 6.~~663610~~678804 8.~~130866~~059798 6.~~335450~~306635 Weighted Average Maturity ~~350~~348 ~~249~~247 ~~350~~348 Beginning Loan Count ~~684~~619 ~~352~~317 ~~325~~291 Loans Paid In Full 2933 1632 1621 Ending Loan Count ~~655~~586 ~~336~~285 ~~309~~270 Beginning Scheduled Balance ~~118~~105,~~839~~706,~~835~~118.5768 5147,~~168~~717,~~247~~896.5785 ~~138~~123,~~746~~685,~~993~~555.8551 Ending scheduled Balance ~~112~~98,~~963~~714,~~533~~781.1569 4944,~~699~~387,~~454~~743.3207 ~~131~~115,~~317~~052,~~533~~299.3393 Record Date 0810/31/2004 0810/31/2004 0810/31/2004 Principal And Interest Constant ~~805~~718,~~190~~083.0775 ~~403~~374,~~573~~676.5886 ~~893~~793,~~124~~744.6575 Scheduled Principal 9585,~~754~~714.8621 3534,~~551~~297.6922 ~~102~~92,~~792~~176.8707 Unscheduled Principal 56,~~780~~905,~~547~~622.5678 13,~~433~~295,~~241~~856.56 78,~~326~~541,~~667~~079.6551 Scheduled Interest ~~709~~632,~~435~~369.2154 ~~368~~340,~~021~~379.8964 ~~790~~701,~~331~~568.7868 Servicing Fees 4944,~~516~~044.60 21 19,~~320~~882.0945 5751,~~811~~535.2466 Master Servicing Fees 0.00 0.00 0.00 Trustee Fee 0.00 0.00 0.00 FRY Amount 0.00 0.00 0.00 Special Hazard Fee 0.00 0.00 0.00 Other Fee ~~495~~440.1744 ~~213~~198.2183 ~~578~~515.1137 Pool Insurance Fee 0.00 0.00 0.00 Spread Fee 1 0.00 0.00 0.00 Spread Fee 2 0.00 0.00 0.00 Spread Fee 3 0.00 0.00 0.00 Net Interest ~~659~~587,~~423~~884.4489 ~~346~~320,~~488~~298.5936 ~~731~~649,~~942~~517.4365 Realized Loss Amount 0.00 0.00 0.00 Cumulative Realized Loss 0.00 0.00 0936.0010 Percentage of Cumulative Losses 0.0000 0.0000 0.~~0000~~0006 Prepayment Penalties 0.00 0.00 0.00 Special Servicing Fee 0.00 0.00 0.00 Pass-Through Rate 6.~~658610~~673803 8.~~125866~~054798 6.~~330450~~301635

Group Level Collateral Statement Group Total Collateral Description Mixed Fixed & Arm Weighted Average Coupon Rate 7.~~425740~~409308 Weighted Average Net Rate 6.~~925740~~909308 Weighted Average Maturity ~~331~~329.00 Record Date 0810/31/2004 Principal And Interest Constant 4,~~589~~148,~~212~~883.1482 Beginning Loan Count 43,~~176~~816 Loans Paid In Full ~~163~~232 Ending Loan Count 43,~~013~~584 Beginning Scheduled Balance ~~657~~594,~~160~~123,~~790~~423.6290 Ending Scheduled Balance ~~628~~554,~~486~~894,~~448~~237.85 Scheduled Principal ~~522~~480,~~624~~514.4550 Unscheduled Principal 2838,~~151~~748,~~717~~671.3255 Scheduled Interest 43,~~066~~668,~~587~~369.6932 Servicing Fee ~~273~~247,~~816~~551.9642 Master Servicing Fee 0.00 Trustee Fee 0.00 Fry Amount 0.00 Special Hazard Fee 0.00 Other Fee 2,~~738~~475.1751 Pool Insurance Fee 0.00 Spread 1 0.00 Spread 2 0.00 Spread 3 0.00 Net Interest 3,~~790~~418,~~032~~342.5639 Realized Loss Amount 0.00 Cumulative Realized Loss 0936.0010 Percentage of Cumulative Losses 0.~~0000~~0001 Prepayment Penalties 0.00 Special Servicing Fee 0.00 Pass-Through Rate 6.~~920740~~904308

Filing Compare · MORTGAGE ASSET SEC TRANS INC MASTR AS BK SEC TR 2004 WMC1