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): ~~August~~October 25, 2005 (Date of earliest event reported) Indymac MBS Inc (as Depositor under the Pooling and Servicing Agreement, dated as March 1, 2005, providing for the issuance of Residential Asset Securitization Trust Series 2005-A4 Mortgage Pass-Through Certificates, Series 2005-D) (Exact name of registrant as specified in charter) DELAWARE (State or Other Jurisdiction of Incorporation) 333-119384-18 95-4791925 (Commission File Number) (I.R.S. Employer Identification No.) 155 NORTH LAKE AVENUE PASADENA, CALIFORNIA 91101 (Address of principal executive offices) (Zip Code) Registrant's Telephone Number, Including Area Code: (800) 669-2300 (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(b) under the Exchange Act (17 CFR 240.14a-12(b)) [ ] 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 Attached hereto is a copy of the Monthly Remittance Statements to the Certificateholders which was derived from the monthly information submitted by the Master Servicer of the Trust to the Trustee. Item 9.01 Financial Statements and Exhibits (c) Exhibits: Exhibit No. Description 99.1 Monthly Remittance Statement to the Certificateholders dated as of ~~August~~October 25, 2005. Signatures 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. Deutsche Bank National Trust Company, in its capacity as Trustee under the Pooling and Servicing Agreement on behalf of Indymac MBS Inc, Registrant Date: ~~Aug~~Oct 2628, 2005 By: /s/ Katherine M. Wannenmacher Katherine M. Wannenmacher Vice President EXHIBIT INDEX DOCUMENT 99.1 Monthly Remittance Statement to the Certificateholders dated as of ~~August~~October 25, 2005.

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

External Parties

Table of Contents

Page

Seller

1. Certificate Payment Report

IndyMac Bank

2. Collection Account Report

3. Credit Enhancement Report

4. Collateral Report

Certificate Insurer(s)

5. Delinquency Report

6. REO Report

7. Foreclosure Report

8. Prepayment Report

9. Prepayment Detail Report

10. Realized Loss Report

11. Realized Loss Detail Report

Servicer(s)

12. Triggers and Adj. Cert. Report

IndyMac Bank

13. Other Related Information

Underwriter(s)

UBS Investment Bank

Total Number of Pages

Dates

Contacts

Cut-Off Date:

March 01, 2005

Jennifer Hermansader

Close Date:

March 30, 2005

Administrator

First Distribution Date:

April 25, 2005

(714) 247-6258

Jennifer.Vandyne@db.com

Address:

1761 East St. Andrew Place, Santa Ana, CA 92705

Distribution Date:

~~August~~October 25, 2005

Factor Information:

(800) 735-7777

Record Date:

~~July~~September 2930, 2005

Main Phone Number:

(714) 247-6000

August 24, 2005

October 24, 2005

https://www.tss.db.com/invr

Page 1 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Certificate Payment Report

Current Period Distribution - MASTER-REMIC

Prior

Current

Class

Original

Principal

Total

Realized

Deferred

Principal

Class

Type

Cur

Face Value

Balance

Interest

Principal

Distribution

Loss

Interest

Balance

(1)

(2)

(3)

(4)=(2)+(3)

(5)

(6)

(7)=(1)-(3)-(5)+(6)

A-1

191,578,000.00

~~184~~174,~~335~~883,~~177~~160.8104

~~600~~623,~~625~~749.4594

43,~~969~~262,~~610~~312.5414

53,~~570~~886,~~235~~062.9908

0.00

~~179~~171,~~365~~620,~~567~~847.2790

A-2

SR/NTL

0.00

~~244~~177,~~244~~797.1188

0.00

~~244~~177,~~244~~797.1188

0.00

A-X

SR/NTL

0.00

3532,~~281~~690.9984

0.00

3532,~~281~~690.9984

0.00

A-R

SR/RES

100.00

0.00

B-1

SUB

4,040,000.00

4,~~025~~018,~~736~~565.1966

18,~~451~~418.2943

3,~~576~~641.4592

22,~~027~~060.7435

0.00

4,~~022~~014,~~159~~923.74

B-2

SUB

1,819,000.00

1,~~812~~809,~~577~~349.7624

8,~~307~~292.6585

1,~~610~~639.2977

9,~~917~~932.9462

0.00

1,~~810~~807,~~967~~709.47

B-3

SUB

1,010,000.00

1,~~006~~004,~~434~~641.0441

4,~~612~~604.8261

~~894~~910.1148

5,~~506~~515.9309

0.00

1,~~005~~003,~~539~~730.93

B-4

SUB/NOF

1,010,000.00

1,~~006~~004,~~434~~641.0441

4,~~612~~604.8261

~~894~~910.1148

5,~~506~~515.9309

0.00

1,~~005~~003,~~539~~730.93

B-5

SUB/NOF

707,000.00

~~704~~703,~~503~~248.8399

3,~~228~~223.9822

~~625~~637.8834

3,~~854~~860.8656

0.00

~~703~~702,~~877~~611.9565

B-6

SUB/NOF

505,304.00

~~503~~502,~~519~~623.9813

2,~~307~~303.8069

~~447~~455.3250

2,~~755~~759.1219

0.00

~~503~~502,~~072~~167.6663

SR/NOF

100.00

56,~~941~~740.5030

0.00

56,~~941~~740.5030

0.00

100.00

1,344,824.00

1,~~303~~267,~~402~~905.5925

0.00

1516,~~790~~279.9433

0.00

1,~~287~~251,~~611~~625.6592

Total

202,014,328.00

185,194,~~697,886~~235.2413

~~927~~882,~~614~~426.4137

43,~~993~~286,~~449~~786.6496

54,~~921~~169,~~064~~213.0533

0.00

~~189~~181,~~704~~907,~~436~~448.6017

Interest Accrual Detail Current Period Factor Information per $1,000 of Original Face-

Orig. Principal

Prior

Current

Period

(with Notional)

Principal

Total

Principal

Class

Starting

Ending

Method

Cusip

Balance

Interest

Principal

Distribution

Balance

(1)

(2)

(3)

(4)=(2)+(3)

(5)

A-1

0709/25/05

0810/24/05

F-30/360

45660LHD4

191,578,000.00

~~962~~912.~~193873~~856174

3.~~135148~~255854

2517.~~940403~~028637

2920.~~075551~~284490

~~936~~895.~~253470~~827537

A-2

0709/25/05

0810/24/05

F-30/360

45660LHE2

191,578,000.00

~~962~~912.~~193873~~856174

10.~~274907~~928070

0.000000

10.~~274907~~928070

~~936~~895.~~253470~~827537

A-X

0709/01/05

0709/30/05

F-30/360

45660LHG7

135,826,941.98

~~960~~907.~~606560~~201863

0.~~259757~~240680

0.000000

0.~~259757~~240680

~~929~~892.~~615755~~186013

A-R

0709/01/05

0709/30/05

F-30/360

45660LHH5

100.00

0.000000

B-1

0709/01/05

0709/30/05

F-30/360

45660LHJ1

4,040,000.00

~~996~~994.~~469354~~694470

4.~~567151~~559017

0.~~885260~~901465

5.~~452411~~460483

~~995~~993.~~584094~~793005

B-2

0709/01/05

0709/30/05

F-30/360

45660LHK8

1,819,000.00

~~996~~994.~~469357~~694469

4.~~567152~~559016

0.~~885261~~901468

5.~~452413~~460484

~~995~~993.~~584096~~793002

B-3

0709/01/05

0709/30/05

F-30/360

45660LHL6

1,010,000.00

~~996~~994.~~469347~~694465

4.~~567149~~559020

0.~~885257~~901465

5.~~452406~~460485

~~995~~993.~~584089~~793000

B-4

0709/01/05

0709/30/05

F-30/360

45660LHN2

1,010,000.00

~~996~~994.~~469347~~694465

4.~~567149~~559020

0.~~885257~~901465

5.~~452406~~460485

~~995~~993.~~584089~~793000

B-5

0709/01/05

0709/30/05

F-30/360

45660LHP7

707,000.00

~~996~~994.~~469349~~694470

4.~~567157~~559010

0.~~885262~~901471

5.~~452419~~460481

~~995~~993.~~584088~~792999

B-6

0709/01/05

0709/30/05

F-30/360

45660LHQ5

505,304.00

~~996~~994.~~469412~~694540

4.~~567152~~559018

0.~~885249~~901438

5.~~452401~~460455

~~995~~993.~~584163~~793103

0709/01/05

0709/30/05

F-30/360

45660LHM4

100.00

1,000.000000

5967,~~415~~403.000000

0.000000

5967,~~415~~403.000000

1,000.000000

0709/01/05

0709/30/05

F-30/360

45660LHF9

1,344,824.00

~~969~~942.~~199382~~803854

0.000000

1112.~~742012~~105175

~~957~~930.~~457370~~698679

Page 2 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Distribution to Date - MASTER-REMIC

Current

Original

Unscheduled

Scheduled

Total

Realized

Deferred

Principal

Class

Face Value

Interest

Principal

Distribution

Loss

Interest

Balance

(1)

(2)

(3)

(4)

(5)=(3)+(4)

(6)=(2)+(5)

(7)

(8)

(9)=(1)-(5)-(7)+(8)

A-1

191,578,000.00

24,~~817~~053,~~899~~173.2567

1118,~~380~~805,~~012~~964.4819

~~832~~1,~~420~~151,187.2591

1219,~~212~~957,~~432~~152.7310

1524,~~030~~010,~~331~~325.9877

0.00

~~179~~171,~~365~~620,~~567~~847.2790

A-2

0.00

1,~~494~~882,~~604~~970.6624

0.00

1,~~494~~882,~~604~~970.6624

0.00

A-X

0.00

~~180~~246,~~529~~844.1639

0.00

~~180~~246,~~529~~844.1639

0.00

A-R

100.00

0.5051

0.00

100.00

100.5051

0.00

B-1

4,040,000.00

92129,~~420~~273.0639

0.00

1725,~~840~~076.26

~~110~~154,~~260~~349.3265

0.00

4,~~022~~014,~~159~~923.74

B-2

1,819,000.00

4158,~~611~~205.9002

0.00

811,~~032~~290.53

4969,~~644~~495.4355

0.00

1,~~810~~807,~~967~~709.47

B-3

1,010,000.00

2332,~~105~~318.0134

0.00

46,~~460~~269.07

2738,~~565~~587.0841

0.00

1,~~005~~003,~~539~~730.93

B-4

1,010,000.00

2332,~~105~~318.0134

0.00

46,~~460~~269.07

2738,~~565~~587.0841

0.00

1,~~005~~003,~~539~~730.93

B-5

707,000.00

1622,~~173~~622.5184

0.00

34,~~122~~388.0535

1927,~~295~~011.5619

0.00

~~703~~702,~~877~~611.9565

B-6

505,304.00

1116,~~559~~168.4791

0.00

23,~~231~~136.3437

1319,~~790~~305.8128

0.00

~~503~~502,~~072~~167.6663

100.00

1324,~~676~~619.6737

0.00

1324,~~676~~619.6737

0.00

100.00

1,344,824.00

0.00

5083,~~110~~312.8593

79,~~101~~885.5015

5793,~~212~~198.3508

0.00

1,~~287~~251,~~611~~625.6592

Total

202,014,328.00

46,~~714~~498,~~685~~515.2002

1118,~~430~~889,~~123~~277.3312

~~879~~1,~~768~~217,602.0771

1220,~~309~~106,~~891~~879.4083

1726,~~024~~605,~~576~~394.6085

0.00

~~189~~181,~~704~~907,~~436~~448.6017

Interest Detail - MASTER-REMIC

Pass

Prior Principal

Non-

Prior

Unscheduled

Paid or

Current

Through

(with Notional)

Accrued

Supported

Unpaid

Interest

Optimal

Deferred

Unpaid

Class

Rate

Balance

Interest

Interest SF

Interest

Adjustment

Interest

(1)

(2)

(3)

(4)

(5)=(1)-(2)+(3)+(4)

(6)

(7)=(5)-(6)

A-1

34.~~91000~~28000%

~~184~~174,~~335~~883,~~177~~160.8104

~~600~~623,~~625~~749.4594

0.00

~~600~~623,~~625~~749.4594

0.00

A-2

1.~~59000~~22000%

~~184~~174,~~335~~883,~~177~~160.8104

~~244~~177,~~244~~797.1188

0.00

~~244~~177,~~244~~797.1188

0.00

A-X

0.~~32449~~31836%

~~130~~123,~~476~~222,~~251~~454.5087

3532,~~281~~690.9984

0.00

3532,~~281~~690.9984

0.00

A-R

0.00000%

0.00

B-1

5.50000%

4,~~025~~018,~~736~~565.1966

18,~~451~~418.2943

0.00

18,~~451~~418.2943

0.00

B-2

5.50000%

1,~~812~~809,~~577~~349.7624

8,~~307~~292.6585

0.00

8,~~307~~292.6585

0.00

B-3

5.50000%

1,~~006~~004,~~434~~641.0441

4,~~612~~604.8261

0.00

4,~~612~~604.8261

0.00

B-4

5.50000%

1,~~006~~004,~~434~~641.0441

4,~~612~~604.8261

0.00

4,~~612~~604.8261

0.00

B-5

5.50000%

~~704~~703,~~503~~248.8399

3,~~228~~223.9822

0.00

3,~~228~~223.9822

0.00

B-6

5.50000%

~~503~~502,~~519~~623.9813

2,~~307~~303.8069

0.00

2,~~307~~303.8069

0.00

7180,~~298~~883.~~00000~~60000%

100.00

0.00

56,~~941~~740.5030

0.00

0.00000%

1,~~303~~267,~~402~~905.5925

0.00

Total

~~509~~483,~~509~~299,~~315~~850.5504

~~921~~875,~~672~~686.9107

0.00

~~921~~875,~~672~~686.9107

~~927~~882,~~614~~426.4137

0.00

Page 3 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Collection Account Report

SUMMARY

Total

Principal Collections

43,~~993~~286,~~449~~786.6496

Principal Withrawals

0.00

Principal Other Accounts

0.00

TOTAL NET PRINCIPAL

43,~~993~~286,~~449~~786.6496

Interest Collections

~~934~~887,~~683~~980.7200

Interest Withdrawals

-0.00

Interest Other Accounts

56,~~941~~740.5030

Interest Fees

-1312,~~010~~293.8193

TOTAL NET INTEREST

~~927~~882,~~614~~426.4137

TOTAL AVAILABLE FUNDS FOR DISTRIBUTION

54,~~921~~169,~~064~~213.0533

PRINCIPAL - COLLECTIONS

Total

Scheduled Principal Received

~~173~~168,~~219~~074.4889

Curtailments

~~375~~25,~~241~~610.0349

Prepayments In Full

43,~~444~~093,~~989~~101.1358

Repurchased/Substitutions

0.00

Liquidations

0.00

Insurance Principal

0.00

Other Additional Principal

0.00

Delinquent Principal

-~~134~~129,~~945~~688.26

Realized Losses

-0.00

Advanced Principal

~~134~~129,~~945~~688.26

TOTAL PRINCIPAL COLLECTED

43,~~993~~286,~~449~~786.6496

PRINCIPAL - WITHDRAWALS

SPACE INTENTIONALLY LEFT BLANK

PRINCIPAL - OTHER ACCOUNTS

Total

TOTAL PRINCIPAL OTHER ACCOUNTS

0.00

Page 4 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

INTEREST - COLLECTIONS

Total

Scheduled Interest

~~971~~923,~~680~~210.0051

Repurchased/Substitution Interest

0.00

Liquidation Interest

0.00

Insurance Interest

0.00

Other Additional Interest

0.00

Prepayment Interest Shortfalls

-32,~~054~~224.8228

Delinquent Interest

-~~745~~709,~~258~~784.5180

Compensating Interest

32,~~054~~224.8228

Civil Relief Act Shortfalls

-0.00

Interest Advanced

~~708~~674,~~262~~554.2229

TOTAL INTEREST COLLECTED

~~934~~887,~~683~~980.7200

INTEREST - WITHDRAWALS

Total

TOTAL INTEREST WITHDRAWALS

0.00

INTEREST - OTHER ACCOUNTS

Total

Prepayment Charges

56,~~941~~740.5030

Payments Received from CAP Contract

0.00

TOTAL INTEREST OTHER ACCOUNTS

56,~~941~~740.5030

INTEREST - FEES

Total

Current Servicing Fees

1110,~~155~~518.8357

Trustee Fees

1,~~622~~543.4828

TOTAL INTEREST FEES

1312,~~010~~293.8193

Page 5 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Credit Enhancement Report

ACCOUNTS

SPACE INTENTIONALLY LEFT BLANK

INSURANCE

Total

PMI

232.5008

STRUCTURAL FEATURES

SPACE INTENTIONALLY LEFT BLANK

Page 6 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Collateral Report

COLLATERAL

Total

Loan Count:

Original

952

Prior

~~924~~886

Prefunding

Scheduled Paid Offs

-0

Full Voluntary Prepayments

-2011

Repurchases

-0

Liquidations

-0

Current

~~904~~875

Principal Balance:

Original

202,014,229.00

Prior

185,194,~~697,787~~136.2211

Prefunding

0.00

Scheduled Principal

-~~173~~168,~~219~~074.4889

Partial Prepayments

-~~375~~25,~~241~~610.0349

Full Voluntary Prepayments

-43,~~444~~093,~~989~~101.1358

Repurchases

-0.00

Liquidations

-0.00

Current

~~189~~181,~~704~~907,~~337~~349.5815

PREFUNDING

SPACE INTENTIONALLY LEFT BLANK

Page 7 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

CHARACTERISTICS

Total

Weighted Average Coupon Original

5.99027%

Weighted Average Coupon Prior

5.~~98991~~98329%

Weighted Average Coupon Current

5.~~98885~~98211%

Weighted Average Months to Maturity Original

356

Weighted Average Months to Maturity Prior

~~353~~351

Weighted Average Months to Maturity Current

~~352~~350

Weighted Avg Remaining Amortization Term Original

356

Weighted Avg Remaining Amortization Term Prior

~~353~~351

Weighted Avg Remaining Amortization Term Current

~~352~~350

Weighted Average Seasoning Original

2.57

Weighted Average Seasoning Prior

57.5856

Weighted Average Seasoning Current

68.56

Page 8 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

ARM CHARACTERISTICS

Total

Weighted Average Margin Original

0.00000%

Weighted Average Margin Prior

0.00000%

Weighted Average Margin Current

0.00000%

Weighted Average Max Rate Original

0.00000%

Weighted Average Max Rate Prior

0.00000%

Weighted Average Max Rate Current

0.00000%

Weighted Average Min Rate Original

0.00000%

Weighted Average Min Rate Prior

0.00000%

Weighted Average Min Rate Current

0.00000%

Weighted Average Cap Up Original

0.00000%

Weighted Average Cap Up Prior

0.00000%

Weighted Average Cap Up Current

0.00000%

Weighted Average Cap Down Original

0.00000%

Weighted Average Cap Down Prior

0.00000%

Weighted Average Cap Down Current

0.00000%

SERVICING FEES & ADVANCES

Total

Current Servicing Fees

1110,~~155~~518.8357

Delinquent Servicing Fees

3635,~~996~~230.2951

TOTAL SERVICING FEES

4845,~~152~~749.1208

Total Servicing Fees

4845,~~152~~749.1208

Compensating Interest

-32,~~054~~224.8228

Delinquent Servicing Fees

-3635,~~996~~230.2951

COLLECTED SERVICING FEES

8,~~101~~294.0130

Total Advaced Interest

~~708~~674,~~262~~554.2229

Total Advaced Principal

~~134~~129,~~945~~688.26

Aggregate Advances with respect to this Distribution

~~843~~804,~~207~~242.4855

ADDITIONAL COLLATERAL INFORMATION

Total

Prepayment Interest Shortfall (PPIS)

32,~~054~~224.8228

Compensating Interest

-32,~~054~~224.8228

Net Prepayment Interest Shortfall (PPIS)

0.00

Weighted Average Net Mortgage Rate

5.~~680637~~674171%

LIBOR for the Current Period

3.~~460000~~830000%

LIBOR for the Next Period

0.000000%

Page 9 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Delinquency Report

TOTAL

< 1 PAYMENT

1 PAYMENT

2 PAYMENTS

3+ PAYMENTS

TOTAL

DELINQUENT

Balance

21,~~809~~279,~~272~~469.0579

~~404~~130,~~141~~701.4703

~~159~~281,~~355~~782.6838

31,~~372~~691,~~769~~953.20

% Balance

10.4870%

0.2107%

0.0815%

10.7893%

# Loans

147

169

% # Loans

10.5580%

0.11%

1.7703%

FORECLOSURE

Balance

0159,012.0026

0.00

~~337,844~~0.4300

~~337~~159,~~844~~012.4326

% Balance

0.0009%

0.00%

0.1800%

0.1809%

# Loans

% # Loans

0.0011%

0.00%

0.1100%

0.11%

BANKRUPTCY

Balance

~~445~~695,~~146~~912.9850

0.00

~~445~~695,~~146~~912.9850

% Balance

0.2338%

0.00%

0.2338%

# Loans

% # Loans

0.2234%

0.00%

0.2234%

REO

Balance

0.00

% Balance

0.00%

# Loans

% # Loans

0.00%

TOTAL

Balance

~~445~~854,~~146~~924.9876

21,~~809~~279,~~272~~469.0579

~~404~~130,~~141~~701.4703

~~497~~281,~~200~~782.1138

42,~~155~~546,~~760~~877.6196

% Balance

0.2347%

10.4870%

0.2107%

0.2615%

21.1940%

# Loans

147

1913

% # Loans

0.2246%

10.5580%

0.11%

0.2211%

21.1049%

Page 10 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

REO Report

Loan Number

Original

Stated

Current

State &

First

Principal

Paid to

Note

LTV at

Original

Payment

Loan Group

Balance

Date

Rate

Origination

Term

Date

TOTAL

Page 11 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Foreclosure Report

Loan Number

Original

Stated

Current

State &

First

Principal

Paid to

Note

LTV at

Original

Payment

Loan Group

Balance

Date

Rate

Origination

Term

Date

120823758 1

120894390 1

340,000.00

337,844.43

01-Feb-2005

5.750%

NY - 79.07%

360

01-Mar-2005

160,200.00

159,012.26

01-Sep-2005

5.750%

NH - 89.00%

360

01-Apr-2005

TOTAL

~~340~~160,~~000~~200.00

~~337~~159,~~844~~012.4326

Page 12 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Prepayment Report

VOLUNTARY PREPAYMENTS

Total

Current

Number of Paid in Full Loans

2011

Number of Repurchased Loans

Total Number of Loans Prepaid in Full

2011

Curtailments Amount

~~375~~25,~~241~~610.0349

Paid in Full Balance

43,~~444~~093,~~989~~101.1358

Repurchased Loans Balance

0.00

Total Prepayment Amount

43,~~820~~118,~~230~~712.1607

Cumulative

Number of Paid in Full Loans

4877

Number of Repurchased Loans

Total Number of Loans Prepaid in Full

4877

Paid in Full Balance

1018,~~945~~346,~~937~~845.2359

Repurchased Loans Balance

0.00

Curtailments Amount

~~484~~542,~~286~~531.1254

Total Prepayment Amount

1118,~~430~~889,~~223~~377.3513

Page 13 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

VOLUNTARY PREPAYMENTS RATES

Total

SMM

21.4869%

3 Months Avg SMM

12.4615%

12 Months Avg SMM

1.1640%

Avg SMM Since Cut-off

1.1640%

CPR

2618.0045%

3 Months Avg CPR

1622.1997%

12 Months Avg CPR

1315.0955%

Avg CPR Since Cut-off

1315.0955%

PSA

1,~~980~~077.8244%

3 Months Avg PSA Approximation

1,~~452~~518.8272%

12 Months Avg PSA Approximation

1,~~430~~395.8397%

Avg PSA Since Cut-off Approximation

1,~~430~~395.8397%

Page 14 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

PREPAYMENT CALCULATION METHODOLOGY

Single Monthly Mortality (SMM): (Voluntary partial and full prepayments + Repurchases + Liquidations )/(Beg Principal Balance - Sched Principal) Conditional Prepayment Rate (CPR): 1-((1-SMM)^12) PSA Standard Prepayment Model: CPR/(0.002*min(30,WAS)) Average SMM over period between nth month and mth month (AvgSMMn,m): [(1-SMMn)*(1-SMMn+1)*...*(1-SMMm)]^(1/months in period n,m) Conditional Prepayment Rate (CPR): 1-((1-SMM)^12) Average PSA Approximation over period between the nth month and mth month: AvgCPRn,m/(0.002*Avg WASn,m)) Average WASn,m: (min(30,WASn)+min(30,WASn+1)+...+min(30,WASm)/(number of months in the period n,m) Weighted Average Seasoning (WAS) Dates correspond to distribution dates. Note: Prepayment rates are calculated since deal issue date and include partial and full voluntary prepayments, liquidations, and repurchases.

Page 15 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Prepayment Detail Report

Prepayment Detail Report - Mortgage Loans Prepaid in Full During Current Distribution

Loan Number

Original

Current

State &

Type Prepayment

First

Loan

Principal

Prepayment

Note

LTV at

Payment

Loan Group

Status

Balance

Amount

Date

Rate

Origination

Original Term

Date

3792935 1

109,155.00

108,123.88

20-Jul-2005

7.375%

MO - 95.00%

Paid Off - 360

01-Aug-2004

120380297 1

224,000.00

222,052.52

13-Oct-2005

5.625%

CA - 80.00%

Paid Off - 360

01-Feb-2005

120280452 1

187,600.00

186,303.93

03-Aug-2005

6.125%

NC - 80.00%

Paid Off - 360

01-Jan-2005

120380973 1

318,450.00

315,738.30

28-Sep-2005

6.375%

NV - 95.00%

Paid Off - 360

01-Jan-2005

120328951 1

256,319.00

254,835.94

12-Aug-2005

6.250%

CA - 80.00%

Paid Off - 360

01-Apr-2005

120381299 1

228,450.00

226,504.65

23-Sep-2005

6.375%

MI - 80.00%

Paid Off - 360

01-Jan-2005

120372446 1

282,150.00

281,873.40

19-Jul-2005

6.875%

MD - 95.00%

Paid Off - 360

01-Nov-2004

120381345 1

328,000.00

325,001.77

30-Sep-2005

6.000%

NJ - 75.40%

Paid Off - 360

01-Jan-2005

120373426 1

288,000.00

284,765.75

18-Jul-2005

6.125%

MA - 80.00%

Paid Off - 360

01-Nov-2004

120381626 1

328,000.00

327,906.71

22-Sep-2005

6.500%

CA - 80.00%

Paid Off - 360

01-Feb-2005

120377474 1

261,250.00

260,440.60

12-Aug-2005

7.250%

MD - 95.00%

Paid Off - 360

01-Dec-2004

120383515 1

225,600.00

14-Oct-2005

6.250%

IL - 80.00%

Paid Off - 360

01-Feb-2005

120380390 1

285,000.00

283,235.11

27-Jul-2005

5.875%

AZ - 54.81%

Paid Off - 360

01-Feb-2005

120384103 1

150,000.00

148,867.74

19-Sep-2005

6.375%

MD - 53.57%

Paid Off - 360

01-Feb-2005

120381431 1

191,369.00

191,055.45

10-Aug-2005

5.875%

CA - 80.00%

Paid Off - 360

01-Feb-2005

120660085 1

331,760.00

329,300.22

26-Sep-2005

5.750%

OR - 88.47%

Paid Off - 360

01-Mar-2005

120381534 1

114,800.00

114,153.51

25-Jul-2005

6.375%

CA - 80.00%

Paid Off - 360

01-Feb-2005

120811101 1

350,000.00

347,832.58

04-Oct-2005

5.875%

NY - 77.78%

Paid Off - 360

01-Apr-2005

120381596 1

220,000.00

02-Aug-2005

7.125%

CA - 80.00%

Paid Off - 360

01-Feb-2005

120867736 1

333,700.00

331,167.36

26-Sep-2005

5.625%

NV - 74.99%

Paid Off - 360

01-Mar-2005

120381660 1

450,000.00

449,999.99

10-Aug-2005

6.125%

CA - 65.00%

Paid Off - 360

01-Feb-2005

120920721 1

295,000.00

293,129.73

22-Sep-2005

5.750%

CA - 58.42%

Paid Off - 360

01-Apr-2005

120381680 1

233,000.00

09-Aug-2005

6.375%

WA - 80.00%

Paid Off - 360

01-Feb-2005

TOTAL

3,112,960.00

3,093,101.58

120382478 1

215,300.00

213,881.70

21-Jul-2005

6.375%

IL - 87.88%

Paid Off - 360

01-Jan-2005

120383989 1

110,023.00

109,298.21

15-Aug-2005

6.375%

VA - 50.01%

Paid Off - 360

01-Jan-2005

120784680 1

296,000.00

294,476.23

21-Jul-2005

5.875%

CA - 80.00%

Paid Off - 360

01-Mar-2005

120889936 1

252,000.00

250,988.98

27-Jul-2005

6.000%

IL - 72.00%

Paid Off - 360

01-Apr-2005

120912635 1

191,500.00

190,466.74

04-Aug-2005

5.625%

TN - 70.15%

Paid Off - 360

01-Mar-2005

120914787 1

150,000.00

149,369.05

29-Jul-2005

5.750%

CA - 39.47%

Paid Off - 360

01-Apr-2005

120924769 1

168,750.00

167,839.49

19-Jul-2005

5.625%

AZ - 75.00%

Paid Off - 360

01-Mar-2005

120997585 1

201,750.00

200,881.17

08-Aug-2005

5.625%

CA - 35.71%

Paid Off - 360

01-Apr-2005

TOTAL

4,463,966.00

4,444,989.13

Page 16 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Realized Loss Report

COLLATERAL REALIZED LOSSES

Total

Current

Number of Loans Liquidated

Collateral Principal Realized Loss/(Gain) Amount

0.00

Collateral Interest Realized Loss/(Gain) Amount

0.00

Net Liquidation Proceeds

~~0.00~~

Cumulative

Number of Loans Liquidated

Collateral Realized Loss/(Gain) Amount

0.00

Net Liquidation Proceeds

0.00

Special Hazard Loss Coverage Amt

1,~~946~~851,~~977~~941.8736

Fraud Loss Coverage Amt

2,522,545.60

Bankrupt Loss Coverage Amt

100,000.00

Class B-1 Writedown Amount

0.00

Class B-2 Writedown Amount

0.00

Class B-3 Writedown Amount

0.00

Class B-4 Writedown Amount

0.00

Class B-5 Writedown Amount

0.00

Class B-6 Writedown Amount

0.00

Page 17 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

DEFAULT SPEEDS

Total

MDR

0.00%

3 Months Avg MDR

0.00%

12 Months Avg MDR

0.00%

Avg MDR Since Cut-off

0.00%

CDR

0.00%

3 Months Avg CDR

0.00%

12 Months Avg CDR

0.00%

Avg CDR Since Cut-off

0.00%

SDA

0.00%

3 Months Avg SDA Approximation

0.00%

12 Months Avg SDA Approximation

0.00%

Avg SDA Since Cut-off Approximation

0.00%

Loss Severity Approximation for Current Period

0.00%

3 Months Avg Loss Severity Approximation

0.00%

12 Months Avg Loss Severity Approximation

0.00%

Avg Loss Severity Approximation Since Cut-off

0.00%

Page 18 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

COLLATERAL REALIZED LOSS CALCULATION METHODOLOGY

Monthly Default Rate (MDR): (Beg Principal Balance of Liquidated Loans)/(Total Beg Principal Balance)

Conditional Default Rate (CDR): 1-((1-MDR)^12)

SDA Standard Default Assumption: CDR/IF(WAS<61,MIN(30,WAS)*0.02,MAX(0.03,MIN(30,WAS)*0.02-0.0095*(WAS-60)))

Average MDR over period between nth month and mth month (AvgMDRn,m): [(1-MDRn)*(1-MDRn+1)*...*(1-MDRm)]^(1/months in period n,m)

Average CDR over period between the nth month and mth month (AvgCDRn,m): 1-((1-AvgMDRn,m)^12)

Average SDA Approximation over period between the nth month and mth month:

AvgCDRn,m/IF(Avg WASn,m<61,MIN(30,Avg WASn,m)*0.02,MAX(0.03,MIN(30,Avg WASn,m)*0.02-0.0095*(Avg WASn,m-60)))

Average WASn,m: (WASn + WASn+1 +...+ WASm )/(number of months in the period n,m)

Loss Severity Approximation for current period: sum(Realized Loss Amount)/sum(Beg Principal Balance of Liquidated Loans)

Average Loss Severity Approximation over period between nth month and mth month: Avg(Loss Severityn,m)

Note: Default rates are calculated since deal issue date and include realized gains and additional realized losses and gains from prior periods.

Dates correspond to distribution dates.

Page 19 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Realized Loss Detail Report

Loan Number

Current

State &

Prior

Realized

Cumulative

Loan

Note

LTV at

Original

Principal

Loss/(Gain)

Realized

Loan Group

Status

Rate

Origination

Term

Balance

Revision

Loss/(Gain)

TOTAL

Page 20 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Triggers and Adj. Cert. Report

TRIGGER EVENTS

Total

Has Optional Termination Date Reached (0=No,1=Yes)

Has Sr. Prepay Stepdown Condition Occurred

Has Sr. Credit Supp. Depletion Date Occured

Have all Prepayment Penalties Expired? (0=No,1=Yes)

Has Special Haz. Cov. Term Date Occured

Has Fraud Loss Coverage Term Date Occured

Has BK Loss Cov. Term Date Occured (0=No,1=Yes)

ADJUSTABLE RATE CERTIFICATE INFORMATION

SPACE INTENTIONALLY LEFT BLANK

ADDITIONAL INFORMATION

Total

Current Senior Percentage

95.~~315683~~083317%

Next Senior Percentage

9594.~~196203~~998844%

Current Subordinate Percentage

4.~~684317~~916683%

Next Subordinate Percentage

45.~~803797~~001156%

Senior Prepayment Percentage

100.000000%

Next Senior Prepayment Percentage

100.000000%

Subordinate Prepayment Percentage

0.000000%

Next Subordinate Prepayment Percentage

0.000000%

Page 21 of 22

IndyMac Residential Asset Securitization Trust 2005-A4

Mortgage Pass-Through Certificates

2005-A4

August 25, 2005 Distribution

October 25, 2005 Distribution

Other Related Information

ADDITIONAL INFORMATION

Total

Current Scheduled Payments

1,~~144~~091,~~899~~285.4940

Current Scheduled Payments 1 Month Prior

1,~~156~~115,~~041~~640.9426

Current Scheduled Payments 2 Month Prior

1,~~168~~144,~~295~~899.4449

Current Scheduled Payments 3 Month Prior

1,~~179~~156,~~181~~041.8494

Current Scheduled Payments 4 Month Prior

1,~~187~~168,~~328~~295.3644

Current Scheduled Payments 5 Month Prior

01,179,181.0084

Current Scheduled Payments 6 Month Prior

01,187,328.0036

Current Scheduled Payments 7 Month Prior

0.00

Current Scheduled Payments 8 Month Prior

0.00

Current Scheduled Payments 9 Month Prior

0.00

Current Scheduled Payments 10 Month Prior

0.00

Current Scheduled Payments 11 Month Prior

0.00

Delinquent 60+ Scheduled Payments

87,~~186~~485.5039

Delinq. 60+ Sched. Pmnts, 1 Month Prior

511,~~783~~068.3927

Delinq. 60+ Sched. Pmnts, 2 Month Prior

48,~~208~~186.50

Delinq. 60+ Sched. Pmnts, 3 Month Prior

15,~~984~~783.1539

Delinq. 60+ Sched. Pmnts, 4 Month Prior

04,208.0050

Delinq. 60+ Sched. Pmnts, 5 Month Prior

01,984.0015

Delinq. 60+ Sched. Pmnts, 6 Month Prior

0.00

Delinq. 60+ Sched. Pmnts, 7 Month Prior

0.00

Delinq. 60+ Sched. Pmnts, 8 Month Prior

0.00

Delinq. 60+ Sched. Pmnts, 9 Month Prior

0.00

Delinq. 60+ Sched. Pmnts, 10 Month Prior

0.00

Delinq. 60+ Sched. Pmnts, 11 Month Prior

0.00

Variable Rate Certificates - Next PTR Details:

Next Period Pass Through Rate - Class A-1

0.450000%

Next Period Pass Through Rate - Class A-2

1.~~590000~~220000%

Payments Received from CAP Contract

0.00

CAP Contract Strike Rate:5.05%

Page 22 of 22

Filing Compare · IndyMac RAST 2005-A4