IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

External Parties

Table of Contents

Page

Seller

1. Certificate Payment Report

IndyMac Bank

2. Collection Account Report

3. Credit Enhancement Report

Servicer(s)

4. Collateral Report

IndyMac Bank

5. Delinquency Report

6. REO Report

Underwriter(s)

7. Foreclosure Report

Banc of America Securities LLC

8. Prepayment Report

Credit Suisse Securities (USA) LLC

9. Prepayment Detail Report

10. Realized Loss Report

11. Realized Loss Detail Report

12. Triggers and Adj. Cert. Report

13. Other Related Information

Total Number of Pages

Dates

Contacts

Cut-Off Date:

September 01, 2007

Jennifer Hermansader

Close Date:

September 25, 2007

Administrator

First Distribution Date:

October 25, 2007

(714) 247-6258

Jennifer.Vandyne@db.com

Address:

Distribution Date:

December 26, 2007

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

Record Date:

November 30, 2007

Factor Information:

(800) 735-7777

Main Phone Number:

(714) 247-6000

Determination Date:

December 17, 2007

https://tss.sfs.db.com/investpublic

Page 1 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
December 26, 2007 Distribution

Certificate Payment Report
Current Period Distribution - REMIC I
			Prior						Current
			Prior

	Class	Original	Principal			Total	Realized	Deferred	Principal

Class	Type	Face Value	Balance	Interest	Principal	Distribution	Loss	Interest	Balance
			(1)	(2)	(3)	(4)=(2)+(3)	(5)	(6)	(7)=(1)-(3)-(5)+(6)
A-1	SR	200,329,000.00	197,980,093.82	1,031,146.32	3,143,981.74	4,175,128.06	0.00	0.00	194,836,112.08
A-1	SR	200,329,000.00	197,980,093.82	1,031,146.32	3,143,981.74	4,175,128.06	0.00	0.00	194,836,112.08
A-2	SR	9,214,900.00	9,106,853.05	47,431.53	144,619.49	192,051.02	0.00	0.00	8,962,233.56
PO	SR	2,120,257.66	2,117,477.82	0.00	1,371.18	1,371.18	0.00	0.00	2,116,106.64
A-X	NTL/SR	0.00	0.00	83,153.32	0.00	83,153.32	0.00	0.00	0.00
A-R	SR/RES	100.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
B-1	SUB	6,003,000.00	5,997,088.73	31,234.84	2,775.91	34,010.75	0.00	0.00	5,994,312.82
B-2	SUB	1,556,000.00	1,554,467.77	8,096.19	719.53	8,815.72	0.00	0.00	1,553,748.24
B-3	SUB	1,112,000.00	1,110,904.99	5,785.96	514.21	6,300.17	0.00	0.00	1,110,390.78
B-4	SUB	778,000.00	777,233.89	4,048.09	359.76	4,407.85	0.00	0.00	776,874.13
B-5	SUB	778,000.00	777,233.89	4,048.09	359.76	4,407.85	0.00	0.00	776,874.13
B-6	SUB	445,566.00	445,127.23	2,318.37	206.04	2,524.41	0.00	0.00	444,921.19
P	NOF	100.00	100.00	1,542.79	0.00	1,542.79	0.00	0.00	100.00
L	NOF	0.00	0.00	35.67	0.00	35.67	0.00	0.00	0.00


Total		222,336,923.66	219,866,581.19	1,218,841.17	3,294,907.62	4,513,748.79	0.00	0.00	216,571,673.57
Total




Interest Accrual Detail Current Period Factor Information per $1,000 of Original Face Value
					Orig. Principal	Prior				Current
					Orig. Principal	Prior				Current
	Period	Period			(with Notional)	Principal			Total	Principal
Class	Starting	Ending	Method	Cusip	Balance	Balance	Interest	Principal	Distribution	Balance
			Method
					(1)	(1)	(2)	(3)	(4)=(2)+(3)	(5)

A-1	11/01/07	11/30/07	F-30/360	456669AA8	200,329,000.00	988.274757	5.147264	15.694092	20.841356	972.580665
A-1	11/01/07	11/30/07	F-30/360	456669AA8	200,329,000.00	988.274757	5.147264	15.694092	20.841356	972.580665
A-2	11/01/07	11/30/07	F-30/360	456669AB6	9,214,900.00	988.274756	5.147265	15.694092	20.841357	972.580664
PO		456669AC4	2,120,257.66	998.688914	0.000000	0.646704	0.646704	998.042210
A-X	11/01/07	11/30/07	F-30/360	456669AD2	175,468,670.00	986.247506	0.473893	0.000000	0.473893	967.629847
A-R	11/01/07	11/30/07	F-30/360	456669AE0	100.00	0.000000	0.000000	0.000000	0.000000	0.000000
B-1	11/01/07	11/30/07	F-30/360	456669AF7	6,003,000.00	999.015281	5.203205	0.462420	5.665626	998.552860
B-2	11/01/07	11/30/07	F-30/360	456669AG5	1,556,000.00	999.015276	5.203207	0.462423	5.665630	998.552853
B-3	11/01/07	11/30/07	F-30/360	456669AH3	1,112,000.00	999.015279	5.203201	0.462419	5.665621	998.552860
B-4	11/01/07	11/30/07	F-30/360	456669AJ9	778,000.00	999.015283	5.203201	0.462416	5.665617	998.552866
B-5	11/01/07	11/30/07	F-30/360	456669AK6	778,000.00	999.015283	5.203201	0.462416	5.665617	998.552866
B-6	11/01/07	11/30/07	F-30/360	456669AL4	445,566.00	999.015253	5.203202	0.462423	5.665625	998.552829
P		456669AM2	100.00	1,000.000000	15,427.900000	0.000000	15,427.900000	1,000.000000
L		456669AN0	0.00	0.000000	0.000000	0.000000	0.000000	0.000000




Page 2 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
December 26, 2007 Distribution


Distribution to Date - REMIC I
									Current


	Original		Unscheduled	Scheduled	Total	Total	Realized	Deferred	Principal

Class	Face Value	Interest	Principal	Principal	Principal	Distribution	Loss	Interest	Balance
(1)	(2)	(3)	(4)	(5)=(3)+(4)	(6)=(2)+(5)	(7)	(8)	(9)=(1)-(5)-(7)+(8)
A-1	200,329,000.00	3,117,060.39	5,204,235.12	288,652.80	5,492,887.92	8,609,948.31	0.00	0.00	194,836,112.08
A-2	9,214,900.00	143,381.14	239,388.74	13,277.69	252,666.44	396,047.58	0.00	0.00	8,962,233.56
PO	2,120,257.66	0.00	555.60	3,595.42	4,151.02	4,151.02	0.00	0.00	2,116,106.64
A-X	0.00	251,769.00	0.00	0.00	0.00	251,769.00	0.00	0.00	0.00
A-R	100.00	0.52	35.59	64.41	100.00	100.52	0.00	0.00	0.00
B-1	6,003,000.00	93,749.74	0.00	8,687.18	8,687.18	102,436.92	0.00	0.00	5,994,312.82
B-2	1,556,000.00	24,300.29	0.00	2,251.76	2,251.76	26,552.05	0.00	0.00	1,553,748.24
B-3	1,112,000.00	17,366.27	0.00	1,609.22	1,609.22	18,975.49	0.00	0.00	1,110,390.78
B-4	778,000.00	12,150.13	0.00	1,125.87	1,125.87	13,276.00	0.00	0.00	776,874.13
B-5	778,000.00	12,150.13	0.00	1,125.87	1,125.87	13,276.00	0.00	0.00	776,874.13
B-6	445,566.00	6,958.47	0.00	644.80	644.80	7,603.27	0.01	0.00	444,921.19
P	100.00	1,542.79	0.00	0.00	0.00	1,542.79	0.00	0.00	100.00
L	0.00	838.90	0.00	0.00	0.00	838.90	0.00	0.00	0.00


Total	222,336,923.66	3,681,267.77	5,444,215.05	321,035.02	5,765,250.08	9,446,517.85	0.01	0.00	216,571,673.57


Interest Detail - REMIC I
	Pass	Prior Principal		Non-	Prior	Unscheduled		Paid or	Current
	Pass	Prior Principal		Non-	Prior	Unscheduled		Paid or

	Through	(with Notional)	Accrued	Supported	Unpaid	Interest	Optimal	Deferred	Unpaid

Class	Rate	Balance	Interest	Interest SF	Interest	Adjustment	Interest	Interest	Interest
			(1)	(2)	(3)	(4)	(5)=(1)-(2)+(3)+(4)	(6)	(7)=(5)-(6)
A-1	6.25000%	197,980,093.82	1,031,146.32	0.00	0.00	0.00	1,031,146.32	1,031,146.32	0.00
A-2	6.25000%	9,106,853.05	47,431.53	0.00	0.00	0.00	47,431.53	47,431.53	0.00
PO	0.00000%	2,117,477.82	0.00	0.00	0.00	0.00	0.00	0.00	0.00
A-X	0.57660%	173,055,538.25	83,153.32	0.00	0.00	0.00	83,153.32	83,153.32	0.00
A-R	0.00000%	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
B-1	6.25000%	5,997,088.73	31,234.84	0.00	0.00	0.00	31,234.84	31,234.84	0.00
B-2	6.25000%	1,554,467.77	8,096.19	0.00	0.00	0.00	8,096.19	8,096.19	0.00
B-3	6.25000%	1,110,904.99	5,785.96	0.00	0.00	0.00	5,785.96	5,785.96	0.00
B-4	6.25000%	777,233.89	4,048.09	0.00	0.00	0.00	4,048.09	4,048.09	0.00
B-5	6.25000%	777,233.89	4,048.09	0.00	0.00	0.00	4,048.09	4,048.09	0.00
B-6	6.25000%	445,127.23	2,318.37	0.00	0.00	0.00	2,318.37	2,318.37	0.00
P	18,513.48000%	100.00	0.00	0.00	0.00	0.00	0.00	1,542.79	0.00
L	0.00000%	0.00	0.00	0.00	0.00	0.00	0.00	35.67	0.00


Total		392,922,119.44	1,217,262.71	0.00	0.00	0.00	1,217,262.71	1,218,841.17	0.00



Page 3 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

Collection Account Report

SUMMARY

Total

Principal Collections

3,294,907.63

Principal Withdrawals

0.00

Principal Other Accounts

0.00

TOTAL NET PRINCIPAL

3,294,907.63

Interest Collections

1,248,677.76

Interest Withdrawals

-0.00

Interest Other Accounts

1,578.46

Interest Fees

-31,415.05

TOTAL NET INTEREST

1,218,841.17

TOTAL AVAILABLE FUNDS FOR DISTRIBUTION

4,513,748.80

PRINCIPAL - COLLECTIONS

Total

Scheduled Principal Received

101,995.63

Curtailments

104,343.29

Prepayments In Full

3,088,568.71

Repurchased/Substitutions

0.00

Liquidations

0.00

Insurance Principal

0.00

Other Additional Principal

0.00

Delinquent Principal

-21,075.22

Realized Losses

-0.00

Advanced Principal

21,075.22

TOTAL PRINCIPAL COLLECTED

3,294,907.63

PRINCIPAL - WITHDRAWALS

SPACE INTENTIONALLY LEFT BLANK

PRINCIPAL - OTHER ACCOUNTS

Total

TOTAL PRINCIPAL OTHER ACCOUNTS

0.00

Page 4 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

INTEREST - COLLECTIONS

Total

Scheduled Interest

1,257,689.81

Repurchased/Substitution Interest

0.00

Liquidation Interest

0.00

Insurance Interest

0.00

Other Additional Interest

0.00

Prepayment Interest Shortfalls

-1,295.90

Delinquent Interest

-307,582.85

Compensating Interest

1,295.90

Civil Relief Act Shortfalls

0.00

Interest Advanced

298,570.81

TOTAL INTEREST COLLECTED

1,248,677.76

INTEREST - WITHDRAWALS

Total

Interest Withdrawals

0.00

INTEREST - OTHER ACCOUNTS

Total

Prepayment Charges

1,542.79

Late Payment Fee paid by the servicer

35.67

TOTAL INTEREST OTHER ACCOUNTS

1,578.46

Late Payment Fee waived

507.38

INTEREST FEES

Total

Current Servicing Fees

29,582.82

Trustee Fees

1,832.22

TOTAL INTEREST FEES

31,415.05

Page 5 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

Credit Enhancement Report

ACCOUNTS

Distribution Account

Beginning Account Balance

0.00

Amount Deposited

4,515,580.99

Amount Withdrawn

4,515,580.99

Ending Account Balance

0.00

INSURANCE

SPACE INTENTIONALLY LEFT BLANK

STRUCTURAL FEATURES

SPACE INTENTIONALLY LEFT BLANK

Page 6 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

Collateral Report

COLLATERAL

Total

Loan Count:

Original

314

Prior

313

Prefunding

Scheduled Paid Offs

-0

Full Voluntary Prepayments

-3

Repurchases

-0

Liquidations

-0

Current

310

Principal Balance:

Original

222,336,824.44

Prior

219,866,481.20

Prefunding

0.00

Substitution Loans

0.00

Scheduled Principal

-101,995.63

Partial Prepayments

-104,343.29

Full Voluntary Prepayments

-3,088,568.71

Repurchases

-0.00

Liquidations

-0.00

Current

216,571,573.57

Aggregate number and outstanding Stated Principal

of Mortgage Loans repurchased during the related

Due Period due to material breaches of representations

and warranties regarding such Mortgage Loans*

* Information not available with Trustee

PREFUNDING

SPACE INTENTIONALLY LEFT BLANK

Page 7 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution



CHARACTERISTICS
CHARACTERISTICS

							Total
Weighted Average Coupon Original							6.86613%
Weighted Average Coupon Prior							6.86615%
Weighted Average Coupon Current							6.86429%
Weighted Average Months to Maturity Original							356
Weighted Average Months to Maturity Prior							355
Weighted Average Months to Maturity Current							355
Weighted Avg Remaining Amortization Term Original							356
Weighted Avg Remaining Amortization Term Prior							355
Weighted Avg Remaining Amortization Term Current							355
Weighted Average Seasoning Original							2.08
Weighted Average Seasoning Prior							3.09
Weighted Average Seasoning Current							4.11

Page 8 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution



ARM CHARACTERISTICS
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%





Page 9 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

SERVICING FEES & ADVANCES

Total

Current Servicing Fees

29,582.82

Delinquent Servicing Fees

9,012.04

TOTAL SERVICING FEES

38,594.87

Total Servicing Fees

38,594.87

Compensating Interest

-1,295.90

Delinquent Servicing Fees

-9,012.04

COLLECTED SERVICING FEES

28,286.93

Total Advanced Interest

298,570.81

Total Advanced Principal

21,075.22

Aggregate Advances with respect to this Distribution

319,646.02

Aggregate Advances Outstanding on the close of distribution

0.00

Any additional servicing compensation received by the

Servicer attributable to penalties, fees, Excess Proceeds

or other similar charges or fees and items. *

The aggregate amount of Advances reimbursed

during the related Due Period. *

The general source of funds for such reimbursements. *

The aggregate amount of Advances outstanding as

of the close of business on the Distribution Date. *

The aggregate amount of Servicing Advances

reimbursed during the related Due Period. *

The general source of funds for such reimbursements. *

The aggregate amount of Servicing Advances outstanding

as of the close of business on the Distribution Date. *

* Information not available with Trustee

ADDITIONAL COLLATERAL INFORMATION

Total

Prepayment Interest Shortfall (PPIS)

1,295.90

Compensating Interest

(1,295.90)

Net Prepayment Interest Shortfall (PPIS)

0.00

Weighted Average Net Mortgage Rate

6.643647%

Page 10 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
December 26, 2007 Distribution

Delinquency Report

TOTAL
		< 1 PAYMENT	1 PAYMENT	2 PAYMENTS	3+ PAYMENTS	TOTAL
DELINQUENT	Balance		1,177,432.57	997,286.85	880,000.00	3,054,719.42
	% Balance		0.54%	0.46%	0.41%	1.41%
	# Loans		2	2	1	5
	% # Loans		0.65%	0.65%	0.32%	1.61%
FORECLOSURE	Balance	0.00	0.00	0.00	0.00	0.00
	% Balance	0.00%	0.00%	0.00%	0.00%	0.00%
	# Loans	0	0	0	0	0
	% # Loans	0.00%	0.00%	0.00%	0.00%	0.00%
BANKRUPTCY	Balance	0.00	0.00	0.00	0.00	0.00
	% Balance	0.00%	0.00%	0.00%	0.00%	0.00%
	# Loans	0	0	0	0	0
	% # Loans	0.00%	0.00%	0.00%	0.00%	0.00%
REO	Balance	0.00	0.00	0.00	0.00	0.00
	% Balance	0.00%	0.00%	0.00%	0.00%	0.00%
	# Loans	0	0	0	0	0
	% # Loans	0.00%	0.00%	0.00%	0.00%	0.00%
TOTAL	Balance	0.00	1,177,432.57	997,286.85	880,000.00	3,054,719.42
	% Balance	0.00%	0.54%	0.46%	0.41%	1.41%
	# Loans	0	2	2	1	5
	% # Loans	0.00%	0.65%	0.65%	0.32%	1.61%

Page 11 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 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

Page 12 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 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

Page 13 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

Prepayment Report

VOLUNTARY PREPAYMENTS

Total

Current

Number of Paid in Full Loans

Number of Repurchased Loans

Total Number of Loans Prepaid in Full

Curtailments Amount

104,343.29

Paid in Full Balance

3,088,568.71

Repurchased Loans Balance

0.00

Total Prepayment Amount

3,192,912.00

Cumulative

Number of Paid in Full Loans

Number of Repurchased Loans

Total Number of Loans Prepaid in Full

Paid in Full Balance

4,087,807.79

Repurchased Loans Balance

0.00

Curtailments Amount

1,356,232.40

Total Prepayment Amount

5,444,040.19

Page 14 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
December 26, 2007 Distribution


VOLUNTARY PREPAYMENTS RATES - Including Liquidated Balances



		Total





SMM	1.45%
3 Months Avg SMM	0.82%
12 Months Avg SMM	0.82%
Avg SMM Since Cut-off	0.82%



CPR	16.11%
3 Months Avg CPR	9.45%
12 Months Avg CPR	9.45%
Avg CPR Since Cut-off	9.45%



PSA	1,961.51%
3 Months Avg PSA Approximation	1,527.90%
12 Months Avg PSA Approximation	1,527.90%
Avg PSA Since Cut-off Approximation	1,527.91%


(*) SMM, CPR, PSA Figures Include Liquidated Balances

Page 15 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

PREPAYMENT CALCULATION METHODOLOGY - Including Liquidated Balances

Single Monthly Mortality (SMM): (Voluntary partial and full prepayments + Repurchases + Liquidated Balances)/(Beg Principal Balance - Sched Principal)

Conditional Prepayment Rate (CPR): 1-((1-SMM)^12)

PSA Standard Prepayment Model: CPR/(0.20%*min(30,WAS))

Average SMM over period between nth month and mth month (AvgSMMn,m): 1 - [(1-SMMn)*(1-SMMn+1)*...*(1-SMMm)]^(1/months in period n,m)

Average CPR over period between the nth month and mth month (AvgCPRn,m): 1-((1-AvgSMMn,m)^12)

Average PSA Approximation over period between the nth month and mth month: AvgCPRn,m/(0.20%*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)

Note: Prepayment rates are calculated since deal issue date and include partial and full voluntary prepayments and repurchases.

Dates correspond to distribution dates.

Page 16 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

VOLUNTARY PREPAYMENTS RATES - Excluding Liquidated Balances

Total

SMM

1.45%

3 Months Avg SMM

0.82%

12 Months Avg SMM

0.82%

Avg SMM Since Cut-off

0.82%

CPR

16.11%

3 Months Avg CPR

9.45%

12 Months Avg CPR

9.45%

Avg CPR Since Cut-off

9.45%

PSA

1,961.51%

3 Months Avg PSA Approximation

1,527.90%

12 Months Avg PSA Approximation

1,527.90%

Avg PSA Since Cut-off Approximation

1,527.91%

(*) SMM, CPR, PSA Figures Exclude Liquidated Balances

Page 17 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

PREPAYMENT CALCULATION METHODOLOGY - Excluding Liquidated Balances

Single Monthly Mortality (SMM): (Voluntary partial and full prepayments + Repurchases)/(Beg Principal Balance - Sched Principal)

Conditional Prepayment Rate (CPR): 1-((1-SMM)^12)

PSA Standard Prepayment Model: CPR/(0.20%*min(30,WAS))

Average SMM over period between nth month and mth month (AvgSMMn,m): 1 - [(1-SMMn)*(1-SMMn+1)*...*(1-SMMm)]^(1/months in period n,m)

Average CPR over period between the nth month and mth month (AvgCPRn,m): 1-((1-AvgSMMn,m)^12)

Average PSA Approximation over period between the nth month and mth month: AvgCPRn,m/(0.20%*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)

Note: Prepayment rates are calculated since deal issue date and include partial and full voluntary prepayments and repurchases.

Dates correspond to distribution dates.

Page 18 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 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

126761439 1

1,500,000.00

1,497,472.42

11-Dec-2007

6.875%

MA - 52.91%

Paid Off - 360

01-Oct-2007

127242547 1

592,000.00

591,096.29

20-Nov-2007

7.375%

CA - 80.00%

Paid Off - 360

01-Oct-2007

127300473 1

1,000,000.00

12-Dec-2007

7.625%

CA - 62.31%

Paid Off - 360

01-Oct-2007

TOTAL

3,092,000.00

3,088,568.71

Page 19 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
December 26, 2007 Distribution

Realized Loss Report

COLLATERAL REALIZED LOSSES


		Total


Current





	Subsequent Recoveries		0.00

	Number of Loans Liquidated		0
	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		0

	Collateral Realized Loss/(Gain) Amount		0.00
	Net Liquidation Proceeds		0.00
Cumulative Subsequent Recoveries		0.00



	Special Hazard Loss Coverage Amt		4,392,765.68
	Fraud Loss Coverage Amt		2,223,368.00
	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 20 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
December 26, 2007 Distribution


DEFAULT SPEEDS
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%


Principal Only Loss Severity Approx 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%


Principal & Interest Loss Severity Approx 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 21 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 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)

Principal Only Loss Severity Approximation for current period:

Sum(Principal Realized Loss Amount)/sum(Beg Principal Balance of Liquidated Loans)

Principal & Interest Loss Severity Approximation for current period:

Sum(Principal & Interest Realized Loss Amount)/sum(Beg Principal Balance of Liquidated Loans)

Average Loss Severity Approximation over period between nth month and mth month:

Sum(Realized Loss Amount)/sum(Beg Principal Balance of Liquidated Loans for months in the period n,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.

All Realized Losses in excess of Principal Balance are treated as Interest Realized Losses.

Page 22 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 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 23 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3

Mortgage Pass-Through Certificates

December 26, 2007 Distribution

Triggers and Adj. Cert. Report

TRIGGER EVENTS

Total

Has Optional Termination Date Reached ?

Has Sr. Credit Supp. Depletion Date Occured ?

Has Special Haz. Cov. Term Date Occured ?

Has Fraud Loss Coverage Term Date Occured ?

Has BK Loss Cov. Term Date Occured ?

Does an Event of Default Exist?

Senior Stepdown Date has occurred?

Sr.Stepdown Cond Satisfied?(1=Yes or 2=Yes)

1.Delinquency Trigger

Does Delinquency Trigger Event Exist (a > 50% of b)

(a) Rolling Six Month 60+ Delq Balance

459,547.81

(b) Aggregate Balance of Subordinate Certificates

10,657,121.29

2.Cumulative Loss Trigger

Does a Loss Trigger Event Exist (a > b)

(a) Cumulative Realized Loss

0.00

(b) Cumulative Loss Threshold (i)*(ii)

10,672,566.00

(i) Threshold Percentage

100.0000%

(ii) Cutoff Date Subordinate Principal Balance

10,672,566.00

ADJUSTABLE RATE CERTIFICATE INFORMATION

SPACE INTENTIONALLY LEFT BLANK

ADDITIONAL INFORMATION

Total

Senior Percentage

95.103511%

Subordinate Percentage

4.896489%

Senior Prepayment Percentage

100.000000%

Subordinate Prepayment Percentage

0.000000%

Page 24 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
December 26, 2007 Distribution

Other Related Information
ADDITIONAL INFORMATION
ADDITIONAL INFORMATION
							Total
Current Scheduled Payments							1,359,685.44
Current Scheduled Payments 1 Month Prior							1,373,988.24
Current Scheduled Payments 2 Month Prior							1,388,540.83
Current Scheduled Payments 3 Month Prior							0.00
Current Scheduled Payments 4 Month Prior							0.00
Current Scheduled Payments 5 Month Prior							0.00
Current Scheduled Payments 6 Month Prior							0.00
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							12,364.25
Delinq. 60+ Sched. Pmnts, 1 Month Prior							5,500.00
Delinq. 60+ Sched. Pmnts, 2 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 3 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 4 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 5 Month Prior							0.00
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





Page 25 of 25

IndyMac IMJA Mortgage Loan Trust 2007-A3 10-D