Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Summary Collateral Information
	Description
Group 1
Pool 8108	HYBRID ARM

General Information
Description	Total	Pool 8108
Weighted Average Pass Through Rate	6.57240%	6.57240%
Weighted Average Mortgage Interest Rate	6.96382%	6.96382%
Weighted Average Remaining Term (in Months)	352.48823	352.48823
Weighted Average Loan Age (in Months)	9.19648	9.19648
Average Ending Scheduled Principal Balance	$293,547.31	$293,547.31
Remaining Loan Count	1702	1702
Ending Scheduled Principal Balance	$499,617,514.88	$499,617,514.88

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Geographic Distribution
Total			Pool 8108
State	Percent	Ending Scheduled Principal Balance	State	Percent	Ending Scheduled Principal Balance
CA	$240,202,548.23	48.08%	CA	$240,202,548.23	48.08%
FL	$72,266,513.70	14.46%	FL	$72,266,513.70	14.46%
IL	$33,252,211.51	6.66%	IL	$33,252,211.51	6.66%
AZ	$22,074,254.08	4.42%	AZ	$22,074,254.08	4.42%
MD	$15,815,352.44	3.17%	MD	$15,815,352.44	3.17%
OTHER	$116,006,634.92	23.22%	OTHER	$116,006,634.92	23.22%

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Prepayment Information (all groups)
	1 Month	3 Month	6 Month	12 Month	Cumulative
PSA	97.89027%	396.78354%	535.63746%	535.63746%	535.63698%
CPR	1.80049%	6.50422%	7.17635%	7.17635%	7.17634%
SMM	0.15129%	0.55888%	0.61865%	0.61865%	0.61865%

Trigger Events
	Trigger Flag
Optional Termination Date Has Occurred; 1=Yes, 0=No	0
Step Down Date Has Occurred; 1=Yes, 0=No	0
Senior Credit Support Depletion Date Has Occurred; 1=Yes, 0=No	0

Comments

1. The Subordinate Certificates provide, to the limited extent described in the Prospectus Supplement, credit support, to certain Senior Certificates. The "Prospectus Supplement" is that certain Prospectus Supplement, dated May 2, 2007 to that certain Prospectus, dated April 17, 2007, pursuant to which the Senior Certificates were offered.

2. The MBA method of delinquency calculation is used.

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Certificate Payment Summary Report
Class	CUSIP	Original Principal/Notional Balance	Beginning Principal/Notional Balance	Interest Distribution	Principal Distribution	Principal Loss	Deferred Interest	Total Distribution	Ending Principal/Notional Balance
A1	93936FAA8	$250,000,000.00	$240,185,272.54	$1,074,936.49	$448,008.09	$0.00	$0.00	$1,522,944.58	$239,737,264.45
A2	93936FAB6	$89,064,000.00	$82,573,402.96	$361,296.65	$296,273.13	$0.00	$0.00	$657,569.78	$82,277,129.83
A3	93936FAC4	$42,693,000.00	$42,693,000.00	$190,714.53	$0.00	$0.00	$0.00	$190,714.53	$42,693,000.00
A4	93936FAD2	$33,571,000.00	$33,571,000.00	$152,483.01	$0.00	$0.00	$0.00	$152,483.01	$33,571,000.00
A5	93936FAS9	$60,741,000.00	$58,356,374.57	$265,060.78	$108,849.84	$0.00	$0.00	$373,910.62	$58,247,524.73
M1	93936FAE0	$8,307,000.00	$8,307,000.00	$38,631.07	$0.00	$0.00	$0.00	$38,631.07	$8,307,000.00
M2	93936FAF7	$7,268,000.00	$7,268,000.00	$34,404.87	$0.00	$0.00	$0.00	$34,404.87	$7,268,000.00
M3	93936FAG5	$4,413,000.00	$4,413,000.00	$21,441.58	$0.00	$0.00	$0.00	$21,441.58	$4,413,000.00
M4	93936FAH3	$3,894,000.00	$3,894,000.00	$20,704.41	$0.00	$0.00	$0.00	$20,704.41	$3,894,000.00
M5	93936FAJ9	$3,634,000.00	$3,634,000.00	$20,078.97	$0.00	$0.00	$0.00	$20,078.97	$3,634,000.00
M6	93936FAK6	$2,596,000.00	$2,596,000.00	$14,884.51	$0.00	$0.00	$0.00	$14,884.51	$2,596,000.00
B1	93936FAL4	$2,596,000.00	$2,596,000.00	$15,425.35	$0.00	$0.00	$0.00	$15,425.35	$2,596,000.00

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Certificate Payment Summary Report (Continued)
Class	CUSIP	Original Principal/Notional Balance	Beginning Principal/Notional Balance	Interest Distribution	Principal Distribution	Principal Loss	Deferred Interest	Total Distribution	Ending Principal/Notional Balance
B2	93936FAM2	$2,596,000.00	$2,596,000.00	$15,425.35	$0.00	$0.00	$0.00	$15,425.35	$2,596,000.00
B3	93936FAN0	$2,596,000.00	$2,596,000.00	$15,425.35	$0.00	$0.00	$0.00	$15,425.35	$2,596,000.00
C	93936FAQ3	$5,190,486.00	$5,191,594.93	$551,729.85	($0.01)	$0.00	$0.00	$551,729.84	$5,191,594.94
R	93936FAP5	$100.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
PPP	93936FAR1	$0.00	$500,470,645.93	$0.00	$0.00	$0.00	$0.00	$0.00	$499,617,514.88
R_SYN	XXXXXXXXX	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
TFEE	XXXXXXXXX	$0.00	$0.00	$500.47	$0.00	$0.00	$0.00	$500.47	$0.00
SWAP_PAYMENT	XXXXXXXXX	$0.00	$0.00	($51,862.84)	$0.00	$0.00	$0.00	($51,862.84)	$0.00
Total*		$519,159,586.00	$500,470,645.00	$2,792,642.75	$853,131.05	$0.00	$0.00	$3,645,773.82	$499,617,513.95

*Total balances exclude notional balances.

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Total Funds Available for Distribution
PRINCIPAL BALANCE
Scheduled Principal Received or Advanced	$96,096.43
Unscheduled Principal	$42,765.85
Prepayments in Full	$714,268.77
Repurchases	$0.00
Liquidations	$0.00
Total Principal	$853,131.05
INTEREST
Accrued Interest at Gross Rate	$2,904,322.66
Relief Act Shortfall	$297.10
Prepayment Interest Shortfall	$0.00
Servicing Fees	$163,245.44
Other	$0.00
Total Interest	$2,740,779.90
ADDITIONAL FUNDS
Excess Liquidation Proceeds	$0.00
Subsequent Recoveries	$0.00
Prepayment Penalties	$0.00

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Total Funds Available for Distribution
ADDITIONAL FUNDS
Other	$0.00
Total Additional Funds	$0.00
Total Funds Available for Distribution	$3,593,910.95

Certificate Payment Report - Principal
Class	CUSIP	Beginning Principal/Notional Balance	Principal Distribution	Principal Loss	Principal Reimbursed	Subsequent Recoveries	Deferred Interest	Total Principal Distribution	Ending Principal/Notional Balance
A1	93936FAA8	$240,185,272.54	$448,008.09	$0.00	$0.00	$0.00	$0.00	$448,008.09	$239,737,264.45
A2	93936FAB6	$82,573,402.96	$296,273.13	$0.00	$0.00	$0.00	$0.00	$296,273.13	$82,277,129.83
A3	93936FAC4	$42,693,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$42,693,000.00
A4	93936FAD2	$33,571,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$33,571,000.00
A5	93936FAS9	$58,356,374.57	$108,849.84	$0.00	$0.00	$0.00	$0.00	$108,849.84	$58,247,524.73
M1	93936FAE0	$8,307,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$8,307,000.00
M2	93936FAF7	$7,268,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$7,268,000.00
M3	93936FAG5	$4,413,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$4,413,000.00
M4	93936FAH3	$3,894,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$3,894,000.00

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Certificate Payment Report - Principal (Continued)
Class	CUSIP	Beginning Principal/Notional Balance	Principal Distribution	Principal Loss	Principal Reimbursed	Subsequent Recoveries	Deferred Interest	Total Principal Distribution	Ending Principal/Notional Balance
M5	93936FAJ9	$3,634,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$3,634,000.00
M6	93936FAK6	$2,596,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$2,596,000.00
B1	93936FAL4	$2,596,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$2,596,000.00
B2	93936FAM2	$2,596,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$2,596,000.00
B3	93936FAN0	$2,596,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$2,596,000.00
C	93936FAQ3	$5,191,594.93	($0.01)	$0.00	$0.00	$0.00	$0.00	($0.01)	$5,191,594.94
R	93936FAP5	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
PPP	93936FAR1	$500,470,645.93	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$499,617,514.88
R_SYN	XXXXXXXXX	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
TFEE	XXXXXXXXX	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
SWAP_PAYMENT	XXXXXXXXX	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
Total *		$500,470,645.00	$853,131.05	$0.00	$0.00	$0.00	$0.00	$853,131.05	$499,617,513.95

*Total balances exclude notional balances.

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Certificate Payment Report - Interest
Class	Beginning Principal/Notional Balance	Interest Rate Accrued	Interest Rate Paid	Interest Accrued	Prepayment Interest Shortfall	Relief Act Shortfall	Other Interest Shortfall	Unscheduled Interest	Interest Reimbursed	Carryforward Amount Paid	Total Interest Distributed	Total Carryforward Amount Remaining
A1	$240,185,272.54	5.3712500000%	5.3705369624%	$1,075,079.29	$0.00	$142.72	$0.00	($0.08)	$0.00	$0.00	$1,074,936.49	$0.00
A2	$82,573,402.96	5.2512500000%	5.2505528470%	$361,344.65	$0.00	$47.97	$0.00	($0.03)	$0.00	$0.00	$361,296.65	$0.00
A3	$42,693,000.00	5.3612500000%	5.3605382615%	$190,739.87	$0.00	$25.32	$0.00	($0.02)	$0.00	$0.00	$190,714.53	$0.00
A4	$33,571,000.00	5.4512500000%	5.4505264663%	$152,503.26	$0.00	$20.25	$0.00	($0.01)	$0.00	$0.00	$152,483.01	$0.00
A5	$58,356,374.57	5.4512500000%	5.4505263965%	$265,095.99	$0.00	$35.19	$0.00	($0.02)	$0.00	$0.00	$265,060.78	$0.00
M1	$8,307,000.00	5.5812500000%	5.5805084868%	$38,636.20	$0.00	$5.13	$0.00	$0.00	$0.00	$0.00	$38,631.07	$0.00
M2	$7,268,000.00	5.6812500000%	5.6804958723%	$34,409.44	$0.00	$4.57	$0.00	$0.00	$0.00	$0.00	$34,404.87	$0.00
M3	$4,413,000.00	5.8312500000%	5.8304772264%	$21,444.42	$0.00	$2.85	$0.00	$0.00	$0.00	$0.00	$21,441.58	$0.00
M4	$3,894,000.00	6.3812500000%	6.3804036980%	$20,707.16	$0.00	$2.75	$0.00	$0.00	$0.00	$0.00	$20,704.41	$0.00
M5	$3,634,000.00	6.6312500000%	6.6303698404%	$20,081.64	$0.00	$2.67	$0.00	$0.00	$0.00	$0.00	$20,078.97	$0.00
M6	$2,596,000.00	6.6967525364%	6.8803590139%	$14,487.31	$0.00	$1.92	$0.00	$0.00	$0.00	$399.13	$14,884.51	$0.00
B1	$2,596,000.00	6.6967525364%	7.1303620955%	$14,487.31	$0.00	$1.92	$0.00	$0.00	$0.00	$939.96	$15,425.35	$0.00

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Certificate Payment Report - Interest (Continued)
Class	Beginning Principal/Notional Balance	Interest Rate Accrued	Interest Rate Paid	Interest Accrued	Prepayment Interest Shortfall	Relief Act Shortfall	Other Interest Shortfall	Unscheduled Interest	Interest Reimbursed	Carryforward Amount Paid	Total Interest Distributed	Total Carryforward Amount Remaining
B2	$2,596,000.00	6.6967525364%	7.1303620955%	$14,487.31	$0.00	$1.92	$0.00	$0.00	$0.00	$939.96	$15,425.35	$0.00
B3	$2,596,000.00	6.6967525364%	7.1303620955%	$14,487.31	$0.00	$1.92	$0.00	$0.00	$0.00	$939.96	$15,425.35	$0.00
C	$5,191,594.93	0.0000000000%	127.5284140860%	$0.00	$0.00	$0.00	$0.00	($0.04)	$0.00	$0.00	$551,729.85	$0.00
R	$0.00	0.0000000000%	0.0000000000%	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
PPP	$500,470,645.93	0.0000000000%	0.0000000000%	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
R_SYN	$0.00	0.0000000000%	0.0000000000%	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
TFEE	$0.00	0.0000000000%	0.0000000000%	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$500.47	$0.00
SWAP_PAYMENT	$0.00	0.0000000000%	0.0000000000%	$0.00	$51,862.84	$0.00	$0.00	$0.00	$0.00	$0.00	($51,862.84)	$0.00
Total *	$500,470,645.00			$2,237,991.16	$0.00	$297.10	$0.00	($0.22)	$0.00	$3,219.01	$2,792,642.75	$0.00

*Total balances exclude notional balances.

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Principal Factors Report
Class	Original Scheduled Balance	Beginning Principal/Notional Balance	Principal Loss	Principal Reimbursed	Subsequent Recoveries	Deferred Interest	Total Principal	Ending Principal/Notional Balance Percent	Ending Principal/Notional Balance
A1	$250,000,000.00	960.74109016	0.00000000	0.00000000	0.00000000	0.00000000	1.79203236	0.9589490578	958.94905780
A2	$89,064,000.00	927.12434833	0.00000000	0.00000000	0.00000000	0.00000000	3.32651947	0.9237978289	923.79782886
A3	$42,693,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
A4	$33,571,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
A5	$60,741,000.00	960.74109037	0.00000000	0.00000000	0.00000000	0.00000000	1.79203240	0.9589490580	958.94905797
M1	$8,307,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
M2	$7,268,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
M3	$4,413,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
M4	$3,894,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
M5	$3,634,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
M6	$2,596,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Principal Factors Report (Continued)
Class	Original Scheduled Balance	Beginning Principal/Notional Balance	Principal Loss	Principal Reimbursed	Subsequent Recoveries	Deferred Interest	Total Principal	Ending Principal/Notional Balance Percent	Ending Principal/Notional Balance
B1	$2,596,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
B2	$2,596,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
B3	$2,596,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
C	$5,190,486.00	1,000.21364666	0.00000000	0.00000000	0.00000000	0.00000000	-0.00000193	1.0002136486	1,000.21364859
R	$100.00	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.0000000000	0.00000000
PPP	$0.00	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.0000000000	0.00000000
R_SYN	$0.00	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.0000000000	0.00000000
TFEE	$0.00	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.0000000000	0.00000000
SWAP_PAYMENT	$0.00	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.0000000000	0.00000000

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Interest Factors Report
Class	Original Balance	Interest Rate Accrued	Interest Rate Paid	Current Month Interest Accrued	Prepayment Interest Shortfall	Relief Act Interest Shortfall	Other Interest Shortfall	Unscheduled Interest	Interest Reimbursed	Carryforward Amount Paid	Deferred Interest	Total Interest Distribution	Total Carryforward Amount Remaining
A1	$250,000,000.00	5.3712500000%	5.3705369624%	4.30031716	0.00000000	0.00057088	0.00000000	-0.00000032	0.00000000	0.00000000	0.00000000	4.29974596	0.00000000
A2	$89,064,000.00	5.2512500000%	5.2505528470%	4.05713476	0.00000000	0.00053860	0.00000000	-0.00000034	0.00000000	0.00000000	0.00000000	4.05659582	0.00000000
A3	$42,693,000.00	5.3612500000%	5.3605382615%	4.46770829	0.00000000	0.00059307	0.00000000	-0.00000047	0.00000000	0.00000000	0.00000000	4.46711475	0.00000000
A4	$33,571,000.00	5.4512500000%	5.4505264663%	4.54270829	0.00000000	0.00060320	0.00000000	-0.00000030	0.00000000	0.00000000	0.00000000	4.54210509	0.00000000
A5	$60,741,000.00	5.4512500000%	5.4505263965%	4.36436657	0.00000000	0.00057935	0.00000000	-0.00000033	0.00000000	0.00000000	0.00000000	4.36378690	0.00000000
M1	$8,307,000.00	5.5812500000%	5.5805084868%	4.65104129	0.00000000	0.00061755	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	4.65042374	0.00000000
M2	$7,268,000.00	5.6812500000%	5.6804958723%	4.73437534	0.00000000	0.00062878	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	4.73374656	0.00000000
M3	$4,413,000.00	5.8312500000%	5.8304772264%	4.85937458	0.00000000	0.00064582	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	4.85873102	0.00000000
M4	$3,894,000.00	6.3812500000%	6.3804036980%	5.31770930	0.00000000	0.00070621	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	5.31700308	0.00000000
M5	$3,634,000.00	6.6312500000%	6.6303698404%	5.52604293	0.00000000	0.00073473	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	5.52530820	0.00000000
M6	$2,596,000.00	6.6967525364%	6.8803590139%	5.58062789	0.00000000	0.00073960	0.00000000	0.00000000	0.00000000	0.15374807	0.00000000	5.73363251	0.00000000

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Interest Factors Report (Continued)
Class	Original Balance	Interest Rate Accrued	Interest Rate Paid	Current Month Interest Accrued	Prepayment Interest Shortfall	Relief Act Interest Shortfall	Other Interest Shortfall	Unscheduled Interest	Interest Reimbursed	Carryforward Amount Paid	Deferred Interest	Total Interest Distribution	Total Carryforward Amount Remaining
B1	$2,596,000.00	6.6967525364%	7.1303620955%	5.58062789	0.00000000	0.00073960	0.00000000	0.00000000	0.00000000	0.36208012	0.00000000	5.94196841	0.00000000
B2	$2,596,000.00	6.6967525364%	7.1303620955%	5.58062789	0.00000000	0.00073960	0.00000000	0.00000000	0.00000000	0.36208012	0.00000000	5.94196841	0.00000000
B3	$2,596,000.00	6.6967525364%	7.1303620955%	5.58062789	0.00000000	0.00073960	0.00000000	0.00000000	0.00000000	0.36208012	0.00000000	5.94196841	0.00000000
C	$5,190,486.00	0.0000000000%	127.5284140860%	0.00000000	0.00000000	0.00000000	0.00000000	-0.00000771	0.00000000	0.00000000	0.00000000	106.29637572	0.00000000
R	$100.00	0.0000000000%	0.0000000000%	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000
PPP	$0.00	0.0000000000%	0.0000000000%	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000
R_SYN	$0.00	0.0000000000%	0.0000000000%	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000
TFEE	$0.00	0.0000000000%	0.0000000000%	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000
SWAP_PAYMENT	$0.00	0.0000000000%	0.0000000000%	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Collateral Report Pool 8108
LOAN COUNT
Original Loan Count	1765
Beginning Loan Count	1705
Loans Added	0
Loans Prepaid-in-full	3
Loans Liquidated-in-full	0
Loans Repurchased	0
Ending Loan Count	1702
PRINCIPAL BALANCE
Original Scheduled Principal Balance	$519,159,586.94
Beginning Scheduled Principal Balance	$500,470,645.93
Scheduled Principal Received or Advanced	$96,096.43
Unscheduled Principal	$42,765.85
Prepayments-in-full	$714,268.77

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Collateral Report Pool 8108 (Continued)
PRINCIPAL BALANCE
Liquidations-in-full	$0.00
Repurchases	$0.00
Principal Losses	$0.00
Ending Scheduled Principal Balance	$499,617,514.88
INTEREST
Accrued Interest at Gross Rate	$2,904,322.66
Unscheduled Interest	($0.22)
Uncollected Interest	($617.17)
Relief Act Shortfall	$297.10
Prepayment Interest Shortfall	$0.00
Other Interest Shortfall	$0.00

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Collateral Report Pool 8108 (Continued)
FEES
Servicing Fees	$163,245.44
Other Fees	$0.00
ADDITIONAL FUNDS
Excess Liquidation Proceeds	$0.00
Subsequent Recoveries	$0.00
Prepayment Penalties	$0.00
Other	$0.00

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Collateral Report Total
LOAN COUNT
Original Loan Count	1765
Beginning Loan Count	1705
Loans Added	0
Loans Prepaid-in-full	3
Loans Liquidated-in-full	0
Loans Repurchased	0
Ending Loan Count	1702
PRINCIPAL BALANCE
Original Scheduled Principal Balance	$519,159,586.94
Beginning Scheduled Principal Balance	$500,470,645.93
Scheduled Principal Received or Advanced	$96,096.43
Unscheduled Principal	$42,765.85
Prepayments-in-full	$714,268.77

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Collateral Report Total (Continued)
PRINCIPAL BALANCE
Liquidations-in-full	$0.00
Repurchases	$0.00
Principal Losses	$0.00
Ending Scheduled Principal Balance	$499,617,514.88
INTEREST
Accrued Interest at Gross Rate	$2,904,322.66
Unscheduled Interest	($0.22)
Uncollected Interest	($617.17)
Relief Act Shortfall	$297.10
Prepayment Interest Shortfall	$0.00
Other Interest Shortfall	$0.00

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Collateral Report Total (Continued)
FEES
Servicing Fees	$163,245.44
Other Fees	$0.00
ADDITIONAL FUNDS
Excess Liquidation Proceeds	$0.00
Subsequent Recoveries	$0.00
Prepayment Penalties	$0.00
Other	$0.00

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Delinquency Information by Group*
Group ID	1 Month Count	Scheduled Ending Balance	2 Months Count	Scheduled Ending Balance	3 Months Count	Scheduled Ending Balance	4+ Months Count	Scheduled Ending Balance
Pool 8108	124	$43,000,917.33	47	$16,276,619.19	27	$10,206,780.76	31	$7,138,951.29
Aggregate	124	$43,000,917.33	47	$16,276,619.19	27	$10,206,780.76	31	$7,138,951.29

* Does not include mortgage loans in foreclosure or REO.

Foreclosure, REO, and Bankruptcy by Group**
Group ID	Foreclosure Count	Scheduled Ending Balance	REO Count	Scheduled Ending Balance	Bankruptcy Count	Scheduled Ending Balance
Pool 8108	63	$23,984,120.30	0	$0.00	2	$472,000.00
Aggregate	63	$23,984,120.30	0	$0.00	2	$472,000.00

** Loans in Bankruptcy will also be reflected under their applicable delinquency or foreclosure status.

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Aggregate Loss Amount by Group
Group ID	Count	Loss Amount
Pool 8108	0	$0.00
Aggregate	0	$0.00

Servicer Advances by Group
Group	Count	Total
Pool 8108	1549	$4,089,636.72
Aggregate	1549	$4,089,636.72

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Stop Advances Loans
Group	Count	Loan Balance	Total Scheduled P&I
Pool 8108	0	$0.00	$0.00
Aggregate	0	$0.00	$0.00

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Delinquency Roll Rates-Aggregate***
Current Value	Current		1 Month		2 Months		3 Months
Prior Value	Count	Balance	Count	Balance	Count	Balance	Count	Balance
Current	1375	$388,923,433.17	97	$33,291,547.37	4	$1,056,498.23	1	$246,079.24
Delq 1 Month	25	$7,607,536.91	25	$8,226,970.60	39	$13,997,412.93	0	$0.00
Delq 2 Month	5	$1,372,197.44	0	$0.00	3	$1,039,591.53	26	$9,960,701.52
Delq 3 Month	1	$171,464.61	1	$282,399.36	0	$0.00	0	$0.00
Delq 4 Month	4	$935,493.88	1	$1,200,000.00	1	$183,116.50	0	$0.00
Foreclosure	0	$0.00	0	$0.00	0	$0.00	0	$0.00

Current Value	4+ Months		Foreclosure		REO
Prior Value	Count	Balance	Count	Balance	Count	Balance
Current	27	$5,775,924.13	0	$0.00	0	$0.00
Delq 1 Month	1	$198,414.87	0	$0.00	0	$0.00
Delq 2 Month	0	$0.00	1	$574,822.58	0	$0.00
Delq 3 Month	3	$1,164,612.29	25	$7,557,510.19	0	$0.00
Delq 4 Month	0	$0.00	0	$0.00	0	$0.00
Foreclosure	0	$0.00	37	$15,851,787.53	0	$0.00

*** To use this chart, locate along the Current Value row the desired delinquency status as of the immediately preceding due date (e.g. Current, 1 Month delinquent, etc.). Use the left hand column labeled Prior Value to see the prior month's value. Follow the selected Current Value column to the desired Prior Value row.

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Credit Enhancement
Type	Original Balance	Beginning Balance	Reduction	Increase	Ending Balance
Over Collateralization	$5,190,486.00	$5,191,594.93	$0.00	$0.01	$5,191,594.94
Swap Counterparty Inflow	$0.00	$869,357.27	$0.00	$51,862.84	$921,220.11
Reserve Account	$0.00	$0.00	$0.00	$0.00	$0.00
Other	$0.00	$0.00	$0.00	$0.00	$0.00

Insurance
Insurance Type	Original Balance	Claims Paid	Coverage Remaining
Pool Insurance	$0.00	$0.00	$0.00
Other	$0.00	$0.00	$0.00

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Subordinate Class Certificate Balances
The Class Principal Balances of each Class of the Class M1,M2,M3,M4,M5,M6,B1,B2,B3,C Certificates immediately after the principal and interest distribution on 10/25/2007 are as follows:
Class	Ending Principal Balance	Percentage of Aggregate Certificate Principal Balance on Closing Date	Percentage of Aggregate Certificate Ending Principal Balance
M1	$8,307,000.00	1.60%	1.66%
M2	$7,268,000.00	1.40%	1.45%
M3	$4,413,000.00	0.85%	0.88%
M4	$3,894,000.00	0.75%	0.78%
M5	$3,634,000.00	0.70%	0.73%
M6	$2,596,000.00	0.50%	0.52%
B1	$2,596,000.00	0.50%	0.52%
B2	$2,596,000.00	0.50%	0.52%
B3	$2,596,000.00	0.50%	0.52%
C	$5,191,594.94	1.00%	1.04%
Total	$43,091,594.94	8.30%	8.62%

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Glossary of Terms
TERM	DEFINITION
Average Ending Scheduled Principal Balance	Average scheduled principal balance of all mortgage loans as of the immediately preceding due date.
Compensating Interest	Interest paid by the servicer or master servicer in respect of Prepayment Interest Shortfall, subject to specified caps.
CPR (Constant Prepayment Rate)	The annualized, compounded single month mortality rate.
Current Interest Accrued	The interest accrued for the current month's distribution.
Deferred Interest	When a scheduled monthly payment is less than required to satisfy the note rate, the unpaid interest is deferred by adding it to the loan balance and the certificate balances.
Excess Liquidation Proceeds	Funds received at the time of liquidation in excess of the amount needed to satisfy the outstanding scheduled principal balance and related expenses.
Interest Rate Accrued	The rate at which interest is accrued for the current month's distribution.
Interest Rate Paid	The rate at which interest is paid for the current month's distribution.
Uncollected Interest	Interest not collected on delinquent loans for which scheduled payments are no longer being advanced, interest uncollected on prepayments and interest uncollected on liquidations.
Other Interest Shortfall	Any interest shortfall other than Uncompensated Interest Shortfall, Deferred Interest or Interest Uncollected on Non-Earning Assets.
Over Collateralization	Any excess of the aggregate principal balance of the mortgage loans over the aggregate principal balance of the certificates.
Prefunding Amount	The amount of cash being held for future loan purchases.

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Glossary of Terms (Continued)
TERM	DEFINITION
Prepayment Interest Shortfall	Any shortfall in collections of interest on mortgage loans resulting from prepayments in full or partial prepayments.
Principal Loss	The amount of principal reduction due to a loss realized on the mortgage loans.
Principal Reimbursed	The amount of principal passed through as a reimbursement.
PSA (Prepayment Speed Assumption)	A prepayment model that in its base case (stated as 100% PSA), assumes that prepayments start in month one at an annual CPR of 0.2%, rising linearly to 6.0% CPR in month 30, and then remain flat at 6.0% CPR thereafter.
Relief Act Shortfall	Interest shortfall resulting from application of the Servicemembers Civil Relief Act.
REO (Real Estate Owned)	Property acquired by the trust through foreclosure or deed-in-lieu of foreclosure on a defaulted loan.
Reserve Account	Funded or non-funded accounts set up at either the property or portfolio level in in anticipation of periodic or non-periodic capital expenditures or cash needs.
Servicer Advances	Scheduled principal and interest advances made by the servicer or master servicer for delinquent mortgage loans.
Servicing Fees	The monthly fee paid to the servicer to perform primary servicing function for the master servicer with respect to the mortgage loans and if applicable the fee charged by the master servicer for supervising the mortgage loan servicing.
SMM (Single Month Mortality)	In any given month, the SMM measures the percentage of the beginning pool balance that was paid back earlier than scheduled through payoffs.
Stop Advance	The amount of principal and interest on delinquent mortgage loans for which scheduled payments are no longer being advanced.
Subsequent Recoveries	The amount of funds recovered on mortgage loans that were previously liquidated at a loss.
Trigger Event	An event that may require a change in payment priority.

Series: WMALT 2007-OC1	Washington Mutual
Issue Date: 05/11/2007
Record Date: 09/28/2007
Distribution Date: 10/25/2007

Glossary of Terms (Continued)
TERM	DEFINITION
Unscheduled Interest	Interested collected in addition to the scheduled interest payment.
Unscheduled Principal	Payments of principal which were received with respect to any mortgage loan during the prior period, other than monthly scheduled principal, prepayments in full, repurchases, liquidation principal and subsequent recoveries.
Weighted Average Loan Age	For any distribution date, the weighted average of the loan age on the mortgage loans as of the immediately preceding due date.
Weighted Average Mortgage Interest Rate	For any distribution date, the weighted average of the mortgage interest rates on the mortgage loans as of the second preceding due date (after giving effect to the payments due on the mortgage loans on that due date).
Weighted Average Pass Through Rate	For any distribution date, the weighted average of the pass-through rates on the mortgage loans as of the second preceding due date (after giving effect to the payments due on the mortgage loans on that due date).
Weighted Average Remaining Term	For any distribution date, the weighted average of the maturity on the mortgage loans as of the immediately preceding due date.
MBA Delinquency Calculation	In this calculation, a loan increases its delinquency status if a monthly payment is not received by the end of the day immediately preceding the loan's next due date.
OTS Delinquency Calculation	In this calculation, a loan increases its delinquency status if a monthly payment is not received by the loan's due date in the following month.

Washington Mutual Mortgage Pass-Through Certificates, WMALT Series 2007-OCI 10-D