CMALT 2007-A4 SENIOR UNDERWRITING AGREEMENT

EXHIBIT 4.1

Citicorp Mortgage Securities, Inc.

Depositor

CitiMortgage, Inc.

Servicer and Master Servicer

U.S. Bank National Association

Trustee

Citibank, N.A.

Paying Agent, Certificate Registrar

and Authenticating Agent

Pooling and Servicing Agreement

CMALT (CitiMortgage Alternative Loan Trust), Series 2007-A4

REMIC Pass-Through Certificates

April 1, 2007

Contents

PARTIES 9

BACKGROUND 9

AGREEMENT 9

SERIES TERMS 9

2

STANDARD TERMS 35

1   Definitions and usages 35

1.1   Defined terms 35

1.2   Usages 51

1.3   Calculations respecting mortgage loans 51

2   Transfer of mortgage loans and issuance of certificates; repurchase and substitution 52

2.1   Transfer of mortgage loans 52

2.2   CMSI’s representations and warranties 56

2.3   Repurchase or substitution of mortgage loans 58

3   Servicing 60

3.1   CitiMortgage as servicer and master servicer 60

3.2   Collections 61

3.3   Certificate and other accounts 62

3.4   Prepayment interest shortfalls 64

3.5   Advances 65

3.6   Distributions 67

3.7   Third-party servicing 69

3.8   Permitted withdrawals from certificate account 70

3.9   Expenses 72

3.10   Primary mortgage insurance 72

3.11   Hazard insurance 72

3.12   Realization on defaulted mortgage loans 73

3.13   Release of mortgage files 75

3.14   Reports to certificate holders and others 76

3.15   Tax returns and reports 78

3.16   Application of buydown funds 78

3.17   Assumption and modification agreements 79

3.18   Refinancings and curtailments; loan modifications 80

3.19   Investment accounts 81

3.20   Paying Agent and Certificate Registrar 84

3.21   Exchange Act reporting 84

4   CitiMortgage 85

4.1   Liability of CitiMortgage and others 85

4.2   Assumption of CitiMortgage’s obligations by affiliate 86

4.3   Maintenance of office or agency 86

4.4   Servicer not to resign 87

4.5   Delegation of duties 87

4.6   Errors and omissions insurance 87

5   The certificates 87

5.1   The certificates 87

5.2   Registration of transfer and exchange of certificates 89

5.3   Mutilated, destroyed, lost or stolen certificates 92

5.4   Persons deemed owners 93

5.5   Access to list of certificate holders’ names and addresses 93

5.6   Definitive certificates 93

5.7   Notices to Clearing Agency 94

6   [Reserved] 94

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7   Default 94

7.1   Events of Default 94

7.2   Trustee to act; appointment of successor 95

8   The Trustee 95

8.1   Duties 95

8.2   Liability 97

8.3   Trustee not liable for certificates or mortgage loans 97

8.4   Trustee may own certificates 98

8.5   Trustee’s fees and expenses 98

8.6   Eligibility requirements for Trustee 99

8.7   Resignation or removal of Trustee 99

8.8   Successor trustee 100

8.9   Merger or consolidation of Trustee 100

8.10   Appointment of co-trustee or separate trustee 100

8.11   Tax returns 102

8.12   Appointment of authenticating agent 102

9   Termination 103

9.1   Termination upon repurchase by CMSI or liquidation of all mortgage loans 103

10   General provisions 105

10.1   Amendments 105

10.2   Recordation of Agreement 106

10.3   Limitation on rights of certificate holders 106

10.4   Governing law 107

10.5   Maintenance of REMICs 107

10.6   Notices 107

10.7   Severability of provisions 107

10.8   Assignment 108

10.9   Certificates nonassessable and fully paid 108

11   Depositories 108

11.1   Depositories 108

SIGNATURES AND ACKNOWLEDGMENTS 110

Schedule 1: Servicing criteria to be addressed in report on assessment of compliance

Appendix 1: Transferee’s Affidavit

Exhibit A: Forms of certificates A-1

Exhibit B: Mortgage Loan Schedules

Exhibit C: Form of Mortgage Document Custodial Agreement C-1

Exhibit D: Form of Purchaser Letter D-1

Exhibit E: Form of ERISA Letter E-1

Exhibit F: Form of Yield Maintenance Agreement F-1

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Defined Terms

accrual class, 17

accrual directed class, 17

accrual termination day, 35

advance account, 27

advance account advances, 27

advance account available advance amount, 27

advance account depository, 27

advance account depository agreement, 27

advance account funding date, 27

advance account trigger date, 27

affiliate, 35

affiliated mortgage loans, 60

affiliated Paying Agent advances, 66

affiliated servicing fee rate, 35

Agent, 89

aggregate outstanding advances, 35

allocated loss, 20

alternative certificate account, 108

alternative custodial accounts for P&I, 108

alternative escrow account, 108

alternative servicing account, 108

APPLICABLE CONSTITUENT REMIC, 28

appraisal, 35

assumed principal balance, 32

Authenticating Agent, 9, 102

Authorized Officer, 35

Bankruptcy Code, 35

bankruptcy coverage termination date, 35

bankruptcy loss, 35

bankruptcy loss limit, 35

beneficial owner, 36

book-entry certificates, 13

business day, 36

buydown account, 36

buydown funds, 36

buydown mortgage loan, 36

buydown subsidy agreement, 36

certificate account, 62

certificate holder, 36

certificate insurance policy, 27

certificate rate, 10

Certificate Register, 89

Certificate Registrar, 10

certificates, 9

Citibank banking affiliate, 36

CitiMortgage, 9

class, 36

class A-PO, 9

class A-PO certificates, 9

class B holder, 60

class B-x, 9

class B- x certificates, 9

class IA-IO, 9

class IA-IO certificates, 9

class IA-x, 9

class IA- x certificates, 9

class IIA-1, 9

class IIA- 1 certificates, 9

class IIA-IO, 9

class IIA-IO certificates, 9

class L regular interest, 28

class LR certificates, 9

class P regular interests, 28

class percentage, 36

class PR certificates, 9

class R certificates, 9

classes A- x through A- y , 37

classes B- x through B- y , 37

Clearing Agency, 37

Clearing Agency Participant, 37

closing date, 10

CMSI, 9

collected servicing fee, 37

component classes, 22

composite class, 22

constituent REMIC, 27

corporate trust office, 34

cumulative loss test, 15

current interest allocation, 14

custodial accounts for P&I, 63

custodial investment account, 82

cut-off date, 9

debt service reduction, 37

deficient valuation, 37

definitive certificates, 13

delegated servicer, 37

delinquency test, 15

denominations, 12

Depository, 38

determination date, 38

discount loan, 38

disqualified organization, 89

5

distribution account, 67

distribution day, 10

distribution day data, 68

distribution day statement, 69

distribution report, 76

Eligible Account, 38

Eligible Investments, 82

eligible substitute mortgage loan, 59

ERISA, 38

ERISA Prohibited holder, 89

ERISA Restricted Certificates, 38

escrow accounts, 63

Events of Default, 94

Exchange Act, 38

extraordinary event, 38

FDIC, 38

Fitch, 38

fraud loss, 39

fraud loss limit, 38

Furnished Document, 96

GIC, 39

GNMA, 39

group, 22, 39

group target-rate class percentage, 39

Guide, 39

high-cost mortgage loan, 39

holder, 39

hypothetical mortgage loan, 39

impaired subordination level, 15

independent accountants, 39

Indirect Participant, 39

initial, 39

initial bankruptcy loss limit, 12

initial fraud loss amount, 12

initial special hazard loss limit, 12

insurance premium, 27

insurance proceeds, 39

insured class, 27

Insurer, 27

interest allocation, 14

interest allocation carryforward, 14

interest distribution, 17

interest portion of a liquidated loan loss, 40

interest portion of a realized loss, 47

Internal Revenue Code, 40

investment account, 40

Investment Income, 40

IO class, 40

IO loan, 40

IO strip, 40

last scheduled distribution day, 10

latest possible maturity date, 10

LIBOR, 21

LIBOR accrual period, 21

LIBOR classes, 21

liquidated loan, 40

liquidated loan loss, 40

liquidation expenses, 40

liquidation proceeds, 40

loss recovery, 41

LOWER-TIER REMIC, 27

lower-tier REMIC account, 30

margin, 32

master servicer, 60

master servicing fee, 41

master servicing fee rate, 41

material breach, 58

maximum protection percentage, 32

MERS, 53

month, 41

monthly affiliated servicing fee rate, 35

monthly master servicing fee rate, 41

monthly pass-through rate, 44

monthly third-party servicing fee rate, 50

Moody’s, 41

Morgan Stanley, 10

mortgage, 41

Mortgage Document Custodial Agreement, 52

Mortgage Document Custodian, 52

mortgage documents, 41

mortgage file, 41

mortgage loan, 41

mortgage loan schedule, 41

mortgage note, 41

Mortgage Note Custodian, 41

mortgage note rate, 41

mortgaged property, 41

mortgagor, 41

multiple-pool series, 41

NAS classes, 17

net liquidation proceeds, 41

net Paying Agent advances, 42

net REO proceeds, 42

net voluntary advances, 42

non-accelerated senior classes, 17

nonrecoverable advance, 42

non-subordinated losses, 42

non-supported prepayment interest shortfall, 42

notional balance, 13

officer’s certificate, 42

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opinion of counsel, 42

order of seniority, 42

order of subordination, 42

original value, 43

Originator, 43

outstanding, 43

overcollateralized, 25

PAC class, 17

Participant, 44

pass-through rate, 44

Paying Agent, 10

Paying Agent failure, 27

Paying Agent failure advance, 27

percentage interest, 44

person, 44

planned amortization class, 17

PO class, 44

PO loan, 44

PO strip, 44

pool, 44

pool distribution amount, 45

pool I, 22

pool II, 22

POOLING REMIC, 27

pooling REMIC account, 30

predatory lending law, 45

Predecessor Certificates, 45

premium loan, 45

prepayment interest shortfall, 45

primary mortgage insurance certificate, 45

principal allocation, 14

principal balance, 13

principal distribution, 17

principal portion of a liquidated loan loss, 40

principal portion of a realized loss, 47

principal prepayment, 45

private certificates, 45

Proceeding, 45

property protection expenses, 45

Purchaser, 10

Qualified GIC, 45

Qualified Nominee, 46

rating agency, 10

ratio-stripped IO class, 47

ratio-stripped IO loan, 47

ratio-stripped PO class, 47

ratio-stripped PO loan, 47

realized losses, 47

record date, 47

reduction amount, 25

regular interests, 28

Regulation AB, 85

reimbursement, 17

relevant servicer, 47

Relieved interest, 66

REMIC, 47

REMIC Provisions, 47

remittance delinquency, 65

remittances on affiliated mortgage loans, 62

remittances on third-party loans, 64

REO loan, 47

REO proceeds, 47

REO property, 47

Required Amount of Certificates, 47

reserve fund, 27

residual certificates, 9

residual distribution, 17

residual interest, 28

Responsible Officer, 48

retail class, 27

retail reserve fund, 27

S&P, 48

scheduled monthly loan payment, 48

scheduled principal balance, 48

scheduled principal payments, 48

scheduled servicing fee, 48

Securities Act, 48

senior classes, 9

senior to, 48

Series Terms, 9

servicing account advances, 65

servicing accounts, 63

Servicing Officer, 48

Similar Law, 92

single certificate, 48

single-pool series, 48

special hazard loss, 48

special hazard loss limit, 49

special hazard percentage, 49

special servicer, 60

special servicing agreement, 60

specially serviced mortgage loans, 60

Standard Terms, 9

startup day, 10

subordinate to, 49

subordinated classes, 9

subordinated losses, 49

subordination depletion date, 49

subordination level, 15

substitution adjustment amount, 59

7

substitution day, 59

super senior classes, 27

super senior support classes, 27

TAC class, 17

target rate, 12

targeted amortization class, 17

target-rate class, 12

target-rate class percentage, 49

target-rate loan, 49

target-rate strip, 49

tax matters person, 31

third-party mortgage loans, 60

third-party Paying Agent advance, 66

third-party servicer, 60

third-party servicer advance, 65

third-party servicing agreement, 60

third-party servicing fee, 50

third-party servicing fee rate, 50

Transfer Instrument, 50

Trust, 9

Trust Fund, 50

Trustee, 9

U.S. person, 50

uncommitted cash, 50

uncommitted cash advances, 65

undercollateralized, 25

undersubordination, 25

Underwriter, 10

unscheduled principal payments, 50

UPPER-TIER REMIC, 28

upper-tier REMIC account, 30

voluntary advance, 65

voting interest, 13

yield maintenance agreement, 32

yield maintenance amount, 33

yield maintenance payments, 32

yield maintenance percentage, 32

yield maintenance provider, 32

yield maintenance reserve fund, 33

yield protected certificates, 32

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POOLING AND SERVICING AGREEMENT

April 1, 2007

PARTIES

BACKGROUND

In the regular course of their business, affiliates of CMSI originate and acquire mortgage loans. CMSI, CitiMortgage and the Trustee wish to set forth the terms and conditions under which the Trust will acquire the mortgage loans listed in exhibit B, certificates will be issued to holders evidencing ownership interests in the Trust Fund, and CitiMortgage will manage and service the mortgage loans.

AGREEMENT

This Pooling and Servicing Agreement (this agreement ) consists of sections 1 through 11 (the Standard Terms ) and sections 12 and following (the Series Terms ). The Standard Terms follow the Series Terms. If there is a conflict or inconsistency between the Standard Terms and the Series Terms, the Series Terms will prevail.

SERIES TERMS

12.1   Establishment

A common law trust is established under New York law as of April 1, 2007 (the cut-off date ), to be called the "CMALT (CitiMortgage Alternative Loan Trust), Series 2007-A4" (the Trust ). CMSI is the settlor of the Trust, and U.S. Bank National Association is the trustee (in such capacity, the Trustee ).

The Trust will issue a series of certificates designated as "CMALT (CitiMortgage Alternative Loan Trust), Series 2007-A4 REMIC Pass-Through Certificates." The certificates will consist of and be further designated as

(i)   20 senior classes of certificates individually designated as

·   for each integer x , from 1 through 16, inclusive, "Senior Class IA- x Certificates" (the class IA-x certificates or class IA-x );

·   "Senior Class IIA-1 Certificates" (the class IIA-1 certificates or class IIA-1 );

·   "Senior Class IA-IO Certificates" (the class IA-IO certificates or class IA-IO );

·   "Senior Class IIA-IO Certificates" (the class IIA-IO certificates or class IIA-IO ); and

·   "Senior Class A-PO Certificates" (the class A-PO certificates or class A-PO ).

(ii)   six subordinated classes of certificates designated, for each integer x , from 1 through 6, inclusive, as "Subordinated Class B- x Certificates" (the class B-x certificates or class B-x ) (together with the senior classes of certificates, the certificates ); and

(iii)   three residual interests individually designated as

·   "Class PR Certificates" (the class PR certificates ),

·   "Class LR Certificates" (the class LR certificates ), and

·   "Class R Certificates" (the class R certificates ).

The class PR, LR and R certificates together constitute the residual certificates .

The Trustee hereby appoints Citibank, N.A. as Authenticating Agent .

CMSI, with the approval of the Trustee, hereby appoints the corporate trust

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department of Citibank, N.A. as Paying Agent and Certificate   Registrar .

The Mortgage Document Custodian is Citibank, N.A.

The Underwriters for the series are Morgan Stanley & Co. Incorporated ( Morgan Stanley ) and Greenwich Capital Markets, Inc., and the Purchaser is Greenwich Capital Markets, Inc.

The certificates will be first executed, authenticated and delivered on April 26, 2007 (the closing date ). The closing date will also be the startup day .

The 25th day of each month (or if the 25th is not a business day, the next succeeding business day), beginning in May 2007, will be a distribution day . The last scheduled distribution day for each class is specified in the following table. The latest possible maturity date of each class for purposes of section 860G(a)(1) of the Internal Revenue Code and Treasury Regulations section 1.860G-1(a)(4)(iii) will be April 25, 2037.

The nationally recognized statistical rating agencies for the senior classes are Moody’s and Fitch, and for classes IA-9 and IA-13 through IA-16 only, S&P; the rating agency for classes B-1 through B-5 is Fitch.

12.2   General terms for classes

The classes will have the following initial principal balances, certificate rates , and for the subordinated classes, initial target-rate class percentages and initial subordination levels:

10

____________

11

12.3   Target rate

The annual target rates for the pools are

pool I:   6%

pool II:   5.5%

Each class other than any ratio-stripped IO or ratio-stripped PO class is a target-rate class .

12.4   Ratio-stripped IO and PO classes

Each of classes IA-IO and IIA-IO is a ratio-stripped IO class, and class A-PO is a ratio-stripped PO class.

12.5   Loss limits

There is no initial special hazard loss limit , initial bankruptcy loss limit , or initial fraud loss amount .

12.6   Denominations

The denominations of

·   the senior class certificates and the class B-1 through B-3 certificates are initial principal (or, for any IO classes, notional) balances of $1,000 and any whole dollar amount above $1,000,

·   the class B-4, B-5 and B-6 certificates are $100,000 initial principal balance and any larger integral multiple of $1,000, and

·   the residual certificates are percentage interests summing to 100%.

If the initial principal or notional balance of a class is not a permitted denomination for a certificate of that class, one certificate of the class may be issued in a different denomination.

12.7   The mortgage loans

The mortgage loans in the Trust Fund are identified on the mortgage loan schedule. The mortgage loans in

·   pool I will consist primarily of 15- to 30-year fixed-rate conventional one- to four-family mortgage loans, and

·   pool II will consist primarily of 10- to 15-year fixed-rate conventional one- to four-family mortgage loans.

12.8   Right to repurchase

CMSI cannot exercise its right to repurchase the mortgage loans pursuant to section 9.1(a) of the Standard Terms unless

·   the aggregate scheduled principal balance of the mortgage loans is less than $63,312,732.23 at the time of repurchase, and

·   if there is an insured class outstanding and the exercise of such repurchase right would result in a draw under any certificate insurance policy, the Insurer has previously consented.

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12.9   Book-entry and definitive certificates

All senior class certificates (other than the ratio-stripped IO certificates) and the class B-1 through B-3 certificates will be issued as book-entry certificates . Book-entry certificates for a class or a group of classes will be represented by one or more certificates issued in the name of a depository. The ratio-stripped IO certificates, the class B-4 through B-6 certificates, and the residual certificates will be issued in fully registered certificated form ( definitive certificates ).

12.10   Voting interests 

Each IO class will have a 1% voting interest . The remaining voting interest will be allocated to the other classes in proportion to their principal balances. The voting interest of any class will be allocated among the certificates of the class in proportion to the certificates’ principal or notional balances, except that an Insurer will be entitled to the voting interest of an insured class for as long as the insured class is outstanding and the Insurer is not in default..

12.11   Cash deposit

No cash will be deposited into the certificate account on the closing date.

13.1   Class balances

Each class that is not an IO class will have a principal balance , and each IO class will have a notional balance . The principal or notional balance of multiple classes ( e.g. , the senior classes) is the aggregate of the principal or notional balances of those classes.

The initial principal or notional balance for each class is stated in "The series - General terms for classes" above. The principal balance of each class that is not an IO class will be adjusted on each distribution day, as described in "Adjustments to class balances" below.

The notional balance of a ratio-stripped IO class for any distribution day after the initial distribution day will equal the aggregate scheduled principal balance of the premium loans of the related pool on the last day of the preceding month.

The notional balance of each IO class that is not a ratio-stripped IO class will be adjusted on each distribution day as described in "The series - General terms for classes" above.

13.2   Certificate balances

The sum of the initial principal or notional balances stated on the certificates of each class will equal the initial principal or notional balance of the class.

Except as may be provided in "Retail classes" below, the principal or notional balance of each certificate will equal its proportionate share, based on the initial principal or notional balances stated on the certificates of the class, of the principal balance or notional balance of the class to which the certificate belongs.

14.1   Interest allocations

Beginning on the cut-off date, each class (other than any PO class) will accrue interest for each month on its principal or notional balance at the certificate rate for the class stated in "The series - General terms for classes" above. In calculating accrued interest,

·   a class’s principal or notional balance on the last day of a month will be considered to be the class’s principal or notional balance on every day of the month, and

·   interest for a month will be calculated at 1/12 of the certificate rate, regardless of the number of days in the month.

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Example: Suppose that on January 1, a class has a principal balance of $1,020,000 and a certificate rate of 6% per annum. On the January distribution day, the class’s principal balance is reduced by $20,000. As a result, the principal balance of the class on January 31 is $1 million. Then the interest accrued for the class during January (which is paid on the February distribution day) is 1/12 of 6% of $1 million = $5,000; that the principal balance of the class was greater than $1 million before the January distribution day, and that January has 31 days, are irrelevant.

A class’s interest allocation for a distribution day is the sum of

·   the class’s current interest allocation for the distribution day, consisting of the class’s accrued interest for the preceding month minus the class’s proportionate share, based on accrued interest, of (1) any non-supported prepayment interest shortfall, and (2) the interest portion of any non-subordinated losses, for the preceding month,

·   plus any excess of the class’s interest allocation for the preceding distribution day over the interest distributed to the class on that preceding distribution day (the interest allocation carryforward from that distribution day). (If the class is an insured class, for purposes of calculating allocations and distributions to the class, the interest allocation carryforward from a distribution day will be reduced by any payments to the class from the Insurer relating to the interest allocation carryforward, but will not be so reduced for purposes of effecting the Insurer’s subrogation rights relative to the interest portion of any insured payment.)

14.2   Principal allocations

The principal allocation for a distribution day is:

(a) for any ratio-stripped PO class, the sum for that distribution day of scheduled and unscheduled principal payments on its PO strip for that distribution day.

(b) for the senior target-rate classes collectively,   the sum   for that distribution day   of

·   the target-rate class percentage for the senior target-rate classes of scheduled principal payments on the target-rate strip, and

·   all unscheduled principal payments on the target-rate strip allocated to the senior target-rate classes pursuant to " - Unscheduled principal" below.

The principal allocation for the senior target-rate classes will be allocated among the individual senior target-rate classes pursuant to "Allocations among the senior classes" below.

(c) for each subordinated class ,

·   the class’s target-rate class percentage of scheduled principal payments on the target-rate strip for that distribution day,

·   plus the class’s proportionate share, based on the principal balances of the subordinated classes, of unscheduled principal payments on the target-rate strip for that distribution day that are not allocated to the senior target-rate classes pursuant to the preceding paragraph (b),

·   plus or minus any amounts that are reallocated to or from the class pursuant to "- Maintenance of subordination" below.

14.3   Unscheduled principal

For each distribution day, the following percentage of unscheduled principal payments on the target-rate strip received during the preceding month will be allocated to the senior target-rate classes:

·   100% if the target-rate class percentage for all the senior target-rate classes on the distribution day exceeds the initial target

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rate class percentage for all the senior target-rate classes.

·   otherwise, and subject to the following proviso, the sum of (1) the target-rate class percentage for the senior target-rate classes, plus (2) the following percentage of the target-rate class percentage for the subordinated classes:

provided , that

·   if the distribution day is one on which the percentage shown in the preceding table is to be reduced - that is, the 61st, 73rd, 85th 97th or 109th distribution day - and either the cumulative loss test or the delinquency test described below are not satisfied, then the percentage will not be reduced on that distribution day or on any subsequent distribution day until both the cumulative loss and delinquency tests are passed, and

·   if the cumulative loss test is not satisfied for a distribution day, the percentage of unscheduled principal payments allocated to the senior target-rate classes will be the greater of the percentage of unscheduled principal payments allocated to the senior target-rate classes for that distribution day calculated in accordance with the preceding rules of this section, or the percentage of unscheduled principal payments allocated to the senior target-rate classes for the preceding distribution day.

The cumulative loss test is satisfied for a distribution day if cumulative realized losses through that distribution day do not exceed the following percentages of the initial principal balance of the subordinated classes:

The delinquency test is satisfied for a distribution day if CitiMortgage certifies to the Trustee that the average of the aggregate scheduled principal balance of mortgage loans delinquent 60 days or more (including, for this purpose, mortgage loans in foreclosure and real estate owned by the Trust as a result of mortgagor default) for that distribution day and the preceding five distribution days is either (1) less than 50% of the average of the principal balance of the subordinated classes for those distribution days, or (2) less than 2% of the average scheduled principal balance of all of the mortgage loans for those distribution days.

If there are composite and component subordinated classes, only the composite subordinated classes are considered in the cumulative loss and delinquency tests.

14.4   Maintenance of subordination

The subordination level for a class (other than a ratio-stripped IO class) is the sum of the class percentages of all classes that are subordinate to that class. If a class’s subordination level on the day before a distribution day is less than the class’s initial subordination level, then the class will have an impaired subordination level on that distribution day.

If a subordinated class has an impaired subordination level on a distribution day, then all principal originally allocated to the subordinated classes will be allocated to the most senior of the subordinated classes with

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an impaired subordination level and to those subordinated classes that are senior to the impaired class, in proportion to their principal balances, up to those classes’ principal balances, and any remainder will be allocated to the remaining subordinated classes, in order of seniority, up to those classes’ principal balances.

Example: Suppose that on a distribution day, (a) each of classes B-1 through B-6 had a principal balance on the preceding day of $1,000, (b) the aggregate principal allocation to the subordinated classes is $3,120, and (c) class B-2 has an impaired subordination level. Then on that distribution day

(1) the entire amount allocated to the subordinated classes will be allocated to classes B-1 and B-2, in proportion to their principal balances, up to their principal balances, and

(2) $1,000 of the remaining $1,120 will be allocated to class B-3, reducing its principal balance to zero, and

(3) the remaining $120 will be allocated to class B-4.

15.1   Order of allocation among senior target-rate classes

On each distribution day before the subordination depletion date, the aggregate scheduled and unscheduled principal allocated to the senior target-rate classes of a group will be allocated to the individual senior target-rate classes of that group as follows:

Group I : Principal allocated to the group I senior target-rate classes from the pool I target-rate strip will be allocated concurrently as follows:

·   9.9510115620% concurrently to classes IA-1 and IA-2, in proportion to their principal balances, until their principal balances are reduced to zero.

·   61.7952874376% concurrently as follows:

b.   80% sequentially in the following order:

·   12.0903823248% sequentially in the following order:

i.   to classes IA-14 and IA-15, the amounts determined under ‘‘NAS classes’’ below;

ii.   to class IA-9, $1,000, until its principal balance is reduced to zero;

iii.   to class IA-7, $382,000, until its principal balance is reduced to zero;

iv.   to class IA-9 until its principal balance is reduced to zero;

v.   to class IA-7 until its principal balance is reduced to zero; and

vi.   concurrently to classes IA-14 and IA-15, in proportion to their principal balances, with out regard to the amounts determined under "nas

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classes" below, until their principal balances are reduced to zero.

·   16.1633186756% sequentially in the following order:

i.   to class IA-16, the amounts determined under ‘‘NAS classes’’ below;

ii.   to class IA-12 until its principal balance is reduced to zero;

iii.   to class IA-16, with out regard to the amounts determined under "NAS classes" below, until its principal balance is reduced to zero.

Group II : Principal allocated to the group II senior target-rate classes from the pool II target-rate strip will be allocated to class IIA-1 until its principal balance is reduced to zero.

Beginning on the subordination depletion date, the priorities stated above will cease to be in effect, and, except as may otherwise be provided in "Super senior and super senior support classes" below, the principal allocation for the senior target-rate classes of each group will be allocated to the senior target-rate classes of the group in proportion to their principal balances on the preceding day.

15.2   NAS classes

Classes IA-13 through IA-16 are non-accelerated senior , or NAS, classes.

For the first 60 distribution days, the principal allocation for a NAS class will be zero.

For distribution day 61 and after, the principal allocation for each NAS class will equal

·   its proportionate share, based on the principal balances of the group’s senior target-rate classes, of scheduled principal payments on the related pool’s target-rate strip allocated to the group’s senior target-rate classes for that distribution day, plus

·   the following percentage of its proportionate share, based on principal balances of the group‘s senior target-rate classes, of unscheduled principal payments on the related pool’s target-rate strip allocated to the group’s senior target-rate classes for that distribution day:

15.3   PAC and TAC classes

There are no planned amortization (or PAC )  classes .

There are no targeted amortization (or TAC )  classes .

16.1   Types of distributions

Each distribution will be either an interest distribution , a principal distribution , a reimbursement , or a residual distribution , as described in "- Distribution priorities" below.

16.2   Accrual and accrual directed classes

There are no accrual or accrual directed classes .

16.3   Distribution priorities

Subject to section 18, "loss recoveries," on each distribution day, the pool distribution amount will be first distributed to any Insurer to pay any insurance premium, and then to the outstanding classes in the following priority (and, if there are any insured classes, the insured payment and amounts withdrawn from the reserve fund will be applied to make payments to the

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insured class certificates as provided in "Insured classes" below):

(1) To each senior class, first , its current interest allocation for that distribution day, and second its interest allocation carryforward from the preceding distribution day, except that an accrual class’s interest distributions may be redirected as described in "- Accrual and accrual directed classes" above. Distributions of current allocations among the senior classes will be in proportion to current interest allocations for, and distributions of interest allocation carryforwards will be in proportion to interest allocation carryforwards to, that distribution day.

(2) (a) To any ratio-stripped PO class, principal up to its principal allocation for that distribution day, and (b) to the senior target-rate classes, principal up to their aggregate principal allocation for that distribution day, to be distributed to the senior target-rate classes in the priorities described in "Allocations among the senior classes - Order of allocation among senior target-rate classes" above.

(3) To each subordinated class, in order of seniority, first , interest up to its interest allocation for that distribution day, and second , principal up to its principal allocation for that distribution day, except that a subordinated class’s principal distribution may be used to reimburse a ratio-stripped PO class, as described in the following paragraph.

(4) Principal distributed to the subordinated classes under the preceding paragraph will be used to reimburse a ratio-stripped PO class up to the amount of (a) any realized subordinated losses previously allocated to the ratio-stripped PO class, and (b) any reduction to the ratio-stripped PO class’s principal balance to reflect the excess of (i) the aggregate principal allocations to the ratio-stripped PO class over (ii) the aggregate principal distributions to the ratio-stripped classes, as described in "Adjustments to class balances" below, to the extent that such losses and reductions were not previously reimbursed under this paragraph (4) or "Loss recoveries" below. Such reimbursements will be taken from distributions to the subordinated classes in order of subordination.

(5) To each class, in order of seniority, a reimbursement of any reduction to the classes’ principal balances to reflect the excess of (a) the aggregate principal allocations to the classes over (b) the aggregate principal distributions to the classes, as described in "Adjustments to class balances" below, to the extent such reductions were not previously reimbursed. Classes with equal seniority will share in the reimbursement in proportion to such unreimbursed reductions.

(6) To the residual certificates, a residual distribution of the remaining pool distribution amount.

A class that is no longer outstanding cannot receive a distribution.

Notwithstanding anything to the contrary in this agreement, no distribution will be made to a subordinated class on a distribution day if on that distribution day the principal balance of a more senior class would be reduced by any part of the principal portion of a realized subordinated loss.

16.4   Distributions to certificate holders

On each distribution day, distributions to a class will be distributed to the holders of the certificates of the class in proportion to the principal or notional balances of their certificates.

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16.5   Final distribution on the residual certificates 

Upon termination of the Trust in accordance with section 9.1, "Termination upon repurchase by CMSI or liquidation of all mortgage loans," any class PR certificates, and if there are no class PR certificates, the LR certificates will receive all amounts remaining in the certificate account and in any retail reserve fund after all required distributions on the certificates, and any required distributions to any Insurer, have been made.

16.6   Wire transfer eligibility

The minimum number of single certificates eligible for wire transfer on each distribution day, for the certificates, is 1,000 (representing a $1,000,000 initial principal balance or initial notional balance) and, for the residual certificates, a 100% percentage interest.

On each distribution day, the principal balance of each class that is not an IO class will be adjusted, in the following order, as follows:

(1) The principal balance of any ratio-stripped PO class will be reduced by realized losses on its PO strip for the preceding month.

(2) The aggregate principal balance of the target-rate classes will be reduced by the principal portion of realized non-subordinated losses on the target-rate strip for the preceding month. The reduction will first be allocated between the subordinated classes, collectively, and the senior target-rate classes, collectively, in proportion to aggregate principal balances. The reduction for the subordinated classes will be allocated to the individual subordinated classes in proportion to their principal balances. The reduction for the senior target-rate classes will be allocated to the individual senior target-rate classes in proportion to their principal balances, except that the principal balance of an accrual class will be deemed to be the lesser of its principal balance or its initial principal balance.

(3) To the extent that on the distribution day an interest distribution to an accrual class is redirected to an accrual directed class, the principal balance of the accrual class will be increased.

(4) The principal balance of each class will be reduced by its principal distributions for that distribution day, including

(a) principal distributions to an accrual directed class that are redirected from interest distributions to an accrual class, and

(b) principal distributions to a subordinated class, even if part or all of those principal distributions are, pursuant to section 16.3(4), used to reimburse a ratio-stripped PO class.

However, any portion of an accrual class’s interest distribution that, on the distribution day before the class’s accrual termination day, is distributed as principal to the accrual class itself, will neither increase nor decrease the class’s principal balance.

(5) The aggregate principal balance of the target-rate classes will be reduced by the principal portion of realized subordinated losses on the target-rate strip for the preceding month. The reductions will be applied first to the subordinated classes in order of subordination, in each case until the principal balance of the class is reduced to zero. If the realized subordinated losses exceed the principal balance of the subordinated classes, the principal balance of the senior target-rate classes will be reduced by the amount of the excess. The

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excess will be allocated among the senior target-rate classes in proportion to their principal balances, except that for this allocation, the principal balance of an accrual class will be deemed to be the lesser of its principal balance or its initial principal balance.

(6) The principal balance of any ratio-stripped PO class will be reduced by the excess of (a) the class’s principal allocation over (b) the class’s principal distribution for that distribution day.

(7) The principal balance of each target-rate class will be reduced, in order of subordination, in an aggregate amount equal to the excess of (a) the aggregate principal allocations to the target-rate classes over (b) the aggregate principal distributions to the target-rate classes. Classes of equal seniority will share in such reduction in proportion to the amounts by which the principal allocation to each such class exceeded its principal distribution.

For purposes of the preceding paragraphs (1) through (7),

·   the principal portion of a debt service reduction will not be considered a realized loss, and

·   references to the class principal balances in any paragraph mean the principal balances after the adjustments required by the preceding numbered paragraphs.

Where the principal balance of a class is reduced due to a realized loss under the preceding paragraphs (1), (2) or (5), the loss will be said to be allocated to the class (an allocated loss ) to the extent of the reduction.

The following rules for loss recoveries supersede any conflicting rules in "Distributions" or "Adjustments to class balances" above.

On each distribution day, the amount of any loss recovery for the preceding month will be distributed as follows:

First , to each senior class to the extent of and in proportion to its aggregate realized losses for that and all preceding months that were not previously reimbursed under this paragraph or, for a ratio-stripped PO class, paragraph 4 of "Distributions — Distribution priorities" above.

Second , to the target-rate classes in the same manner as a distribution of unscheduled principal.

Distributions made pursuant to paragraph First above will not result in any adjustments to class balances, but distributions made pursuant to paragraph Second above will result in the normal adjustments to the class balances described in paragraph 4 of "Adjustments to class balances" above.

The principal balances of the subordinated classes will be increased in order of seniority to the extent of their aggregate realized losses for that and all preceding months that were not previously reimbursed under this paragraph, up to an aggregate amount for all subordinated classes equal to the loss recovery less the amounts distributed to the senior classes under paragraph First above.

Example: In May, there is a $1,000 loss recovery. On the June distribution day, prior to any distributions or adjustments, the senior classes have aggregate unreimbursed losses of $100 of losses that were not subject to subordination and the subordinated classes have aggregate unreimbursed losses of $700. (Unreimbursed losses can be less than the recovery if some classes that previously absorbed losses are no longer outstanding.) Then on the June distribution day,

1   $100 of the loss recovery will be distributed to the senior classes to reimburse

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them for previously allocated losses, but the distribution will not reduce the principal balances of the senior classes.

2   The remaining $900 of the loss recovery will be distributed to the target-rate classes in the same manner as unscheduled principal, and class balances will be reduced by the amount of the distributions.

3   The principal balances of the subordinated classes will be increased by $700, in order of seniority up to the amount of unreimbursed losses.

If expenses on the liquidated loans for any month exceed the amounts recovered on the liquidated loans for the month, the excess will be treated as a realized loss on the mortgage loans.

The preceding provisions for allocations and distributions, and for adjustments to class balances, are subject to the following sections on LIBOR classes, composite and component classes, multiple-pool series, retail classes, and insured classes.

Classes IA-3, IA-4, IA-9 and IA-10 are LIBOR classes .

Each LIBOR class will have a monthly LIBOR accrual period from the day of the month indicated in the footnotes to the table in "The Series - General terms for classes" above through the day preceding the first day of the next LIBOR accrual period. The first LIBOR accrual period for a class will be the latest possible LIBOR accrual period that ends before the first distribution day.

Example: The LIBOR accrual period for a LIBOR class begins on the 25th day of the month, and the first distribution day is February 25, 200x. Then the first LIBOR accrual period for the class begins on January 25, 200x and runs through February 24, 200x, the second LIBOR accrual period begins on February 25, 200x and runs through March 24, 200x, and so forth.

A LIBOR class will not accrue interest for any period before its first LIBOR accrual period. The interest rate for each LIBOR class is stated in "The series - General terms for classes" above.

CitiMortgage will determine LIBOR for each LIBOR accrual period (after the first LIBOR accrual period) on the second business day before the beginning of each LIBOR accrual period as follows:

·   LIBOR for any determination day will be the British Bankers Association LIBOR rate for US dollar deposits with a one-month maturity at 11AM, London time on that day, as such rate appears on Telerate Page 3750, Bloomberg Page BBAM, or another page of these or any other financial reporting service in general use in the financial services industry, rounded upward, if necessary, to the nearest multiple of 1/16 of 1%.

·   If no rate is so reported on that day, CitiMortgage will determine LIBOR on the basis of the rates on that day at approximately 11AM, London time, at which deposits in U.S. Dollars with a maturity of one month in a principal amount of not less than U.S. $1 million and representative for a single transaction in that market at that time, are offered to prime banks in the London interbank market for at least four major banks in the London interbank market selected by CitiMortgage. CitiMortgage will request the principal London office of each such bank to provide a quotation of its rate. If at least two such quotations are provided, LIBOR will be the arithmetic mean of those quotations.

·   If fewer than two quotations are provided, LIBOR will be the arithmetic mean of the rates quoted at approximately

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11AM, New York time, on that day by three major banks in New York City selected by CitiMortgage for loans in U.S. Dollars to leading European banks having a maturity of one month in a principal amount of not less than U.S. $1 million that is representative for a single transaction in such market at such time. If the banks selected by CitiMortgage are not quoting such rates, LIBOR will be LIBOR for the preceding LIBOR accrual period.

CitiMortgage may designate an affiliate or a third party to determine LIBOR.

The composite classes of the series, and each composite class’s component classes are shown in the table in "The series - General terms for classes" above.

Each composite class is comprised of two or more component classes. Certificates are only issued for composite classes. Component classes cannot be severed from their composite classes, and cannot be separately transferred. Component classes are, however, considered classes for all purposes of the preceding sections on allocations and distributions except that all distributions to the component classes of a composite class will become distributions to the composite class. A composite class is not considered a class for purposes of allocations and distributions, but instead receives all the distributions made to any of its component classes. Voting is by composite, not component, classes.

In a multiple-pool series, each subordinated class is a composite class formed of two or more component classes. Unless otherwise specified, references to a "subordinated class" mean the composite class.

This is a multiple-pool series. The mortgage loans of this series are divided into two pools. Pool I consists of the mortgage loans described in exhibit B-1, and Pool II consists of the mortgage loans described in exhibit B-2.

Each class of this series (other than certain composite classes) belongs to a group of classes related to a specific pool. The designation of each class in a group bears the roman numeral prefix of its related pool, and the group is referred to by that prefix.

Example: Classes related to pool I bear the prefix "I," as IA-1, IB-1, etc., and are referred to collectively as "group I."

With exceptions described below, the classes of each group are treated like a separate series, with allocations to the classes of the group being based solely on payments on the related pool. Any ratio-stripping will be done on a pool basis, so that there will be separate PO, IO and target-rate strips for each pool, with the related group having its own target-rate, and ratio-stripped IO and PO, classes.

The subordinated classes of each group will be component classes. A ratio-stripped IO or PO class of a group will only be a component class if so designated in "The series - General terms for classes" above.

22.1   Adjustment of subordinated component class principal balances

On each distribution day, the aggregate amount of any

·   realized subordinated losses on the mortgage loans in a pool, or

·   excess of the aggregate principal allocations to the related group’s target-rate classes over the aggregate principal distributions to those classes,

that, in accordance with "Adjustments to class balances" above, would reduce the principal balances of the group’s

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subordinated component classes in order of subordination if the pool and the related groups were considered a separate series, will instead reduce

·   the principal balances of the subordinated composite classes in order of subordination, and

·   the aggregate principal balance of the group’s subordinated component classes,

by that amount.

Such reduction in the aggregate principal balance of a group’s subordinated component classes will result in adjustments to the principal balance of the subordinated component classes of each group so the ratio of the principal balances of the component classes from each group will be the same for each subordinated composite class.

Example: Assume subordinated composite classes B-1 through B-6, each with a principal balance of $1,000. There are two groups, I and II, and the aggregate principal balance of each group’s subordinated component classes is $3,000. Then for each subordinated composite class, the ratio of the principal balance of its group I component class to the principal balance of its group II component class must be 1 to 1. Consequently, both the group I and the group II component class of each subordinated composite class will have a principal balance of $500.

Now assume a $750 subordinated loss in pool I. Then

·   the principal balance of class B-6 will be reduced by $750, to $250, which will reduce the aggregate principal balance of the subordinated composite classes to $5,250,

·   the aggregate principal balance of the group I subordinated component classes will be reduced by $750, to $2,250, while the aggregate principal balance of the group II subordinated component classes will remain at $3,000;

·   the ratio of the aggregate principal balance of the group I subordinated component classes to the aggregate principal balance of the group II subordinated component classes will be $2,250 to $3,000, or 3 to 4;

·   for classes B-1 through B-5, the principal balance of the composite class will remain at $1,000, but the principal balance of its group I component class will be approximately $428.57, and the principal balance of its group II component class will be approximately $571.43 (a ratio of 3 to 4); and

·   class B-6’s principal balance of $250 will be comprised of a group I component class with a principal balance of approximately $107.14, and a group II component class with a principal balance of approximately $142.86 (a ratio of 3 to 4).

If subordinated losses on a mortgage pool for a distribution day exceed the aggregate principal balance of the subordinated component classes of the related group, the aggregate principal balance of such component classes will be reduced to zero, and the aggregate principal balance of the subordinated component classes of the other groups will be reduced by the excess.

Example: Suppose that in the series in the preceding example, the group I subordinated component classes and the group II subordinated component classes each have an aggregate initial principal balance of $3,000, and that each subordinated composite class, B-1 through B-6 has a principal balance of $1,000. Now suppose that there are $4,000 of subordinated losses on the mortgage loans in pool II’s target-rate strip, but no losses on the mortgage loans in pool I’s target-rate strip. Then the entire $4,000 of losses will be allocated to the subordinated classes, reducing the principal balance of classes B-3 through B-6 to zero. Classes B-1 and B-2 will each retain a principal balance of $1,000, comprised of a group I component class with a principal balance of $1,000 and a group II component class with a principal balance of $0. The principal balance of the subordinated group

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I component classes will thus be reduced by $1,000 even though there are no losses on the pool I target-rate strip.

Subject to "- Undercollateralization" below, if realized subordinated losses on a distribution day exceed the aggregate principal balance of the subordinated classes, the aggregate principal balance of the senior classes in each group will be reduced by the group’s proportionate share of the excess losses, based on the proportions of all the losses for that distribution day in the mortgage loan pools.

Example: Assume that for a distribution day, there are $2,250 of realized subordinated losses in pool I and $4,500 of realized subordinated losses in pool II. The aggregate principal balance of the subordinated classes is only $6,000. Then the principal balance of the subordinated classes will be reduced to $0, and the remaining $750 of losses will reduce the aggregate principal balance of the senior classes of group I by $250 (or 1/3 of $750), and will reduce the aggregate principal balance of the senior classes of group II by $500 (or 2/3 of $750). The principal balances of the component classes of the subordinated classes are irrelevant for these purposes.

22.2   Maintenance of subordination

Impairment of subordination for subordinated classes of a multiple-pool series will be determined based on composite, not component, classes. In determining whether a composite class has an impaired subordination level, the principal balance of the composite class will equal the sum of the principal balances of its component classes. If a subordinated composite class has an impaired subordination level, then principal will be allocated among the subordinated composite classes pursuant to "Allocations - Maintenance of subordination" above, and, for purposes of adjusting principal balances, will be further allocated to the component classes in proportion to their principal balances.

22.3   Distribution shortfalls

If on a distribution day, payments on the mortgage loans in the target-rate strip for a pool are not sufficient to permit payments of any insurance premium due to an Insurer, and all interest and principal allocated to the senior target-rate classes of the related group, then the pool may receive insurance premium, interest and principal distributions from payments on the mortgage loans in another pool once any insurance premium due is paid to the Insurer, and full interest and principal distributions are made to the senior target-rate classes of the group related to the other pool.

Example: Suppose that there are two groups of classes and that on a distribution day, cash available for distribution to the group I senior-target rate classes from payments on the pool I mortgage loans is $1,000 less than the aggregate interest and principal allocations to group I’s senior target-rate classes, while cash available for distribution to the group II senior-target rate classes from payments on the pool II mortgage loans exceeds the aggregate interest and principal allocations to group II’s senior target-rate classes by $1,500. Then $1,000 of the extra $1,500 available to group II will be used to make full interest and principal distributions to the group I senior target-rate classes, and only the remaining $500 will be distributed to the group II subordinated component classes.

If there are several pools for which mortgage loan payments do not provide enough cash for full distributions to the senior target-rate classes and any Insurer, the related groups will receive cash from other pools in proportion to the aggregate amount by which any insurance premium due to an Insurer, and interest and principal distributions would otherwise fall short of

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interest and principal allocations. If there are several pools where mortgage loan payments provide cash in excess of the amount required for full distributions, they will provide cash to the senior target-rate classes, and any Insurer, of those groups related to the other pools in proportion to the amounts of the excess.

22.4   Undersubordination

If on a distribution day before the subordination depletion date, the principal balances of all the senior target-rate classes of any group (but not the principal balances of all the group’s subordinated component classes) have been reduced to zero, and there is undersubordination (as defined below), then on that distribution day, before any distributions are made,

·   the pool distribution amount of the group will be reduced by an amount (the reduction amount ) equal to the lesser of (1) unscheduled principal payments on the related pool’s target-rate strip received by the Trust during the preceding month and (2) the excess, determined without regard to this section "- Undersubordination," of the pool distribution amount over the amount required to be used to reimburse any ratio-stripped PO classes,

·   the principal allocation to each class in the group will be reduced by the class’s proportionate share, based on principal balances, of the reduction amount,

·   the pool distribution amount of each group whose senior target-rate classes have not been reduced to zero will be increased by a proportionate share of the reduction amount based on the aggregate principal balance of the senior target-rate classes of each such group, and

·   the aggregate principal allocation for the senior target-rate classes of each group whose senior target-rate classes have not been reduced to zero will be increased by the portion of the reduction amount added to its pool distribution amount, which increased aggregate allocation will be further allocated among the senior target-rate classes in accordance with the rules in "Allocations among the senior target-rate classes" above.

There is undersubordination on a distribution day if either

·   the subordination level of the senior classes (without regard to group) on that distribution day is less than 200% of the initial subordination level of the senior classes, or

·   the aggregate scheduled principal balance of the mortgage loans in any pool that are delinquent 60 days or more (including for this purpose mortgage loans in foreclosure and real estate owned by the Trust as a result of Mortgagor default), averaged over the last six months, is 50% or more of the principal balance of the related group’s subordinated component classes.

22.5   Undercollateralization

Because losses on a mortgage loan may be allocated in part to the subordinated component classes of a different group, the scheduled principal balance of a pool’s target-rate strip could differ from the aggregate principal balance of the related group’s target-rate classes. If the scheduled principal balance of a pool’s target-rate strip is less than the aggregate principal balance of the related group’s target-rate classes, the group will be undercollateralized by the amount of the difference; conversely, if the scheduled principal balance of a pool’s target-rate strip is more than the aggregate principal balance of the related group’s target-rate classes, the group will be overcollateralized by the amount of the difference.

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If a group is undercollateralized, the normal distribution rules will be adjusted as follows:

(1) To the extent that scheduled interest payments on the target-rate strip of a pool related to an overcollateralized group exceed the aggregate interest allocations to that groups’ target-rate classes, plus any insurance premium due to an Insurer, that excess, up to the amount of any interest allocation carryforwards that the undercollateralized group would otherwise experience on that distribution day and the insurance premium, will be deducted from the pool distribution amount for the overcollateralized group and added to the pool distribution amounts for the undercollateralized group. If there is more than one such undercollateralized group, or more than one overcollateralized group, then (a) amounts will be deducted from the pool distribution amounts for the groups that are overcollateralized in proportion to such excess interest payments, up to the aggregate amount of such interest allocation carryforwards and the insurance premium for the undercollateralized groups, and (b) amounts will be added to the pool distribution amounts of the undercollateralized groups in proportion to the amount of such interest allocation carryforwards and insurance premium.

(2) Before the subordination depletion date, if one or more groups is undercollateralized and the principal balance of each of the groups’ subordinated component classes has been reduced to zero, then (a) all amounts that (after required reimbursements to any ratio-stripped PO classes) would otherwise be distributed as principal to the subordinated component classes of the other groups, up to the aggregate amount by which such undercollateralized groups are undercollateralized, will, in proportion to the aggregate principal balance of the subordinated component classes of such other groups, be deducted from the pool distribution amount and the principal allocations to the subordinated component classes of such other groups, and (b) such amount will be added to the pool distribution amounts and the principal allocations of the target-rate classes of such undercollateralized groups, in proportion to the amount by which such groups are undercollateralized.

(3) After the subordination depletion date, if a group is undercollateralized, then

·   once a group’s target-rate classes are all reduced to zero, principal payments on the related pool’s target-rate strip will be added to the pool distribution amount and to the principal allocations of the target-rate classes of the undercollateralized groups, in proportion to the amount by which they are undercollateralized, and

·   realized losses on the target-rate strips of the pools related to the overcollateralized groups will, up to the amount by which the group is overcollateralized, not reduce the principal balances of the target-rate classes of those groups, but will instead reduce the principal balances of the target-rate classes of the undercollateralized groups, in proportion to the amount by which they are undercollateralized, and in accordance with "Adjustments to class balances" above. If there is more than one overcollateralized group, the losses that will not reduce principal balance will be in proportion to the amount by which each group is overcollateralized. If there is more than one undercollateralized group, the aggregate reductions in principal balances for each group will be in proportion to the amounts by which such groups are undercollateralized.

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22.6   Non-subordinated interest shortfalls

Prior to the subordination depletion date, reductions to interest allocations due to (a) interest shortfalls due to the federal Servicemembers Civil Relief Act or any comparable state laws and (b) non-supported prepayment interest shortfalls will be allocated pro-rata to all the classes of all the groups, regardless of the pools in which the shortfalls originate.

From and after the subordination depletion date,

·   interest shortfalls due to the federal Servicemembers Civil Relief Act or any comparable state laws will be separately calculated for each pool, and will be allocated solely to the classes of the related group, and

·   the compensating cap and non-supported prepayment interest shortfalls will be separately calculated for each pool, and non-supported prepayment interest shortfalls for a pool will be allocated solely to the classes of the related group.

The following table lists the super senior classes, and their respective super senior support classes .

After the subordination depletion date, losses (other than non-subordinated losses) on a target-rate strip that would otherwise reduce the principal balance of the super senior classes will instead reduce the principal balance of the super senior support class up to any support amount shown above for such class.

For these purposes, the principal balance of a super senior support class on a distribution day will be determined after giving effect to the adjustments described in paragraphs (2) through (5) of section 17, "Adjustments to class balances," for that distribution day (which include the reductions for non-subordinated losses, principal distributions and realized subordinated losses), but before the adjustments required by this section 23.

There are no retail classes . There is no retail reserve fund .

There are no insured classes . There is no Insurer , certificate insurance policy , insurance premium , or reserve fund .

There is/are no advance account , advance account advances , advance account available advance amount , advance account depository , advance account depository agreement , advance account funding date , or advance account trigger date , Paying Agent failure , or Paying Agent failure advance .

27.1   Constituent REMICs

(a) CMSI and the Trustee will make the appropriate elections to treat the Trust Fund, and the affairs of the Trust Fund will be conducted so as to qualify the Trust Fund, for federal income tax purposes as three separate constituent REMICs - the pooling REMIC , the lower-tier REMIC , and

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the  upper-tier REMIC . The pooling REMIC will be the applicable constituent REMIC for purposes of section 3.21.

The assets of the pooling REMIC will consist of the mortgage loans, such amounts as may from time to time be held in the certificate account, any insurance policies relating to a mortgage loan, and property that secured a mortgage loan and that has been acquired by foreclosure or deed in lieu of foreclosure and all proceeds thereof. Classes IA-IO, IIA-IO, A-PO and the class P regular interests described below, are designated as the regular interests in the pooling REMIC within the meaning of Internal Revenue Code Section 860G(a)(1). Class PR is designated as the residual interest in the pooling REMIC within the meaning of Internal Revenue Code Section 860G(a)(2).

The assets of the lower-tier REMIC will consist of the class P regular interests described below, the Trustee’s rights under any certificate insurance policy and reserve fund, any retail reserve fund, and any assets in the lower-tier REMIC account described below. Classes IA-1, IA-2. IA-5, IA-6, IA-11 through IA-16, IIA-1, and B-1 through B-6, and any class L regular interests described below, are designated as the regular interests in the lower-tier REMIC. Class LR is designated as the residual interest in the lower-tier REMIC.

The assets of the upper-tier REMIC will consist of any class L regular interests described below, and any assets in the upper-tier REMIC account described below. Classes IA-3, IA-4, and IA-7 through IA-10 are designated as the regular interests in the upper-tier REMIC. Class R is designated as the residual interest in the upper-tier REMIC.

27.2   The class P and class L regular interests

There are four uncertificated class P regular interests , each designated as "CMALT (CitiMortgage Alternative Loan Trust), Series 2007-A4 REMIC Pass-Through Certificates," and further individually designated as a

·   "PI-M regular interest,"

·   "PI-Q regular interest,"

·   "PII-M regular interest," and

·   "PII-Q regular interest."

There are three uncertificated class L regular interests , designated as "CMALT (CitiMortgage Alternative Loan Trust), Series 2007-A4 REMIC Pass-Through Certificates," and further designated as the "LI-3 regular interest," the "LI-7 regular interest," and the "LI-9 regular interest."

The initial principal or notional balances and certificate rates of the class P and any class L regular interests are:

The Trustee acknowledges that it is holding the class P regular interests as assets of the lower-tier REMIC and any class L regular interests as assets of the upper-tier REMIC.

27.3   Principal distributions and loss allocations to class L and class P regular interests

On each distribution day,

·   the class LI-3 regular interest will receive a principal distribution, or allocation of the principal portion of realized losses,

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equal in the aggregate to the principal distribution, or allocation of the principal portion of realized losses, for that day, on class IA-3,

·   the class LI-7 regular interest will receive a principal distribution, or allocation of the principal portion of realized losses, equal in the aggregate to the principal distribution, or allocation of the principal portion of realized losses, for that day, on class IA-7, and

·   the class LI-9 regular interest will receive a principal distribution, or allocation of the principal portion of realized losses, equal in the aggregate to the principal distribution, or allocation of the principal portion of realized losses, for that day, on class IA-9.

For each distribution day, and for each pool x and y , a P x -M regular interest will receive distributions of principal, or allocation of the principal portion of realized losses on the related target-rate strip, so as to keep its principal balance (computed to $.000001) equal to 0.01% of the aggregate principal balance of the subordinated component classes of the related group. However, if the ratio of the principal balance of a P x -M regular interest to the principal balance of a P y -M regular interest is not the same as the ratio of the aggregate principal balance of the component classes x B-1 through x B-6 to the aggregate principal balance of the component classes y B-1 through y B-6, then the least amount of principal will be distributed to the P x -M or P y -M regular interest, as applicable, so that the ratio of the principal balance of the P x -M regular interest to the principal balance of the P y -M regular interest will be the same as the ratio of the aggregate principal balance of the component classes x B-1 through x B-6 to the aggregate principal balance of the component classes y B-1 through y B-6. Also, for such distribution day, the Px-Q regular interest will receive the balance of the principal distribution, and allocation of the principal portion of realized losses on its related target-rate strip.

Recoveries of previously allocated realized losses of principal will be allocated to any class P and class L regular interests in the same manner as realized losses were allocated to them.

27.4   Interest distributions to class L and class P regular interests

On each distribution day, each class P or class L regular interest will receive an interest distribution at its certificate rate, and interest shortfalls and the interest portion of realized losses for the related target-rate strip will be allocated to such regular interest in the same proportion as interest is allocated to them, provided that

·   (a) prior to the subordination depletion date, non-supported prepayment interest shortfalls will be allocated pro-rata to all the class P regular interests, regardless of the pool in which the shortfalls originate, and (b) from and after the subordination depletion date, non-supported prepayment interest shortfalls for any pool x (where x is a variable for pool designations I, II, etc .) will be allocated solely to the P x -M and P x -Q regular interests, and

·   (a) prior to the subordination depletion date, any class L regular interest will be allocated its proportional share, based on accrued interest of any lower-tier REMIC regular interests, of non-supported prepayment interest shortfalls, regardless of the pool in which the shortfalls originate, and (b) from and after the subordination depletion date, any class L regular interest will be allocated its proportional share, based on accrued interest of any class L regular interests and the other lower-tier

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REMIC regular interests designated class x A, of non-supported prepayment interest shortfalls for pool x .

No interest shortfall amount or unpaid interest shortfall on any class P or class L regular interest will bear interest.

27.5   REMIC accounts and distributions

(a) CitiMortgage, the Trustee and the Paying Agent will

·   perform their duties in a manner consistent with the REMIC provisions of the Internal Revenue Code, and will not knowingly take or fail to take any action that would adversely affect the continuing treatment of the Trust Fund as segregated asset pools and the treatment of each such segregated asset pool as a REMIC or would result in the imposition of a tax on the Trust Fund, or any constituent REMIC, and

·   carry out their covenants in this agreement and the elections and reporting required in section 3.15 on behalf of each constituent REMIC, including maintaining the following segregated accounts:

·   the certificate account,

·   if there is a pooling REMIC, a pooling REMIC account,

·   a lower-tier REMIC account , and

·   if there is an upper-tier REMIC, an upper-tier REMIC account .

Any pooling REMIC account, the lower-tier REMIC account, and any upper-tier REMIC account will be established in the same manner as the certificate account.

CitiMortgage, on behalf of the Trustee, will deposit daily in the certificate account in accordance with section 3.3 all remittances received by it, any amounts required to be deposited in the certificate account pursuant to section 3.2, all other deposits required to be made to the certificate account other than those amounts specifically designated to be deposited in any pooling REMIC account, the lower-tier REMIC account, or any upper-tier REMIC account in this section, "REMIC accounts and distributions," and all investments made with moneys on deposit in the certificate account, including all income or gain from such investments, if any. Funds on deposit in the certificate account will be held and invested in accordance with the applicable provisions of section 3.2 and 3.20. Distributions from the certificate account will be made in accordance with sections 3.6, 3.8 and these Series Terms to make payments in respect of the regular and residual interests in any pooling REMIC, the lower-tier REMIC, and any upper-tier REMIC and to pay servicing fees in accordance with section 3.6(h) and any insurance premium.

Notwithstanding anything herein to the contrary, regular and residual interests in any pooling REMIC, the lower-tier REMIC, and any upper-tier REMIC will not receive distributions directly from the certificate account. On each distribution day,

·   if there is a pooling REMIC, CitiMortgage, on behalf of the Trustee, will withdraw from the certificate account and deposit by 12 noon in the pooling REMIC account all distributions to be made on such distribution day in respect of interest on or in reduction of the principal balance of any class P regular interests, and

·   if there is no pooling REMIC, CitiMortgage, on behalf of the Trustee, will withdraw from the certificate account and deposit by 12 noon in the lower-tier REMIC account all distributions to be made on such distribution day in respect of interest on or in reduction of the principal balance of the regular interests in the lower-tier REMIC.

If there is an upper-tier REMIC, CitiMortgage, on behalf of the Trustee, will immediately thereafter withdraw from the lower-tier REMIC account and deposit in

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the upper-tier REMIC account all distributions to be made on such distribution day in respect of interest on or in reduction of the principal balance of any class L regular interests.

The Trustee will cause to be distributed from the lower-tier REMIC account and any upper-tier REMIC account, to the extent funds are on deposit therefor, all amounts required to be distributed with respect to the regular and residual interests in the lower-tier REMIC and any upper-tier REMIC as specified in these Series Terms.

To the extent that any part of the lower-tier REMIC account or any upper-tier REMIC account is designated in these Series Terms as an investment account, the provisions in section 3.19 applicable to the investment of funds will apply to such REMIC accounts. In addition, section 3.3(a) regarding commingling will apply to such REMIC accounts.

(b) CitiMortgage will maintain books for constituent REMICs on a calendar year taxable year and on the accrual method of accounting.

(c) The Trustee will not create, or permit the creation of, any "interests" in any constituent REMIC within the meaning of Internal Revenue Code Section 860D(a)(2) other than the interests represented by the certificates or, if there are multiple REMICs, the uncertificated regular interests in any pooling REMIC or (if there is an upper-tier REMIC) the lower-tier REMIC.

(d) Except as otherwise provided in the Internal Revenue Code, CitiMortgage will not grant, and neither CitiMortgage nor the Trustee will accept, property unless (i) substantially all of the property held by each constituent REMIC constitutes either "qualified mortgages" or "permitted investments" as defined in Internal Revenue Code Sections 860G(a)(3) and (5), respectively, and (ii) no property will be granted to a constituent REMIC after the startup day, unless the grant would not subject the constituent REMIC to the 100% tax on contributions to a REMIC after the startup day imposed by Internal Revenue Code Section 860G(d).

(e) The Trustee will not accept on behalf of the Trust Fund or a constituent REMIC any fee or other compensation for services and will not accept on behalf of the Trust Fund any income from assets other than those permitted to be held by a REMIC.

(f) Neither CitiMortgage nor the Trustee will sell or permit the sale of all or any portion of the mortgage loans, or of an Eligible Investment held in the certificate account or in any REMIC account (other than in accordance with sections 2.2, 2.3, 2.4 and 3.19(a)) unless such sale is pursuant to a "qualified liquidation" as defined in Internal Revenue Code Section 860F(a)(4)(A) and is in accordance with section 9.1.

27.6   Tax matters person

If in any taxable year there will be more than one holder of any class of residual certificates, a tax matters person may be designated for the related REMIC, who will have the same duties for the related REMIC as those of a "tax matters partner" under Subchapter C of Chapter 63 of Subtitle F of the Internal Revenue Code, and who will be, in order of priority, (i) CitiMortgage or an affiliate of CitiMortgage, if CitiMortgage or such affiliate is the holder of a residual certificate of the related REMIC at any time during the taxable year or at the time the designation is made, (ii) if CitiMortgage is not a holder of a residual certificate of the related REMIC at the relevant time, CitiMortgage as agent for the holder of the residual certificate of the related REMIC, if the designation is permitted to be made

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under the Internal Revenue Code, or (iii) the holder of a residual certificate of the related REMIC or person who may be designated a tax matters person in the same manner in which a tax matters partner may be designated under applicable Treasury Regulations, including Treas-ury Regulations § 1.860F-4(d) and tem-porary Treasury Regulations § 301.-6231-(a)-(7)-1T.

28.1   Yield maintenance agreement

Class IA-9 is a class of yield protected certificates .

The Trustee is hereby directed to enter into one or more yield maintenance agreements (together, the yield maintenance agreement ) with Morgan Stanley Capital Services Inc., (the yield maintenance provider ) in substantially the form attached as exhibit F. The yield maintenance agreement is an asset of the Trust, but not of any constituent REMIC.

Payments to the yield maintenance provider will be made by Morgan Stanley, and the Trustee will have no responsibility for such payments.

Under the yield maintenance agreement, the yield maintenance provider will make yield maintenance payments for the benefit of the holders of the yield protected certificates.

Each yield maintenance payment for a class of yield protected certificates will be a per annum percentage (the yield   maintenance percentage ) of an assumed principal balance for the class for the relevant distribution day. The yield maintenance percentage will equal the excess of LIBOR for that distribution day over the maximum LIBOR  shown below for the class, up to the maximum protection percentage shown for that class.

Where the annual rate for a class of certificates is specified as LIBOR plus a percentage margin , subject to a maximum rate, the maximum LIBOR will be the excess of the maximum rate over the margin.

Example: Suppose the annual interest rate formula for a class of yield protected certificates is LIBOR + 0.5%, subject to a maximum rate of 6%. Then 0.5% is the margin, and the maximum LIBOR is 5.5% (the 6% maximum rate minus the 0.5% margin). In the absence of a yield maintenance agreement, even if LIBOR is over 5.5% for a distribution day, certificate holders can not receive interest at an annual rate of more than 6%.

Now suppose that for a distribution day, LIBOR is 6.3% and the actual principal balance of the class is $2 million, and that under a yield maintenance agreement for the class, the maximum protection percentage is 3%, and the assumed principal balance for the distribution day is $1.6 million. Accordingly, the class will receive a yield maintenance payment equal to one-twelfth of 0.8% (the excess of 6.3% over the maximum LIBOR of 5.5%) of $1.6 million (the assumed principal balance), or approximately $1,067.

What if LIBOR had been 9% rather than 6.3%? The excess of 9% over 5.5% is 3.5%, which is greater than the maximum protection percentage of 3%. Therefore, the class will receive an additional payment of only one-twelfth of 3% of $1.6 million, or $4,000.

The yield maintenance payments for each class of yield protected certificates will be made to the paying agent, who will pass them through to the holders of the class of certificates in proportion to the principal balances of their certificates, but not more than will be required to pay the certificates

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an amount (the yield maintenance amount ) for that distribution day equal to the yield maintenance percentage of the actual principal balance for the class for that distribution day.

Example: Same as previously, with LIBOR 6.3%, but an assumed principal balance of $3 million, which exceeds the actual principal balance of $2 million. The yield maintenance provider will make a yield maintenance payment to the paying agent of one-twelfth of 0.8% of $3 million (the assumed principal balance), or approximately $2,000, but the class will receive only the yield maintenance amount of one-twelfth of 0.8% of $2 million (the actual principal balance), or approximately $1,333.

If for any distribution day, the yield maintenance payment by the yield maintenance provider to the paying agent for a class of certificates exceeds the yield maintenance amount required to be paid to the holders of that class, the excess will be deposited in a yield maintenance reserve fund for that class maintained in an account at the paying agent.

If for any distribution day, the assumed principal balance is less than the aggregate outstanding principal balance of a class of yield protected certificates, the yield maintenance payment will be less than the yield maintenance amount for the distribution day, and a shortfall will result. Amounts in the yield maintenance reserve fund for the class will be used to cover the shortfall.

Once the principal balance of a class of yield protected certificates has been reduced to zero, or the Trust has been terminated, any funds remaining in the yield maintenance reserve fund will be paid to Morgan Stanley. Thereafter, any payments resulting from the yield maintenance agreement for the class will be paid to Morgan Stanley.

The yield maintenance reserve fund may not be invested.

The yield maintenance reserve fund will be treated as an "outside reserve fund" under the REMIC provisions, beneficially owned by Morgan Stanley, who will be taxable on all such amounts or income thereon, and who will be entitled to any reimbursement from the REMICs with respect thereto.

28.2   Tax treatment

CitiMortgage will treat the portion of the Trust that holds the right of the yield protected certificates to receive payments under the yield maintenance agreement and the yield maintenance reserve fund as a grantor trust for federal income tax purposes. The yield maintenance agreement and the yield maintenance reserve fund are not assets of any REMIC. 

CitiMortgage will treat the holders of the yield protected certificates as the beneficial owners of a notional principal contract representing the right to receive payments under the yield maintenance agreement and Morgan Stanley as the beneficial owner of the yield maintenance reserve fund, including any payments under the yield maintenance agreement that exceed the payments distributable to the holders of the yield protected certificates, and

Based on information provided annually by CitiMortgage with respect to the yield protected certificates, CitiMortgage will report annually to the holders of the yield protected certificates and to the IRS (as attachments to Form 1041 or other applicable form) their allocable shares of income and expense with respect to their right to receive payments under the yield maintenance agreement under the rules applicable to notional principal contracts, taking into account the portion of the original issue price of the yield protected

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certificates allocable to their right to receive payments under the yield maintenance agreement, and treating each holder of yield protected certificates as if it were an original holder, and

CitiMortgage will not vary the investment of the holders of the yield protected certificates to take advantage of variations in market rates of interest to improve their rates of return.

Notices should be sent:

To the Trustee at its corporate trust office at One Federal Street, 3rd Floor, Boston, Massachusetts 02110, Attention: Corporate Trust Services.

To CMSI at Citicorp Mortgage Securities, Inc., 1000 Technology Drive, O’Fallon, Missouri 63368, Attention: Daniel P. Hoffman.

To CitiMortgage at CitiMortgage, Inc., 1000 Technology Drive, O’Fallon, Missouri 63368, Attention: Daniel P. Hoffman.

To S&P at 55 Water Street, 41st Floor, New York, New York 10041, Attention: RMBS Surveillance.

To Moody’s at 99 Church Street, New York, New York 10007.

To Fitch at Residential Mortgage Pass-Through Monitoring, Fitch Ratings, One State Street Plaza, 30th Floor, New York, New York 10004.

To Citibank, N.A. at (a) for certificate transfer and presentment of certificates for final distribution, at 111 Wall Street, 15th floor, New York, NY 1005, Attention: 15th floor window, and (b) for all other purposes, at 388 Greenwich Street, 14th Floor, New York, NY 10013, Attention: Agency and Trust, CMSI.

To the Mortgage Document Custodian at Citibank, N.A., 5280 Corporate Drive, M/C 0005, Frederick, Maryland 21703, Attention: Loretta Badgett.

To any Insurer, at the address given for the Insurer in the first paragraph of "Insured classes" above.

The Paying Agent, any Insurer, CMSI and CitiMortgage may each change their address for notices by written notice to the others. The Trustee may change its corporate trust office by written notice to CMSI, CitiMortgage, any Insurer, and all certificate holders.

Notwithstanding anything to the contrary herein, any and all email communications (both text and attachments) by or from the Paying Agent that the Paying Agent in its sole discretion deems to contain confidential, proprietary, and/or sensitive information shall be encrypted. The recipient (the Email Recipient ) of the email communication will be required to complete a one-time registration process. Instructions on how to register and/or retrieve an encrypted message will be included in the first secure email sent by the Paying Agent to the Email Recipient. Additional information and assistance on using the Paying Agent’s encryption technology can be found at the Paying Agent’s website www.citigroup.com/-citigroup/-citizen/privacy/email.htm or by calling (866) 535-2504 (in the U.S.) or (904) 954-6181 at any time.

The initial Depository for the certificate and servicing accounts for the mortgage loans will be Citibank, N.A. 

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STANDARD TERMS

1   Definitions and usages

1.1   Defined terms

In this agreement, the following words and phrases have the following meanings:

accrual termination day : For an accrual class, the earlier of (1) the first distribution day on which the principal balance of each of its accrual directed classes on the preceding day is zero, or (2) the subordination depletion date.

affiliate : For a specified person, any other person that controls, is controlled by or is under common control with the specified person. In this definition, "control" of a specified person means the power to direct the management and policies of the person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise; and the terms "controlling" and "controlled" have correlative meanings.

affiliated servicing fee rate : 0.25% per annum. The monthly affiliated servicing fee rate is one-twelfth of the affiliated servicing fee rate.

aggregate outstanding advances : For a determination date, the aggregate of net servicing account advances, net voluntary advances, net Paying Agent advances and advance account advances made from the cut-off date to the determination date, plus any uncommitted cash advances to be made on the next distribution day.

appraisal : For a mortgage loan, the appraisal conducted in connection with the origination of the mortgage loan, whether originated upon the purchase of the related mortgaged property or in connection with a refinancing.

Authorized Officer : For CitiMortgage or CMSI, the Chairman of the Board of Directors, the President, any Executive Vice President, Senior Vice President, Vice President, Assistant Vice President, Controller, Assistant Controller, Secretary, Assistant Secretary, Treasurer or Assistant Treasurer, or any other natural person designated in an officer’s certificate signed by any of the foregoing officers and furnished to the Trustee and, solely in the case of a statement given pursuant to section 3.22, any Servicing Officer.

Bankruptcy Code : The United States Bankruptcy Code of 1978.

bankruptcy coverage termination date : If there is a bankruptcy loss limit, the distribution day on which the bankruptcy loss limit has been reduced to zero or a negative number (or the subordination depletion date, if earlier).

bankruptcy loss : For a mortgage loan, (1) a debt service reduction or (2) a deficient valuation, unless , in either case, CitiMortgage has notified the Trustee that CitiMortgage is diligently pursuing any remedies that may exist in connection with the representations and warranties made regarding the related mortgage loan and either (A) the related mortgage loan is not in default with regard to payments due thereunder, or (B) delinquent payments of principal and interest under the related mortgage loan, and any premiums on any applicable hazard insurance policy and any related escrow payments for the mortgage loan, are being advanced on a current basis without giving effect to any debt service reduction.

bankruptcy loss limit : If an initial bankruptcy loss limit is stated in the Series Terms, for a distribution day, the initial bankruptcy loss limit minus the aggregate amount of bankruptcy losses since the cut-off date. The bankruptcy loss limit may be further reduced by CitiMortgage (including accelerating the manner in which such coverage is reduced) provided that prior to

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the reduction, each rating agency confirms in writing to CitiMortgage (with a copy to the Trustee) that the reduction will not adversely affect the rating agency’s then-current rating of the certificates.

beneficial owner : For a certificate held by a Clearing Agency, the person who is the beneficial owner of the certificate as reflected on the Clearing Agency’s books or on the books of a person maintaining an account with the Clearing Agency (directly or as an Indirect Participant, in accordance with the Clearing Agency’s rules).

business day : Any day other than a Saturday, a Sunday or a day on which banking institutions in New York, New York or in the cities where the Trustee, the Paying Agent, CMSI, CitiMortgage, any Insurer (but only to the extent that the Insurer is required under this agreement to make or receive a payment on that day), any delegated servicers, and (but only if the third-party servicer is depositing funds received on third-party mortgage loans with CitiMortgage or the Paying Agent on that day) the third-party servicer is located are authorized or obligated by law or executive order to be closed or, in the case of a distribution day and if there are book-entry certificates, any day on which the relevant Clearing Agency is closed. For purposes of determining LIBOR for any LIBOR classes, a business day is a day on which banks in London and New York are open for the transaction of international business.

buydown account : The deposit account or accounts, which may bear interest, created and maintained in the name of the Trustee for the benefit of the mortgagors, subject to the rights of the Trustee pursuant to the buydown subsidy agreements.

buydown funds : Funds contributed at origination by the seller or buyer of a property subject to a buydown mortgage loan, or by any other source, plus interest earned thereon, in order to reduce the payments required from the mortgagor for a specified period in specified amounts.

buydown mortgage loan : Any mortgage loan for which, pursuant to a buydown subsidy agreement, (i) the mortgagor pays less than the full monthly payments specified in the mortgage note for a specified period, and (ii) the difference between the payments required under the buydown subsidy agreement and the mortgage note is provided from buydown funds.

buydown subsidy agreement : The agreement relating to a buydown mortgage loan pursuant to which an Originator may apply the buydown funds to a mortgagor’s payments.

certificate holder or holder : The person in whose name a certificate is registered in the Certificate Register.

Citibank banking affiliate : An affiliate of Citibank, N.A. that is either (i) a federal savings and loan association duly organized, validly existing and in good standing under the federal banking laws, (ii) an institution duly organized, validly existing and in good standing under the applicable banking laws of any state, or (iii) a national banking association duly organized, validly existing and in good standing under the federal banking laws.

class : For certificates, any certificates designated as a class in the Series Terms, for any class L or class P regular interests, the regular interests in the constituent REMIC designated as such in "REMIC provisions" above, and for residual certificates, all residual certificates having the same class designation. A "class" will be understood not to include a residual class of certificates unless otherwise expressly stated.

class percentage : For one or more classes, the ratio of the aggregate of the principal

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balances of the classes to the aggregate of the principal balances of all classes of the series, expressed as a percentage.

classes A-x through A-y : For a positive integer x and a greater integer y , each class A- z for all integers z from x through y , inclusive. Example : "classes A-3 through A-5" means each of classes A-3, A-4, and A-5. If a class is designated with an integer and letter pair, then such class follows the class with the same integer x and precedes the class of the next greater integer y . Example : "classes A-3 through A-5" means, if there are classes A-4A and A-4B, each of classes A-3, A-4, A-4A, A-4B, and A-5.

classes B-x through B-y : For a positive integer x and any greater integer y , each class B- z for all integers z from x through y , inclusive. Example : "classes B-3 through B-5" means each of classes B-3, B-4 and B-5.

Clearing Agency : An organization registered as a "clearing agency" pursuant to Section 17A of the Exchange Act. The initial Clearing Agency will be The Depository Trust Company.

Clearing Agency Participant : A broker, dealer, bank other financial institution or other person for whom a Clearing Agency effects book-entry transfers and pledges of securities deposited with the Clearing Agency.

collected servicing fee on a mortgage loan: For any month, the excess of the interest payment received on the mortgage loan for the month (including accrued interest due but not received from liquidation or insurance proceeds for liquidated loans) over the amount of interest on the mortgage loan for the month at the pass-through rate, up to the servicing fee CitiMortgage is permitted to retain under this agreement.

debt service reduction : For a mortgage loan, a reduction in the scheduled monthly loan payment for the mortgage loan by a court of competent jurisdiction in a proceeding under the Bankruptcy Code or any similar state law, except a reduction that would constitute a deficient valuation. If the court proceeding results in an increase in the scheduled payment for a month (for example, a final balloon payment or a payment in a month after the originally scheduled maturity of the mortgage loan), the increased payment will be considered a scheduled payment and not a debt service reduction.

Example: Suppose a homeowner has a mortgage loan with an outstanding principal balance of $50,000 and an interest rate of 7%. The loan has 10 years to run. The homeowner files for bankruptcy, and the bankruptcy court (1) reduces the outstanding principal balance to $40,000, (2) reduces the interest rate to 6%, and (3) stretches the payments out to 20 years. Then

·   the $10,000 reduction in principal owed is a bankruptcy loss, and

·   the difference between the monthly payment the homeowner would have made on the remaining $40,000 at the original interest rate and maturity, and the monthly payment the homeowner is now required to make on the new lower interest rate and extended maturity, is a debt service reduction, and

·   payments in the final 10 years (that is, after the originally scheduled maturity) will be scheduled payments.

deficient valuation : For a mortgage loan, a valuation by a court of competent jurisdiction of the mortgaged property in an amount less than the then-outstanding indebtedness under the mortgage loan, or a reduction in the scheduled monthly principal payment that results in a permanent forgiveness of principal, which valuation or reduction results from a proceeding under the Bankruptcy Code or any similar state law.

delegated servicer : A person or persons, including a special servicer, to whom CitiMortgage delegates some or all of its

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servicing obligations pursuant to section 4.5.

Depository : The bank or banks or savings and loan association or associations or trust company or companies (which may be the Trustee or which may be Citibank, N.A. or a Citibank banking affiliate ) at which the certificate account, buydown account, escrow account, custodial account for P&I and servicing account are established or maintained pursuant to section 3.2, 3.3 or 3.3. Each Depository must meet the requirements of section 11.1.

determination date : For each distribution day, the close of business on the 18th day (or, if that day is not a business day, the preceding business day) of the month in which the distribution day occurs.

discount loan : A mortgage loan that has a pass-through rate less than the target rate.

Eligible Account : Either

(A) a segregated account or accounts maintained at Citibank, N.A. or a Citibank banking affiliate, provided that the short-term unsecured debt obligations of Citibank, N.A. or the Citibank banking affiliate are rated at least "A-1+" by S&P if S&P is a rating agency, "F-l" by Fitch if Fitch is a rating agency, and "P-1" by Moody’s if Moody’s is a rating agency, or

(B) a segregated account or accounts maintained with an institution

·   whose deposits are insured by the FDIC,

·   the unsecured and uncollateralized debt obligations of which are rated at least "AA" by S&P if S&P is a rating agency, "AA" by Fitch if Fitch is a rating agency, and "Aa" by Moody’s if Moody’s is a rating agency,

·   that has a short term rating of at least "A-1+" by S&P if S&P is a rating agency, "F-1" by Fitch if Fitch is a rating agency, and "P-1" by Moody’s if Moody’s is a rating agency, and

·   is either (i) a federal savings and loan association duly organized, validly existing and in good standing under the federal banking laws, (ii) an institution duly organized, validly existing and in good standing under the applicable banking laws of any state, (iii) a national banking association duly organized, validly existing and in good standing under the federal banking laws and (iv) a principal subsidiary of a bank holding company, or

(C) a trust account (which will be a "special deposit account") maintained with the trust department of a federal or state chartered depository institution or of a trust company, having capital and surplus of not less than $50 million, acting in its fiduciary capacity.

Any Eligible Account maintained with the Trustee will conform to the preceding clause (C).

ERISA : The Employee Retirement Income Security Act of 1974.

ERISA Restricted Certificates : The B-4, B-5 and B-6 certificates.

Exchange Ac t: The Securities Exchange Act of 1934.

extraordinary event : Any of the following events: (i) hostile or warlike action in time of peace or war; (ii) the use of any weapon of war employing atomic fission or radioactive force whether in time of peace or war; or (iii) insurrection, rebellion, revolution, civil war or any usurped power or action taken by any governmental authority in preventing such occurrences (but not including looting or rioting occurring not in time of war).

FDIC : The Federal Deposit Insurance Corporation.

Fitch : Fitch Ratings.

fraud loss limit : If an initial fraud loss limit is stated in the Series Terms, for a distribution day,

(X) prior to the second anniversary of the cut-off date, the initial fraud loss limit

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minus the aggregate amount of fraud losses since the cut-off date, and

(Y) from the second through fifth anniversary of the cut-off date, (1) the lesser of (a) the fraud loss limit as of the most recent anniversary of the cut-off date and (b) 0.50% of the aggregate scheduled principal balance of all the mortgage loans as of the most recent anniversary of the cut-off date, minus (2) the aggregate amount of fraud losses since the most recent anniversary of the cut-off date.

After the fifth anniversary of the cut-off date the fraud loss limit will be zero.

fraud loss : A liquidated loan loss as to which there was fraud in the origination of the mortgage loan.

GIC : A guaranteed investment contract or surety bond.

GNMA : the Government National Mortgage Association.

group : In a multiple-pool series, the classes related to a pool; in a single-pool series, all the classes.

group target-rate class percentage : For one or more target-rate classes of a group, the ratio of the classes’ principal balance to the principal balance of all target-rate classes of the group, expressed as a percentage. For a single pool series, the group target-rate class percentage is the same as the target-rate class percentage.

Guide : The CitiMortgage, Inc. Servicing Guide, being the manual relating to CitiMortgage’s mortgage loan purchase program, as revised or supplemented from time to time.

high-cost mortgage loan : A "high cost loan," "high-rate, high-fee mortgage," "covered loan," or similar loan under any predatory lending law, if the law contains provisions that may result in liability of the Trust Fund as a purchaser or assignee of the loan.

holder : Has the same meaning as "certificate holder."

hypothetical mortgage loan : A non-existent mortgage loan that, combined with one or more other hypothetical mortgage loans, would have the same interest and principal payments as an actual mortgage loan.

Example: A mortgage loan having a principal balance of $100,000 and a pass-through rate of 8% could be divided into two hypothetical mortgage loans, the first having a $100,000 principal balance and a pass-through rate of 7% per annum, and the second an IO loan having a $100,000 principal balance and a pass-through rate of 1% per annum. References to the hypothetical mortgage loans in the target-rate strip will include those actual mortgage loans whose pass-through rates equal the target rate.

independent accountants : Accountants who are "independent" within the meaning of Rule 2-01(b) of the Securities and Exchange Commission’s Regulation S-X under the Exchange Act.

Indirect Participant : An organization that participates in the Clearing Agency by clearing through or by maintaining a custodial account with a Participant.

initial : As applied to a principal or notional balance, target-rate class percentage, or subordination level, means the principal or notional balance, target-rate class percentage, or subordination level as of the cut-off date.

insurance proceeds : Proceeds of

·   a primary mortgage insurance policy,

·   a hazard insurance policy to the extent not applied to restore the mortgaged property or released to the mortgagor in accordance with CitiMortgage’s normal servicing procedures or, for a third-party servicer, the Guide, and

·   any other insurance policy or bond relating to the mortgage loans or their servicing.

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Internal Revenue Code : The Internal Revenue Code of 1986.

investment account : The certificate account (but only if so stated in the Series Terms) and any other account or any portion thereof that consists of cash or Eligible Investments.

Investment Income : Any and all investment income and gains, net of any losses, actually received on the investment of funds on deposit in all investment accounts.

IO class : A class that has a certificate rate but no principal balance, receives interest distributions on its notional balance, but does not receive principal distributions.

IO loan : A mortgage loan having only a "notional balance." Such a mortgage loan would pay interest (usually at a variable rate) on its notional balance, but would not pay principal.

IO strip : The ratio-stripped IO loans for all the premium loans.

liquidated loan : A mortgage loan for which

·   the related mortgaged property has been acquired, liquidated or foreclosed, and the relevant servicer determines that all liquidation proceeds it expects to recover have been recovered, or

·   the related mortgaged property is retained or sold by the mortgagor, and the relevant servicer has accepted payment from the mortgagor in consideration for the release of the mortgage in an amount that is less than the outstanding principal balance of the mortgage loan as a result of a determination by the relevant servicer that the potential liquidation expenses for the mortgage loan would exceed the amount by which the cash portion of such payment is less than the outstanding principal balance of the mortgage loan.

liquidated loan loss : For a distribution day, the aggregate losses for each mortgage loan that became a liquidated loan prior to the first day of the month that contains the distribution day, which for each such liquidated loan will equal the excess of

·   (A) the unpaid principal balance of the mortgage loan on the first day of the preceding month, plus (B) accrued interest in accordance with the amortization schedule at the time applicable to the mortgage loan at the applicable mortgage note rate from the first day of the month as to which interest was last paid on the mortgage loan through the last day of the month in which the mortgage loan became a liquidated loan, over

·   the net liquidation proceeds for the mortgage loan.

Each liquidated loan loss will have an interest portion and a principal portion. If net liquidation proceeds for the mortgage loan exceed the accrued interest described in clause (B) above, the interest portion of the liquidated loan loss will be zero; otherwise, the interest portion of the liquidated loan loss will be the excess of the accrued interest described in clause (B) above over such net liquidation proceeds. The principal portion of a liquidated loan loss will equal the liquidated loan loss minus the interest portion of the liquidated loan loss.

liquidation expenses : For a liquidated loan, out-of-pocket expenses paid or incurred by or for the account of the relevant servicer or the Trust Fund for (a) property protection expenses, (b) property sales expenses, (c) foreclosure costs, including court costs and reasonable attorneys’ fees, (d) similar expenses reasonably paid or incurred in connection with the liquidation of the liquidated loan, (e) servicing fees not previously paid on the liquidated loan, and (f) any tax imposed on the Trust Fund with respect to a liquidated loan or property received by deed in lieu of foreclosure.

liquidation proceeds : For a period, the amounts received by the relevant servicer in

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connection with the liquidation of a liquidated loan, whether through judicial or non-judicial foreclosure, proceeds of insurance policies, condemnation proceeds, proceeds of a deficiency action (less amounts retained by CitiMortgage pursuant to section 3.12), or otherwise, including payments received from the mortgagor for the liquidated loan, other than amounts required to be paid to the mortgagor pursuant to the terms of the liquidated loan or to be applied otherwise pursuant to law.

loss recovery : For a liquidated loan, any amounts received on the liquidated loan (net of expenses on the liquidated loan) for any month after the month in which the mortgage loan becomes a liquidated loan, that are not applied to the reduction of aggregate outstanding advances for the liquidated loan.

master servicing fee : The amount payable to CitiMortgage pursuant to section 3.7.

master servicing fee rate : The per annum rate agreed between CitiMortgage and a third-party servicer for calculating the master servicing fee. The monthly master servicing fee rate will be one-twelfth of the master servicing fee rate.

month : A calendar month.

Moody’s : Moody’s Investors Service, Inc.

mortgage : For a mortgage loan, the mortgage or deed of trust creating a first lien on and an interest (a) for a mortgage loan relating to a cooperative apartment in a cooperative housing corporation, in the mortgagor’s interest therein securing a mortgage note, and (b) for other cases, in real property securing a mortgage note.

mortgage documents : All documents contained in the mortgage file.

mortgage file : The mortgage documents listed in section 2.1 pertaining to a particular mortgage loan and any additional documents required to be added to such documents pursuant to this agreement.

mortgage loan : At any time, the indebtedness of a mortgagor evidenced by a mortgage note that is secured by real property (or shares evidencing ownership interest in a cooperative apartment in a cooperative housing corporation) and that is sold and assigned to the Trustee and held at such time in the Trust Fund pursuant to this agreement, the mortgage loans originally so held being identified in the mortgage loan schedule.

mortgage loan schedule : The list of mortgage loans transferred to the Trustee as part of the Trust Fund, attached as exhibit B, or separately delivered, in physical or electronic form, to the Trustee.

mortgage note : For a mortgage loan, the promissory note or other evidence of indebtedness of the mortgagor.

Mortgage Note Custodian : The Mortgage Document Custodian is also designated by CMSI as the Mortgage Note Custodian. At any time that the rating agencies’ respective rating of Citigroup Inc.’s long-term senior debt is below the respective rating assigned by each such rating agency to the certificates, the Mortgage Note Custodian may not be an affiliate of CMSI.

mortgage note rate : For a mortgage loan, the annual rate per annum at which interest accrues on the mortgage loan.

mortgaged property : Any real property subject to a mortgage, or any cooperative apartment in a cooperative housing corporation.

mortgagor : The obligor on a mortgage note.

multiple-pool series : A series in which the mortgage loans are divided into two or more pools for purposes of allocations and distributions. Each series is either a single-pool series or a multiple-pool series.

net liquidation proceeds : For a period, the aggregate amount of liquidation proceeds for a liquidated loan, net of related

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liquidation expenses not previously recovered.

net REO proceeds : For a REO loan, REO proceeds net of any related expenses of the relevant servicer.

net Paying Agent advances : For a period, the amount (which may be negative) obtained by subtracting the amount of any reimbursements for Paying Agent advances received in the period from the aggregate amount of Paying Agent advances made in the period.

net voluntary advances : For a period, the amount (which may be negative) obtained by subtracting the amount of any reimbursements for voluntary advances received in the period from the aggregate amount of voluntary advances made in the period.

nonrecoverable advance : Any portion of a voluntary advance or Paying Agent advance previously made or proposed to be made in respect of a mortgage loan that has not been previously reimbursed to the relevant servicer or the Paying Agent and that, in the good faith judgment of such person, would not be ultimately recoverable from liquidation proceeds or other recoveries in respect of the related mortgage loan. Nonrecoverable advances also include any advance by CitiMortgage of part or all of the shortfall in interest collections on a mortgage loan due to the federal Servicemembers Civil Relief Act or any similar state legislation that cannot be recouped from later payments on the mortgage loan. The determination by such person that it has made a nonrecoverable advance or that any proposed advance, if made, would be a nonrecoverable advance, will be evidenced by a certification of a Servicing Officer delivered to the Trustee and the Paying Agent and detailing the basis for such determination, but any delay or failure to send such certification will not impair such person’s right to withhold or recover such advance.

non-subordinated losses : (1) Special hazard, fraud or bankruptcy losses that exceed the then-applicable limit for that type of loss, (2) realized losses from extraordinary events, and (3) interest shortfalls due to limitations on interest rates mandated by the federal Servicemembers Civil Relief Act or any comparable state laws.

non-supported prepayment interest shortfall : For a distribution day and a class (other than a PO class), the class’s proportionate share, based on interest accrued, of the sum of (1) for affiliated mortgage loans, the excess, if any, of the prepayment interest shortfalls on such mortgage loans for that distribution day over the amount deposited in the distribution account by CitiMortgage pursuant to section 3.4 in connection with prepayment interest shortfalls, and (2) for third-party mortgage loans, any excess of the prepayment interest shortfalls on such mortgage loans for that distribution day over the aggregate amount deposited in the certificate account in respect thereof by the applicable third-party servicers as required by section 3.4 and the Guide.

officer’s certificate : A certification signed by an Authorized Officer of CitiMortgage or CMSI and delivered to the Trustee or Paying Agent.

opinion of counsel : A written opinion of counsel, who (unless otherwise specified herein) may be counsel for, or an employee of, CMSI or an affiliate of CMSI, which counsel will be reasonably acceptable to the Trustee.

order of seniority : For the target-rate classes, the following order: the senior classes, followed by classes B-1, B-2, B-3, B-4, B-5 and B-6.

order of subordination : For the target-rate classes, the following order: classes B-6, B-5,

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B-4, B-3, B-2 and B-1, followed by the senior classes.

original value : For the mortgaged property underlying a mortgage loan, the lesser of

·   the sales price of the mortgaged property and

·   its appraisal value determined pursuant to an appraisal made in connection with origination of the mortgage loan, except that the original appraisal of the mortgaged property may be used for a refinanced mortgage loan the unpaid principal balance of which, after refinancing, does not exceed the unpaid principal balance of the original mortgage loan at the time of refinancing by an amount greater than the amount of the closing costs associated with the refinancing.

The original value of a mortgage loan is the original value of the mortgaged property underlying the mortgage loan plus the value of any other property securing the mortgage loan.

Originator : The affiliate or affiliates of CMSI, or the third-party originators, from which CMSI is acquiring the mortgage loans.

outstanding : (1) For certificates as of any date, all certificates previously authenticated and delivered under this agreement except:

(i) certificates that have been canceled by the Certificate Registrar or delivered to the Certificate Registrar for cancellation;

(ii) certificates for which money for a distribution in the necessary amount to reduce the principal balance to zero has been deposited with the Paying Agent in trust for the holders of such certificates; provided, however, that if a distribution in reduction of the principal balance of such certificates to zero will be made, notice of the distribution has been duly given pursuant to this agreement or provision therefor, satisfactory to the Trustee, has been made;

(iii) certificates in exchange for or in lieu of which other certificates have been authenticated and delivered pursuant to this agreement unless proof satisfactory to the Certificate Registrar is presented that any such certificates are held by a protected purchaser under Article 8 of the Uniform Commercial Code in effect in the applicable jurisdiction; and

(iv) certificates alleged to have been destroyed, lost or stolen for which replacement certificates have been issued as provided for in section 5.3 and authenticated and delivered pursuant to this agreement;

provided , however, that in determining whether the holders of the requisite percentage of the aggregate principal balance or percentage interest of any outstanding certificates or of the outstanding certificates of any one or more classes have given any request, demand, authorization, direction, notice, consent or waiver, such percentage will be based on the principal balance of such certificate and provided, further, certificates owned by CMSI or any other obligor upon the certificates or any affiliate of CMSI or such other obligor will be disregarded and deemed not to be outstanding, except that, in determining whether the Trustee will be protected in relying upon any such request, demand, authorization, direction, notice, consent, or waiver, only certificates which the Trustee knows to be so owned will be so disregarded and except that where CMSI or any other obligor upon the certificates or any affiliate of CMSI or such other obligor will be owner of 100% of the aggregate principal balance or percentage interest of any outstanding certificates, CMSI or such other obligor or affiliate will be permitted to give any request, demand, authorization,

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direction, notice, consent or waiver hereunder. Certificates so owned that have been pledged in good faith may be regarded as outstanding if the pledgee establishes to the satisfaction of the Trustee the pledgee’s right so to act with respect to such certificates and that the pledgee is not CMSI or any other obligor upon the certificates or any affiliate of CMSI or such other obligor.

(2) for a class for any day, a class with a non-zero principal balance or non-zero notional balance on that day, and

(3) for a mortgage loan, for the first day of a month, a mortgage loan that, prior to such first day, was not the subject of a principal prepayment in full, did not become a liquidated loan, and was not purchased pursuant to section 2.2 or 2.3.

Participant : A participating organization in the Clearing Agency.

pass-through rate : For a mortgage loan for any date or period, the applicable mortgage note rate, minus

Any regular monthly remittance of interest at the pass-through rate for a mortgage loan is based upon annual interest at that rate on the scheduled principal balance as of the first day of the month of the mortgage loan divided by twelve. Interest at the pass-through rate will be computed on the basis of a 360-day year, each month being assumed to have 30 days. The monthly pass-through rate will be one-twelfth of the pass-through rate.

(Any partial remittance of interest at such rate by reason of a full principal prepayment is based upon annual interest at that rate on the prepaid principal balance of the related mortgage loan, multiplied by a fraction the numerator of which is the actual number of days elapsed in the month of the prepayment to the date of the prepayment, and the denominator of which is 360. For affiliated mortgage loans, and some or all of the third-party mortgage loans, the mortgagor is not required to pay interest on a partial principal prepayment that is received during a month. The amounts required to be paid pursuant to section 3.4 are in addition to any interest payments made by mortgagors and passed through on full and partial prepayments.)

percentage interest : For a class of residual certificates, if the residual certificate has a principal balance as specified in the Series Terms, the ratio of the initial principal balance of the residual certificate to the aggregate initial principal balance of the entire class, expressed as a percentage; if the residual certificate does not have a principal balance, the portion represented by such residual certificate (expressed as a percentage) of the total ownership interest in the applicable constituent REMIC represented by all residual certificates of the class. For a certificate of an IO class, the ratio of the notional balance of the certificate to the aggregate notional balance of the entire class.

person : Any legal person, including any individual, corporation, partnership, joint venture, association, joint stock company, trust, unincorporated organization or government or any agency or political subdivision thereof.

PO class : A class that has a principal balance and receives principal distributions, but does not have a certificate rate and does not receive interest distributions.

PO loan : A mortgage loan that has a principal balance, but on which no interest is paid by the mortgagor.

PO strip : The ratio-stripped PO loans for all the discount loans.

pool : A pool of mortgage loans.

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pool distribution amount : For a distribution day and a mortgage loan pool, the funds eligible for distribution to the related classes on that distribution day, being all amounts deposited into the certificate account relating to that pool, but excluding the following:

(a)   uncommitted cash that will not be used on the distribution day for an uncommitted cash advance;

(b)   all permitted withdrawals from the certificate account pursuant to section 3.8; and

(c)   all income from Eligible Investments that are held in an investment account.

predatory lending law : The Georgia Fair Lending Act, the Maine Consumer Credit Code - Truth-in-Lending, the New Jersey Home Ownership Security Act of 2002, the New Mexico Home Loan Protection Act, the New York Predatory Lending Act, or any similar state, local or federal law that regulates high-cost mortgage loans.

Predecessor Certificates : For a particular certificate of a class, every previous certificate of that class evidencing all or a portion of the same principal balance, notional balance or percentage interest as that evidenced by the particular certificate; for the purpose of this definition, any certificate authenticated and delivered under section 5.3 in lieu of a lost, destroyed or stolen certificate will be deemed to evidence the same principal balance, notional balance or percentage interest, as the case may be, as the lost, destroyed or stolen certificate.

premium loan : A mortgage loan having a pass-through rate equal to or greater than the target rate.

prepayment interest shortfall : For a mortgage loan that was the subject of a principal prepayment applied during the preceding month, an amount equal to (1) one month of interest on the principal prepayment at the pass-through rate, less (2) the amount of any interest (adjusted to the pass-through rate) on the principal prepayment received from the mortgagor.

primary mortgage insurance certificate : The certificate of primary mortgage insurance relating to a particular mortgage loan to the extent initially set forth in the mortgage loan schedule.

principal prepayment : For a mortgage loan, a payment of principal on the mortgage loan that is received in advance of the date it is scheduled to be paid and that is not accompanied by an amount representing scheduled interest for any month subsequent to the month of prepayment, but excluding any proceeds of or advances on a liquidated loan.

private certificates : The residual certificates and certificates of classes B-4 through B-6 and, unless otherwise stated in the Series Terms, any ratio-stripped IO classes.

Proceeding : Any suit in equity, action at law or other judicial or administrative proceeding.

property protection expenses : For mortgage loans, expenses paid or incurred by or for the account of CitiMortgage or the Trust Fund in accordance with the related mortgages for (a) real estate property taxes and property repair, replacement protection and preservation expenses, and (b) similar expenses reasonably paid or incurred to preserve or protect the value of the mortgages.

Qualified GIC : A GIC, assigned to the Trustee or Paying Agent, or entered into by the Trustee or Paying Agent at the direction of CMSI, on or before the closing date, providing for the investment of funds insuring a minimum or fixed rate of return on investments of such funds, which contract or surety bond will

(a)   be an obligation of an insurance company, trust company, commercial bank

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(which may be Citibank, N.A. or a Citibank banking affiliate) or other entity whose credit standing is confirmed in writing as acceptable by each rating agency;

(b)   provide that the Trustee or the Paying Agent may exercise all of the rights of CMSI under such contract or surety bond without the necessity of the taking of any action by CMSI;

(c)   provide that if at any time (subject to the second proviso of this section (c)) the then current credit standing of the obligor under such guaranteed investment contract is such that continued investment pursuant to such contract of funds included in the Trust Fund would result in a downgrading of any rating of any class of the certificates, the Trustee or the Paying Agent may terminate such contract and be entitled to the return of all funds previously invested thereunder, together with accrued interest thereon at the interest rate provided under such contract through the date of delivery of such funds to the Trustee or the Paying Agent, provided that the Trustee or the Paying Agent will not be charged with knowledge of any such potential downgrading unless it will have received written notice of such potentiality from the provider of the GIC which must be obligated to give such notice at least once per year; provided, further, that upon any such event CMSI, by written notice to the Trustee or the Paying Agent, may replace such contract with a substitute GIC having substantially the same terms (including without limitation a rate of return at least as high as the contract being replaced) so long as such substitute contract has an obligor with a credit standing no less than the credit standing of the obligor under the contract to be replaced at the time the contract was executed and such fact is certified by CMSI to the Trustee or the Paying Agent;

(d)   provide that the Trustee’s interest therein will be transferable to any successor trustee hereunder;

(e)   provide that the funds invested thereunder and accrued interest thereon be available not later than the day prior to any distribution day on which such funds may be required for distribution hereunder; and

(f)   meet such other standards as may be specified in the Series Terms.

Qualified Nominee : A person (who may not be CMSI or an affiliate of CMSI) in whose name Eligible Investments held by the Trustee or Paying Agent may be registered as nominee of the Trustee or the Paying Agent in lieu of registration in the name of the Trustee or the Paying Agent, provided that the following conditions will be satisfied in connection with such registration:

(a)   the instruments governing the creation and operation of the nominee provide that neither the nominee nor any owner of an interest in the nominee (other than the Trustee or the Paying Agent) will have any interest, beneficial or otherwise, in any Eligible Investments held in the name of the nominee, except for the purpose of transferring and holding legal title thereto;

(b)   the nominee and the Trustee or the Paying Agent have entered into a binding agreement in substantially the form to be provided by CMSI establishing that any Eligible Investments held in the name of the nominee are to be held by the nominee as agent (other than commission agent or broker) or nominee for the account of the Trustee; and

(c)   in connection with the registration of any Eligible Investment in the name of the nominee, all requirements under applicable governmental regulations necessary to effect a valid registration of transfer of such Eligible Investment are complied with as evidenced to the Trustee and the Paying

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Agent upon its request by an opinion of counsel.

ratio-stripped IO class : An IO class with an initial notional balance equal to the initial notional balance of one or more IO strips, and that receives interest distributions solely from distribution on those strips.

ratio-stripped IO loan : For any premium loan with a pass-through rate greater than the target rate, a single hypothetical IO loan that, combined with a single hypothetical target-rate loan, has the same interest and principal payments as the premium loan.

Example: For a premium loan with a $100,000 principal balance and a pass-through rate 1% per annum greater than the target rate, the (hypothetical) ratio-stripped IO loan will have a notional balance of $100,000 and a pass-through rate of 1% per annum, and the (hypothetical) target-rate loan will have a principal balance of $100,000 and a pass-through rate equal to the target rate.

ratio-stripped PO class : A PO class whose initial principal balance equals the initial principal balance of one or more PO strips (rounded down to the nearest whole dollar), and that receives principal distributions solely from distribution on those strips, or from reimbursements from subordinated classes.

ratio-stripped PO loan : For any discount loan, a single hypothetical PO loan that, combined with a single hypothetical target-rate loan, has the same interest and principal payments as the original discount loan.

Example: For a discount loan with a $100,000 principal balance and a pass-through rate 1% per annum less than the target rate of 5% per annum, the (hypothetical) ratio-stripped PO loan will have a principal balance of $20,000 and a pass-through rate of 0%, and the (hypothetical) target-rate loan will have a principal balance of $80,000 and a pass-through rate equal to the target rate.

realized losses : For a distribution day, liquidated loan losses (including special hazard losses and fraud losses) and bankruptcy losses incurred in the preceding month. For a realized loss consisting of a liquidated loan loss, the interest and principal portions of the realized loss will equal the interest and principal portions of the liquidated loan loss.

record date : For a distribution day, the close of business on (a) for a LIBOR class, the last day (whether or not a business day) of its last LIBOR accrual period preceding the distribution day, and (b) for any other class, the last day of the preceding month.

relevant servicer : CitiMortgage or a third-party servicer, as the context requires.

REMIC : A "real estate mortgage investment conduit" within the meaning of Internal Revenue Code Section 860D. References to the "REMIC" are to the constituent REMICs constituted by the Trust Fund.

REMIC Provisions : The provisions of the federal income tax law relating to REMICs, which appear at Sections 860A through 860G of the Internal Revenue Code.

REO loan : A mortgage loan that is not a liquidated loan and as to which the related mortgaged property is held as part of the Trust Fund.

REO proceeds : Proceeds, net of any related expenses, received in respect of any REO loan (including, without limitation, proceeds from the rental of the related mortgaged property).

REO property : A mortgaged property acquired by the Trust Fund through foreclosure or deed-in-lieu of foreclosure in connection with a defaulted mortgage loan or otherwise treated as having been acquired pursuant to the REMIC Provisions.

Required Amount of Certificates : (i) 2/3 or more of the aggregate voting interest of the outstanding certificates, if affected by the

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occurrence of an Event of Default and (ii) 2/3 or more of the aggregate outstanding percentage interest of the residual certificates, if affected by such an Event of Default.

Responsible Officer of the Trustee means an officer who is employed in the Corporate Trust Department or a similar group for the Trustee with direct responsibility for the administration of this agreement.

S&P : Standard and Poor’s Ratings Services, a division of The McGraw- Hill Companies, Inc.

scheduled monthly loan payment : For a mortgage loan (including a REO loan) and a distribution day, the payment of principal and interest due on the first day of the month in which the distribution day occurs in accordance with the amortization schedule applicable to the mortgage loan at that time (after adjustment for any partial principal prepayments or deficient valuations occurring prior to such first day of the month but before any adjustment to such amortization schedule other than deficient valuations by reason of any bankruptcy, or similar proceeding or any moratorium or similar waiver or grace period).

scheduled principal balance : For one or more mortgage loans on a date, the initial principal balance of the loans, less the sum of (a) the aggregate of the principal portion of all scheduled monthly loan payments required to be made on the loans on or before the first day of the month in which the date falls (whether or not received), provided that after the bankruptcy coverage termination date, the scheduled principal balance will not be reduced by the principal portion of any debt service reductions, and (b) any principal prepayments on the loans received or posted before the close of business on the last business day of the preceding month.

scheduled principal payments : For one or more mortgage loans for a distribution day, the principal portion of the scheduled monthly loan payments on the loans for the distribution day.

scheduled servicing fee : For any month, a fee equal to

·   for each affiliated mortgage loan, the scheduled principal balance of the mortgage loan as of the close of business on the last day of the preceding month, multiplied by the monthly affiliated servicing fee rate, and

·   for each third-party mortgage loan, the scheduled principal balance of the mortgage loan as of the close of business on the first day of the month, multiplied by the relevant monthly third-party servicing fee rate.

Securities Act : The Securities Act of 1933.

senior to : A target-rate class is senior to another target-rate class if it is ranked above it in order of seniority.

Servicing Officer : Any officer of CitiMortgage, a delegated servicer or a third-party servicer involved in, or responsible for, the administration and servicing of the Trust Fund whose name appears on a list of servicing officers attached to an officer’s certificate furnished to the Trustee by CitiMortgage, as such list may from time to time be amended.

single certificate : A single certificate evidences (a) for a residual certificate, 1% percentage interest, (b) for a certificate of an IO class, $1,000 initial notional balance, and (c) for a certificate of any other class, $1,000 initial principal balance.

single-pool series . A series in which the mortgage loans are not divided into two or more pools for purposes of allocations and distributions. Each series is either a single-pool series or a multiple-pool series.

special hazard loss : (i) A liquidated loan loss suffered by a mortgaged property on account of direct physical loss, exclusive of (a) any loss covered by a hazard policy or a

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flood insurance policy maintained for the mortgaged property pursuant to section 3.11, and (b) any loss caused by or resulting from:

(1)   normal wear and tear;

(2)   infidelity, conversion or other dishonest act on the part of the Trustee, CitiMortgage or any of their agents, employees or delegees; or

(3)   errors in design, faulty workmanship or faulty materials, unless the collapse of the property or a part thereof ensues; or

(ii) a liquidated loan loss suffered by the Trust Fund arising from or related to the presence or suspected presence of hazardous wastes or hazardous substances on a mortgaged property, unless the loss to a mortgaged property is covered by a hazard policy or a flood insurance policy maintained for the mortgaged property pursuant to section 3.11.

special hazard loss limit : If an initial special hazard loss limit is stated in the Series Terms, for a distribution day, the initial special hazard loss limit minus the sum of (i) the aggregate amount of special hazard losses and (ii) the Adjustment Amount (as defined below) as most recently calculated. For each anniversary of the cut-off date, the Adjustment Amount will be the excess of the amount calculated in accordance with the preceding sentence (without giving effect to the deduction of the Adjustment Amount for such anniversary) over the greater of (A) the product of the special hazard percentage for such anniversary multiplied by the aggregate scheduled principal balance of all the mortgage loans on the distribution day immediately preceding such anniversary and (B) twice the scheduled principal balance of the mortgage loan in the Trust Fund which has the largest scheduled principal balance on the distribution day immediately preceding such anniversary.

special hazard percentage : As of each anniversary of the cut-off date, the greater of (i) 1% and (ii) the largest percentage obtained by dividing the aggregate scheduled principal balances (as of the immediately preceding distribution day) of the mortgage loans secured by mortgaged properties located in a single, five-digit ZIP code area in the State of California by the aggregate scheduled principal balance of all the mortgage loans as of such anniversary.

subordinated losses : Realized losses other than non-subordinated losses.

subordinate to : A target-rate class is subordinate to another target-rate class if it is ranked below it in order of seniority.

subordination depletion date : The first distribution day for which the principal balance of the subordinated classes on the preceding day is zero.

target-rate class percentage : For one or more target-rate classes, the ratio of the classes’ principal balance to the principal balance of all target-rate classes, expressed as a percentage.

target-rate loan : For any mortgage loan, a single hypothetical mortgage loan that has a pass-through rate equal to the target rate, and

(i) if the mortgage loan has a pass-through rate equal to or greater than the target rate, has the same principal balance as the mortgage loan, and

(ii) if the mortgage loan is a discount loan, has a principal balance equal to the product of (A) the principal balance of the mortgage loan and (B) the ratio of the pass-through rate for the mortgage loan to the target-rate.

target-rate strip : The mortgage loan pool formed of the target-rate loans for all the mortgage loans.

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third-party servicing fee : For any month, a fee for each third-party mortgage loan equal to the lesser of (a) the scheduled principal balance of the mortgage loan as of the close of business on the first day of the month, multiplied by the relevant monthly third-party servicing fee rate, and (b) the excess of the interest payment received on the mortgage loan for the month (including interest payments included in liquidation or insurance proceeds) over the amount of the interest payment to be deposited in the certificate account.

third-party servicing fee rate : For a third-party mortgage loan other than a specially serviced mortgage loan, the per annum rate specified as such on schedule B-TP to exhibit B under the heading "Sub Fee," reduced (but not below zero) by any applicable master servicing fee rate, and for a specially serviced mortgage loan, the per annum servicing fee rate for the special servicer provided for in or pursuant to the special servicing agreement. The monthly third-party servicing fee rate will be one-twelfth of the relevant third-party servicing fee rate.

Transfer Instrument : A deed transferring an interest in property subject to a mortgage.

Trust Fund : The corpus of the trust created by this agreement, consisting of the mortgage loans, the certificate account, any pooling, lower-tier, or upper-tier REMIC account, REO property and the primary mortgage insurance certificates, any other insurance policies for the mortgage loans, any retail reserve fund and the rights of the Trustee under any reserve fund and any certificate insurance policy.

uncommitted cash : For a distribution day, any cash in the certificate account representing principal prepayments posted or liquidation proceeds deposited on or after the first day of the month immediately preceding such distribution day and all related payments of interest and all payments which represent early receipt of scheduled payments of principal and interest due on a date or dates subsequent to such first day of the month.

unscheduled principal payments : For one or more mortgage loans for a distribution day, the sum of

·   all principal prepayments on the mortgage loans received by CitiMortgage or a third-party servicer during the month preceding the distribution day, up to the scheduled principal balance, in each case, of the mortgage loan,

·   the greater of (1) aggregate net liquidation proceeds from any of the mortgage loans that became a Liquidated Loan during the month preceding such distribution day, minus (a) the portion of such proceeds representing interest, and (b) any unreimbursed advances of principal made by the CitiMortgage, a third-party servicer, or the Paying Agent on such mortgage loans, and (2) the aggregate scheduled principal balances of such mortgage loans for the distribution day, and

·   the scheduled principal balance of any of the mortgage loans that was repurchased by CMSI during such month pursuant to section 2.3, "Repurchase or substitution of mortgage loans" below.

U.S. person : A citizen or resident of the United States of America, a corporation or partnership (unless, in the case of a partnership, Treasury regulations are adopted that provide otherwise) created or organized in or under the laws of the United States of America, any state thereof or the District of Columbia, including an entity treated as a corporation or partnership for federal income tax purposes, an estate whose income is subject to U.S. federal income tax regardless of its source, or a trust if a court within the

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United States is able to exercise primary supervision over the administration of such trust, and one or more such U.S. persons have the authority to control all substantial decisions of such trust (or, to the extent provided in applicable Treasury regulations, certain trusts in existence on August 20, 1996 which are eligible to elect to be treated as U.S. persons).

1.2   Usages

In this agreement and the certificates, unless otherwise stated or the context otherwise clearly requires, the following usages apply:

·   "This agreement," "herein," "hereof" and words of similar import when used in this agreement will refer to this agreement.

·   In computing periods from a specified date to a later specified date, the words "from" and "commencing on" (and the like) mean "from and including," and the words "to," "until" and "ending on" (and the like) mean "to but excluding."

·   An action permitted under this agreement may be taken at any time and from time to time. Except as otherwise indicated, a permitted action may be taken in the actor’s sole discretion. References to a person’s taking action include the person’s refraining from action. Thus, a statement that a person "may take any action that … " means that a person may take or refrain from taking any action that ….

·   All indications of time of day mean New York City time.

·   "Including" means "including, but not limited to." "A or B" means "A or B or both."

·   References to an agreement (including this agreement) will refer to the agreement as amended at the relevant time.

·   References to numbered sections or paragraphs in this agreement will refer to sections or paragraphs of this agreement, and such section references will include all included sections. For example, a reference to section 6 will be to section 6 of this agreement, and also to sections 4.1, 4.2, etc .

·   References to an exhibit in this agreement will refer to all included numbered subdivisions of the exhibit. For example, references to exhibit A will also refer to subdivisions A-1, A-2, etc .

·   References to a statute include all regulations promulgated under or implementing the statute, as in effect at the relevant time. References to a specific provision of a statute includes successor provisions.

·   References to any governmental or quasi-governmental agency or authority will include any successor agency or authority.

·   Where a decimal appears that has been shortened, it will be rounded according to the usual rules; that is, if the decimal is only shown to x places, the last number (in the xth place) will be raised by one if the following number (in the x+1st place) is 5, 6, 7, 8 or 9.

1.3   Calculations respecting mortgage loans

(a)   In connection with all calculations required to be made pursuant to this agreement for remittances on any mortgage loan, any payments on the mortgage loans or any payments on any other assets included in a Trust Fund, the rules set forth in this section 1.2 will be applied.

(b)   Calculations for remittances on mortgage loans will be made on a mortgage-loan-by-mortgage-loan basis, based upon current information as to the terms of such mortgage loans and reports of payments received on such mortgage loans supplied to CitiMortgage by the person responsible for the servicing thereof and satisfying such requirement, if any, as may be set forth in section 3.

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(c)   Each remittance receivable on a mortgage loan will be assumed to be received on the first day of the month.

2   Transfer of mortgage loans and issuance of certificates; repurchase and substitution

2.1   Transfer of mortgage loans

(a) CMSI, as of the closing date, hereby transfers and assigns to the Trustee, without recourse, all of CMSI’s right, title and interest in and to

·   the mortgage loans, including all remittances received or receivable by CMSI on or with respect to the mortgage loans (other than payments of principal and interest due and payable on the mortgage loans, and principal prepayments thereon received, on or before the cut-off date), and

·   the proceeds of any title, primary mortgage, hazard or other insurance policies related to the mortgage loans.

Such transfer and assignment is absolute, is made in exchange for the certificates described in section 12, and is intended by the parties to be a sale. Nonetheless, to the extent such transfer is held not to be a sale under applicable law, it is intended that this agreement shall be a security agreement under applicable law, and CMSI shall be deemed to have granted to the Trustee, for the benefit of the certificate holders and any Insurer, a security interest in the Trust Fund, including the mortgage loans, mortgage notes and related documents. CMSI will, at its own expense, take any action reasonably requested by the Trustee to confirm, perfect, and protect the priority of, the security interest granted hereby, including the filing of Uniform Commercial Code financing statements in the appropriate jurisdictions.

CMSI will not transfer any other property to the Trust Fund except as expressly permitted by this agreement.

The Trustee acknowledges receipt of the documents and other property referred to in section 2.1, and declares that the Trustee will hold such documents and other property, including property yet to be received in the Trust Fund, in trust, upon the trusts herein set forth, for the benefit of all present and future certificate holders and any Insurer.

(b) The Trustee and CitiMortgage have entered into a Mortgage Document Custodial Agreement substantially in the form of exhibit C with the Mortgage Document Custodian named in section 12.1. The Mortgage Document Custodian will hold the mortgage documents in trust for the Trustee and the benefit of the Trustee, any Insurer and all present and future certificate holders. The Mortgage Document Custodian may be the Trustee, any affiliate of the Trustee, an affiliate of CMSI, or an independent entity.

The Trustee may at any time remove the initial or any successor Mortgage Document Custodian, and enter into a Mortgage Document Custodial Agreement substantially in the form of exhibit C hereto pursuant to which the Trustee appoints a successor Mortgage Document Custodian to hold the Mortgage Documents in trust for the Trustee and the benefit of the Trustee, all present and future certificate holders, and any Insurer, which Agreement may provide that the Mortgage Document Custodian shall conduct the review of each Mortgage File required under the first paragraph of section 2.3(b), except that, if the Mortgage Document Custodian so appointed is CMSI or an affiliate of CMSI, the Trustee may conduct such review.

(c) CMSI will on or before the closing date deliver to the Mortgage Document

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Custodian on behalf of the Trustee to be held in trust the following documents or instruments for each mortgage loan (other than mortgage loans secured by shares in a cooperative housing corporation) (except to the extent CMSI is complying with section 2.1(f)):

(i) The mortgage note, endorsed by manual or facsimile signature without recourse by the Originator or an affiliate of the Originator in blank or to the Trustee showing a complete chain of endorsements from the named payee to the Trustee or from the named payee to the affiliate of the Originator and from such affiliate to the Trustee, except that endorsement is not required where Mortgage Electronic Registration Systems, Inc. ( MERS ) is the named payee or the nominee of the named payee.

(ii) The original recorded mortgage, with evidence of recording thereon or a copy of the mortgage certified by the public recording office in those jurisdictions where the public recording office retains the original.

(iii) Any original assumption, modification, buydown or conversion-to-fixed-interest-rate agreement applicable to the mortgage.

(iv) An assignment from the Originator or an affiliate of the Originator to the Trustee in recordable form of the mortgage which may be included, where permitted by local law, in a blanket assignment or assignments of the mortgage to the Trustee, including any intervening assignments and showing a complete chain of title from the original mortgagee named under the mortgage to the Originator or such affiliate and to the Trustee, except that (x) a blanket assignment need not be in recordable form but shall be delivered with a limited power of attorney authorizing the Custodian, on behalf of the Trustee, to act for the Originator or such affiliate in preparing, executing, delivering and recording in the Trustee’s name any instruments for recording assignments of the related mortgages to the Trustee, (y) if the mortgage is registered with MERS, only assignments from the origination of the mortgage to its assignment to MERS will be required, and (z) if the mortgage was originated with MERS as the original mortgagee (a "MOM loan"), no interim assignment will be required.

(v) The original or a copy of the title insurance policy (which may be a certificate or a short form policy relating to a master policy of title insurance) pertaining to the mortgaged property, or in the event such original title policy is unavailable, a copy of the preliminary title report and the lender’s recording instructions, with the original to be delivered within 180 days of the closing date or other evidence of title.

(vi) Any related primary mortgage insurance certificate and related policy or a copy thereof.

(d) CMSI will on or before the closing date deliver to the Mortgage Document Custodian on behalf of the Trustee to be held in trust the following documents or instruments for each mortgage loan secured by shares in a cooperative housing corporation (except to the extent CMSI is complying with section 2.1(f)):

(i) The mortgage note, endorsed by manual or facsimile signature without recourse by the Originator or an affiliate of the Originator in blank or to the Trustee showing a complete chain of endorsements and assignments from the named payee to the Trustee or from the named payee to the affiliate of the Originator and from such affiliate to the Trustee.

(ii) The original mortgage, with evidence of recording thereon (if recordation was required under applicable law).

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(iii) Any original assumption, modification, buydown or conversion-to-fixed-interest-rate agreement applicable to the mortgage.

(iv) The original stocks, shares, membership certificate or other contractual agreement evidencing ownership;

(v) The original stock power executed in blank.

(vi) The original executed security agreement or similar document and all assignments thereof showing a complete chain of assignment from the named secured party to the Trustee.

(vii) The original executed proprietary lease or occupancy agreement and all assignments thereof showing a complete chain of assignment from the named secured party to the Trustee.

(viii) The original executed recognition agreement and any executed assignments of recognition agreement showing a complete chain of assignment from the named secured party to the Trustee.

(ix) (Except for mortgage loans (x) secured by mortgaged properties in the State of New Jersey or (y) originated prior to October 1988 and secured by mortgaged properties in the State of New York) the executed UCC-1 financing statement with evidence of recording thereon and executed original UCC-3 financing statements or other appropriate UCC financing statements required by state law, evidencing a complete and unbroken chain from the mortgagee to the Trustee with evidence of recording thereon (or in a form suitable for recordation).

(x) Any related primary mortgage insurance certificate and related policy.

(e) CMSI will, on or before the closing date, deposit in the certificate account

·   all payments on the mortgage loans that CMSI receives after the cut-off date and before the closing date, to the extent such payments are being transferred and assigned to the Trustee under this agreement, except any portion of such payments on mortgage loans (including servicing fees) of a type not required to be deposited therein as specified in section 11 or the Series Terms, and

·   any amount required to be so deposited under the Series Terms.

(f) If CMSI is required under this section 2.1 to deliver an original recorded mortgage or a completed assignment in recordable form to the Mortgage Document Custodian by the closing date, but cannot do so because of a delay in recording the mortgage, CMSI may instead

·   deliver a copy of the mortgage, provided that CMSI certifies that the original mortgage has been delivered to a title insurance company for recordation after receipt of its policy of title insurance or binder therefor (which may be a certificate relating to a master policy of title insurance), and

·   an assignment to the Trustee completed except for recording information.

In all such instances, CMSI will deliver the original recorded mortgage and completed assignment (if applicable) to the Mortgage Document Custodian promptly upon receipt of such mortgage.

If an original recorded mortgage has been lost or misplaced, CMSI or the related title insurance company may deliver, in lieu of the mortgage, a copy of the mortgage bearing recordation information and certified as true and correct by the office in which the original mortgage was recorded.

If CMSI cannot deliver the original or a copy of a title insurance policy (which may be a certificate relating to a master policy of title insurance) for a mortgaged property to the Mortgage Document Custodian by the closing date because the policy is not yet available, CMSI may instead deliver a

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binder for the policy, and deliver the original or a copy of the policy to the Trustee when available.

If CMSI cannot deliver an original assumption, modification, buydown or conversion-to-fixed-interest-rate agreement to the Mortgage Document Custodian by the closing date, CMSI may instead deliver a certified copy thereof. CMSI will deliver the original assumption, modification, buydown or conversion-to-fixed-interest-rate agreement to the Trustee promptly upon receipt thereof.

CMSI will, at its own expense, prepare and deliver to the Mortgage Document Custodian each assignment referred to in clause (a)(iv) or (b)(vi) and (b)(ix) above as soon as practicable but not later than 60 days after the date of initial issuance of the certificates. For each mortgage relating to a mortgaged property located in a state for which the rating agencies require recordation of such assignments (as will be specified in the Series Terms or a CMSI officer’s certificate), CMSI intends to record the assignment in the appropriate public office for real property records (or supply the Mortgage Document Custodian with evidence of recordation) as soon as practicable after the initial issuance of the certificates. Except as provided in this section, neither CMSI nor any Originator or affiliate of any Originator will have any obligation to record any assignment of any mortgage in order to name the Trustee as mortgagee of record. The preceding sentence will not be in derogation of the obligation of CMSI, the Originators and affiliates of the Originators to record (and supply the Mortgage Document Custodian with evidence thereof) assignments of mortgages required in order that CMSI, an Originator or an affiliate of an Originator be shown as mortgagee of record of each mortgage.

CMSI will, at its own expense, record any UCC-3 financing statements not previously recorded, and will supply the Mortgage Document Custodian with evidence of the recordation. CMSI intends to effect recordation in the appropriate public office as soon as practicable after the initial issuance of the certificates.

For mortgage loans that have been prepaid in full after the cut-off date and prior to the closing date, CMSI, in lieu of delivering the above documents to the Mortgage Document Custodian, will on the closing date deliver a certification of a Servicing Officer as set forth in section 3.13.

(g) Concurrently with the transfer and assignment to the Trustee of the mortgage loans, the Trustee or the Authenticating Agent will, in accordance with a written order or request signed in CMSI’s name by an Authorized Officer, authenticate and deliver to or upon CMSI’s order, duly authenticated certificates in authorized denominations evidencing the entire ownership of the Trust Fund. The Trustee acknowledges that to the extent it holds any class P or class L regular interests, it holds such regular interests as assets of the lower-tier or upper-tier REMIC, as described in the Series Terms.

(h) CMSI and the Trustee agree and understand that it is not intended that any mortgage loan be included in the Trust that is a "High-Cost Home Loan," as defined in either the Indiana High Cost Home Loan Law, effective January 1, 2005, the New Jersey Home Ownership Security Act of 2002, effective November 27, 2003, or the New Mexico Home Loan Protection Act, effective January 1, 2004, or a "high cost home mortgage loan," as defined in the Massachusetts Predatory Home Loan Practices Act, effective November 9, 2004.

(i) For purposes of this section 2.1, a document (other than a promissory note,

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letter of credit, investment security or similar instrument that in the ordinary course of business is transferred by delivery with any necessary indorsement or assignment), including any original document, will be deemed "delivered" to a person if the person has received, or been granted unrestricted access to, an image of the document that is inscribed in a tangible medium or is stored in an electronic or other medium and is retrievable in perceivable form.

2.2   CMSI’s representations and warranties 

CMSI represents and warrants to the Trustee and any Insurer that as of the closing date:

(i)   The information in exhibit B was true and correct in all material respects as of the dates respecting which such information is furnished, and the information provided to the rating agencies, including the loan-level detail, is true and correct according to rating agency requirements.

(ii)   As of the closing date, each mortgage will be a valid first lien on the property securing the related mortgage note subject only to

·   the lien of current real property taxes and assessments as limited in clause (vi) below,

·   covenants, conditions and restrictions, rights of way, easements and other matters of public record as of the date of recording of the mortgage, which exceptions appearing of record are acceptable to mortgage lending institutions generally or specifically reflected in the appraisal obtained in connection with the origination of the related mortgage loan,

·   other matters to which like properties are commonly subject that do not in the aggregate materially interfere with the benefits of the security intended to be provided by the mortgage, and

·   for a mortgage on a cooperative apartment in a cooperative housing corporation, the right of the related cooperative to cancel the related shares and terminate the proprietary lease for unpaid assessments (general and special) owed by the mortgagor;

(iii)   Immediately before the transfer and assignment of the mortgage loans to the Trustee, CMSI has good title to, and is the sole legal owner of, each mortgage loan (except as set forth in clause (v) below) and immediately upon the transfer and assignment, CMSI will have taken all steps necessary so that the Trustee will have good title to, and will be the sole legal owner of, each mortgage loan (except as set forth in clause (v) below);

(iv)   As of the cut-off date, no payment of principal of or interest on any mortgage loan was 30 days or more past due (a mortgage loan being considered 30 days past due in a given month when payment due on the first day of the prior month has not been made on or before the last day of such prior month) or has been 30 days or more past due more than once for the twelve months preceding the cut-off date;

(v)   As of the closing date, there is no mechanics’ lien or claim for work, labor or material affecting the mortgaged property that is or may be a lien prior to, or equal with, the lien of the mortgage except those that are insured against by the title insurance policy referred to in (x) below;

(vi)   As of the closing date, there is no delinquent tax or assessment lien against any mortgaged property;

(vii)   As of the closing date, there is no valid offset, defense or counterclaim to any mortgage note or mortgage, including the obligation of the mortgagor to pay the

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unpaid principal and interest on the mortgage note;

(viii)   As of the closing date, each mortgaged property is free of material damage and is in good repair;

(ix)   Each mortgage at the time it was originated complied in all material respects with applicable state, local and federal laws, including, without limitation, all applicable usury, equal credit opportunity, recording, disclosure and predatory lending laws. No mortgage loan is a high cost loan under the predatory lending law of any jurisdiction in which a mortgaged property is located, no mortgage loan is a "High Cost Loan" or "Covered Loan," as such terms are defined in the current version of Standard & Poor’s LEVELS® Glossary, (Version 5.7 Revised, Appendix E), and no mortgage loan originated on or after October 1, 2002 through March 6, 2003 is governed by the Georgia Fair Lending Act;

(x) A lender’s title insurance policy or binder approved as such by Fannie Mae or Freddie Mac, or other assurance of title customary in the relevant jurisdiction, was issued on the date of the origination of each mortgage loan (other than a mortgage loan for a cooperative apartment), and, as of the closing date, each such policy, binder or assurance is valid and in full force and effect;

(xi) The mortgage loans conform in all material respects with their descriptions in the prospectus relating to the certificates;

(xii) Each mortgage loan with an original principal balance exceeding 80% (or, for certain mortgage loans originated before 1995, 90%) of its original value is covered by primary mortgage insurance at least until its outstanding principal balance is less than or equal to 80% of the original value, either through principal payments by the mortgagor or as determined by a new appraisal delivered subsequent to origination. So long as it is in effect, the primary mortgage insurance covers losses from defaults in an amount equal to the excess, of the outstanding principal balance of the mortgage loan over 75% of the original value of the mortgage loan;

(xiii)   The original principal balance of each mortgage loan was not more than 95% of the original value of the mortgage loan;

(xiv) For each buydown mortgage loan, the buydown funds deposited in the buydown account, if any, will be sufficient, after crediting interest at the rate per annum, if any, specified in the buydown agreement compounded monthly to the buydown account and adding the amounts required to be paid by the mortgagor, to make the scheduled payments stated in the mortgage note for the term of the buydown subsidy agreement;

(xv) Each mortgage loan is a "qualified mortgage" within the meaning of Section 860G(a)(3) of the Internal Revenue Code.

(xvi) For each mortgaged property at the time the mortgage loan was originated, no improvement located on or part of the mortgaged property violated any applicable zoning or subdivision laws or ordinances.

(xvii) For each mortgaged property, the terms of the mortgage note and the mortgage loan have not been impaired, altered or modified in any material respect, except by a written instrument which has been recorded or is in the process of being recorded.

(xviii) For each mortgaged property, no default or waiver exists under the mortgage documents, and no modifications to the mortgage documents have been made, that have not been disclosed.

(xix) If a mortgaged property is in a Federal Emergency Management Agency designated flood area, a flood insurance policy is in effect covering the mortgaged property.

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(xx) For each mortgaged property as of the closing date, a hazard insurance policy is in place.

The representations and warranties in this section 2.2 will survive delivery of the mortgage files to the Trustee.

2.3   Repurchase or substitution of mortgage loans 

(a) Each of CMSI, CitiMortgage and the Trustee will promptly notify the other parties if it discovers a breach of any of the representations and warranties in section 2.2 that materially and adversely affects the interests of the certificate holders or any Insurer in a mortgage loan (including a mortgage loan substituted for a nonconforming mortgage loan pursuant to section 2.4) (a material breach ).

(b) Pursuant to the Mortgage Document Custodial Agreement, the Mortgage Document Custodian will review each mortgage note within 90 days after the closing date to ascertain that it has been executed and received, and that such note relates to the mortgage loans identified in exhibit B. If the Mortgage Document Custodian finds that a document in a mortgage file is missing or materially defective, the Mortgage Document Custodian will promptly notify CitiMortgage and CMSI by e-mail.

(c) If CMSI is notified of a material breach, CMSI will have 60 days after the notice (or a longer period approved in advance in writing by a Responsible Officer of the Trustee) to cure the breach in all material respects, or to repurchase the mortgage loan or substitute eligible substitute mortgage loans, as provided in this section 2.3.

If CMSI is notified by the Mortgage Document Custodian that the documentation for a mortgage loan is defective, CMSI will have 180 days after the notice to cure the breach in all material respects, or to repurchase the mortgage loan or substitute eligible substitute mortgage loans, as provided in this section 2.3, except that CMSI will only have 90 days after the notice to cure, cure, repurchase, or substitute if the defect causes the mortgage loan to fail to be a "qualified mortgage" under Internal Revenue Code section 860G(a)(3).

(d) Any repurchase by CMSI of a mortgage loan will be at a price equal to

(i) 100% of the scheduled principal balance of the mortgage loan on the date of repurchase, plus

(ii) accrued and unpaid interest thereon at the pass-through rate to the first day of the following month, plus

(iii) any costs and damages incurred by the Trust Fund in connection with any violation by such mortgage loan of any predatory lending law, plus

(iv) aggregate outstanding advances for the mortgage loan, to the extent not recovered in (ii) above.

(e) CMSI will pay the repurchase price to CitiMortgage, which will promptly deposit the repurchase price in the certificate account. A repurchase of a mortgage loan under this section 2.3 will be considered a prepayment in full of the mortgage loan on the date of repurchase. Upon the Trustee’s receipt of written notice of the deposit signed by an Authorized Officer of CitiMortgage, the Trustee will direct the Mortgage Document Custodian to release the related mortgage file to CMSI and will execute and deliver such instruments of transfer or assignment furnished to the Trustee, in each case without recourse, as CMSI reasonably requests, to vest the mortgage loan in CMSI. Repurchase of the mortgage loan by CMSI will be deemed to include the right to receive any remittance on the mortgage loan payable or received

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on or after the date of repurchase, and CitiMortgage will, upon receipt, promptly pay CMSI the amount of any such remittance.

(f) CMSI may, instead of repurchasing a mortgage loan pursuant to this section 2.3, substitute one or more eligible substitute mortgage loans (as defined below) for one or more nonconforming mortgage loans. Such a substitution will take place on a business day designated by CMSI (the substitution day ) occurring before the second anniversary of the startup day, subject to satisfaction of the conditions in section 2.1 and the following conditions:

(i)   no Event of Default is continuing; and

(ii)   the aggregate scheduled principal balance of all eligible substitute mortgage loans substituted on the substitution day (determined for each eligible substitute mortgage loan as of the substitution day) does not exceed 40% of the aggregate scheduled principal balance of all mortgage loans as of the closing date;

(g) An eligible substitute mortgage loan : is a mortgage loan

·   for which all payments of principal and interest due on or before the substitution day have been received,

·   that has a mortgage note rate equal to or greater than the highest mortgage note rate of any mortgage loan for which it is being substituted,

·   that matures no later than, and no more than one year before, any mortgage loan for which it is being substituted,

·   that has an original term to maturity equal to each mortgage loan for which it is being substituted, and

·   that has a scheduled principal balance that, together with any other eligible substitute mortgage loans being substituted on that substitution day, and any funds CMSI deposits in the certificate account relating to the substitution (the substitution adjustment amount ) equals or exceeds the mortgage loans for which they are being substituted.

The substitution adjustment amount will be separately accounted for as a reserve fund in the certificate account and will be remitted to certificate holders in the month following receipt when the repurchase proceeds are remitted to compensate for the resulting shortfall incurred in connection with the substitution of mortgage loans.

(h) If, on the substitution day, any installment of principal and interest has been received in the certificate account where the principal portion has not been applied to reduce the scheduled principal balance of the mortgage loan that is being substituted for, because the installment was received before the first day of the applicable month, the full amount of such prepaid installment will be paid on the substitution day to CMSI from the certificate account.

(i) Upon a substitution of mortgage loans pursuant to this section 2.3,

·   exhibit B to this agreement will be deemed to be amended to exclude all mortgage loans being replaced by such eligible substitute mortgage loans and to include, pursuant to section 10.1, the information in the supplemental mortgage loan schedule regarding the eligible substitute mortgage loans, and all references in this agreement to mortgage loans will include such eligible substitute mortgage loans,

·   CMSI will be deemed to represent and warrant, as of the substitution day, that the representations and warranties in section 2.2 are true of the eligible substitute mortgage loans, and

·   the Trustee will release to CMSI the nonconforming mortgage loans and execute and deliver any instruments of transfer or

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assignment required to transfer, without recourse, the nonconforming mortgage loans to CMSI.

(j) CMSI’s obligation under this section 2.3 to repurchase or substitute mortgage loans will be the sole remedy against CMSI available to the certificate holders or the Trustee on behalf of the certificate holders for a material defect in a mortgage document or a breach of a representation and warranty in section 2.2.

3   Servicing 

3.1   CitiMortgage as servicer and master servicer

(a) Affiliated mortgage loans . CitiMortgage will service those mortgage loans listed in exhibit B, other than any mortgage loans listed on schedule B-TP (the affiliated mortgage loans ).

(b) Third-party mortgage loans . The mortgage loans listed in schedule B-TP to exhibit B ( third-party mortgage loans ) will be serviced by a third-party servicer pursuant to this agreement, a third-party servicing agreement between CitiMortgage and the third-party servicer, and the Guide. CitiMortgage will be the master servicer for each third-party mortgage loan. Each third-party servicing agreement will be consistent with this agreement and, except for special servicing agreements, will be effective as of the closing date.

(c) Special servicing . CitiMortgage may enter into a special servicing agreement with an unaffiliated person (the class B holder ).