POOLING AND SERVICING AGREEMENT

This Pooling and Servicing Agreement, is dated and effective as of November 1, 2006 among MORTGAGE ASSET SECURITIZATION TRANSACTIONS, INC. as Depositor, BARCLAYS CAPITAL REAL ESTATE INC. d/b/a HOMEQ SERVICING, as a Servicer, WELLS FARGO BANK, N.A., as a Servicer, WELLS FARGO BANK, N.A. as Master Servicer, Trust Administrator and Custodian and U.S. BANK NATIONAL ASSOCIATION as Trustee.

The Depositor intends to sell pass-through certificates to be issued hereunder in multiple classes, which in the aggregate will evidence the entire beneficial ownership interest in each REMIC (as defined herein) created hereunder. The Trust Fund will consist of a segregated pool of assets comprised of the Mortgage Loans and certain other related assets subject to this Agreement.

As provided herein, the Trustee will elect to treat the segregated pool of assets consisting of the Mortgage Loans and certain other related assets (other than the Net WAC Rate Carryover Reserve Account, the Swap Account, the Supplemental Interest Trust, the Interest Rate Swap Agreement, the Cap Account, the Interest Rate Cap Agreement, any Originator Prepayment Charge Payment Amounts and any Servicer Prepayment Charge Payment Amounts) subject to this Agreement as a REMIC for federal income tax purposes, and such segregated pool of assets will be designated as “REMIC I.” The Class R-I Interest will be the sole class of “residual interests” in REMIC I for purposes of the REMIC Provisions (as defined herein). The following table irrevocably sets forth the designation, the REMIC I Remittance Rate, the initial Uncertificated Balance and, for purposes of satisfying Treasury Regulation Section 1.860G-1(a)(4)(iii), the “latest possible maturity date” for each of the REMIC I Regular Interests (as defined herein). None of the REMIC I Regular Interests will be certificated.

As provided herein, the Trustee will elect to treat the segregated pool of assets consisting of the REMIC I Regular Interests as a REMIC for federal income tax purposes, and such segregated pool of assets will be designated as “REMIC II.” The Class R-II Interest will evidence the sole class of “residual interests” in REMIC II for purposes of the REMIC Provisions under federal income tax law. The following table irrevocably sets forth the designation, the REMIC II Remittance Rate, the initial Uncertificated Balance and, for purposes of satisfying Treasury Regulation Section 1.860G-1(a)(4)(iii), the “latest possible maturity date” for each of the REMIC II Regular Interests (as defined herein). None of the REMIC II Regular Interests will be certificated.

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⁽¹⁾   For purposes of Section 1.860G-1(a)(4)(iii) of the Treasury Regulations, the Distribution Date immediately following the maturity date for the Mortgage Loan with the latest maturity date has been designated as the “latest possible maturity date” for each REMIC II Regular Interest.

⁽²⁾   Calculated in accordance with the definition of “REMIC II Remittance Rate” herein.

⁽³⁾   REMIC II Regular Interest II-LTIO will not have an Uncertificated Balance, but will accrue interest on its Uncertificated Notional Amount.

As provided herein, the Trustee will elect to treat the segregated pool of assets consisting of the REMIC II Regular Interests as a REMIC for federal income tax purposes, and such segregated pool of assets will be designated as “REMIC III.” The Class R-III Interest will evidence the sole class of “residual interests” in REMIC III for purposes of the REMIC Provisions under federal income tax law. The following table irrevocably sets forth the designation, the Pass-Through Rate, the initial aggregate Certificate Principal Balance and, for purposes of satisfying Treasury regulation section 1.860G-1(a)(4)(iii), the “latest possible maturity date” for the indicated Classes of Certificates.

Each Certificate, other than the Class P Certificate, the Class CE Certificate, the Class R Certificates and the Class R-X Certificates, represents ownership of a Regular Interest in REMIC III and also represents (i) the right to receive payments with respect to the Net WAC Rate Carryover Amount (as defined herein) and (ii) the obligation to pay Class IO Distribution Amounts (as defined herein). The entitlement to principal of the Regular Interest which corresponds to each Certificate shall be equal in amount and timing to the entitlement to principal of such Certificate. 

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⁽¹⁾   For purposes of Section 1.860G-1(a)(4)(iii) of the Treasury Regulations, the Distribution Date immediately following the maturity date for the Mortgage Loan with the latest maturity date has been designated as the “latest possible maturity date” for each REMIC III Regular Interest.

⁽²⁾   Calculated in accordance with the definition of “Pass-Through Rate” herein.

⁽³⁾   The Class CE Interest will accrue interest at its variable Pass-Through Rate on the Notional Amount of the Class CE Interest outstanding from time to time, which shall equal the Uncertificated Balance of the REMIC II Regular Interests (other than REMIC II Regular Interest II-LTP). The Class CE Interest will not accrue interest on its Uncertificated Balance.

⁽⁴⁾   The Class P Interest will not accrue interest.

⁽⁵⁾   The Class Swap-IO Interest will not have a Pass-Through Rate or a Certificate Principal Balance, but will be entitled to 100% of the amounts distributed on REMIC II Regular Interest II-LTIO.

As provided herein, the Trustee shall make an election to treat the segregated pool of assets consisting of the Class CE Interest as a REMIC for federal income tax purposes, and such segregated pool of assets will be designated as “REMIC IV.” The Class R-IV Interest represents the sole class of “residual interests” in REMIC IV for purposes of the REMIC Provisions.

The following table irrevocably sets forth the Class designation, Pass-Through Rate and Original Class Certificate Principal Balance for the indicated Class of Certificates that represents a “regular interest” in REMIC IV created hereunder:

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⁽¹⁾   For purposes of Section 1.860G-1(a)(4)(iii) of the Treasury Regulations, the Distribution Date immediately following the maturity date for the Mortgage Loans with the latest maturity date has been designated as the “latest possible maturity date” for the Class CE Certificates.

⁽²⁾   The Class CE Certificates will receive 100% of amounts received in respect of the Class CE Interest.

As provided herein, the Trustee shall make an election to treat the segregated pool of assets consisting of the Class P Interest as a REMIC for federal income tax purposes, and such segregated pool of assets will be designated as “REMIC V.” The Class R-V Interest represents the sole class of “residual interests” in REMIC V for purposes of the REMIC Provisions.

The following table irrevocably sets forth the Class designation, Pass-Through Rate and Original Class Certificate Principal Balance for the indicated Class of Certificates that represents a “regular interest” in REMIC V created hereunder:

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⁽¹⁾   For purposes of Section 1.860G-1(a)(4)(iii) of the Treasury Regulations, the Distribution Date immediately following the maturity date for the Mortgage Loans with the latest maturity date has been designated as the “latest possible maturity date” for the Class P Certificates.

⁽²⁾   The Class P Certificates will receive 100% of amounts received in respect of the Class P Interest.

As provided herein, the Trustee shall make an election to treat the segregated pool of assets consisting of the Class SWAP-IO Interest as a REMIC for federal income tax purposes, and such segregated pool of assets shall be designated as “REMIC VI.” The Class R-VI Interest represents the sole class of “residual interests” in REMIC VI for purposes of the REMIC Provisions. The following table irrevocably sets forth the designation, the Pass-Through Rate, the initial aggregate Certificate Principal Balance and, for purposes of satisfying Treasury regulation Section 1.860G-1(a)(4)(iii), the “latest possible maturity date” for the indicated REMIC VI Regular Interest SWAP-IO, which will be uncertificated. 

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As of the Cut-off Date, the Mortgage Loans had an aggregate Stated Principal Balance equal to $600,639,792.36.

In consideration of the mutual agreements herein contained, the Depositor, the Servicer, the Master Servicer, the Trust Administrator and the Trustee agree as follows:

ARTICLE I    

Whenever used in this Agreement, including, without limitation, in the Preliminary Statement hereto, the following words and phrases, unless the context otherwise requires, shall have the meanings specified in this Article. Unless otherwise specified, all calculations described herein shall be made on the basis of a 360-day year consisting of twelve 30-day months.

“10-K Filing Deadline”: The meaning set forth in Section 4.06(a)(iv).

“Accepted Master Servicing Practices”: With respect to any Mortgage Loan, as applicable, either (x) those customary mortgage loan master servicing practices of prudent mortgage servicing institutions that master service mortgage loans of the same type and quality as such Mortgage Loan in the jurisdiction where the related Mortgaged Property is located, to the extent applicable to the Master Servicer (except in its capacity as successor to either Servicer), or (y) as provided in Section 3A.01 hereof, but in no event below the standard set forth in clause (x).

“Accrual Period”: With respect to the Class A Certificates and the Mezzanine Certificates and each Distribution Date, the period commencing on the preceding Distribution Date (or in the case of the first such Accrual Period, commencing on the Closing Date) and ending on the day preceding the current Distribution Date. With respect to the Class CE Certificates and the REMIC Regular Interests and each Distribution Date, the calendar month prior to the month of such Distribution Date.

“Additional Disclosure”: The meaning set forth in Section 4.06(a)(v).

“Additional Form 10-D Disclosure”: The meaning set forth in Section 4.06(a)(i).

“Additional Form 10-K Disclosure”: The meaning set forth in Section 4.06(a)(iv).

“Adjustable-Rate Mortgage Loan”: Each of the Mortgage Loans identified on the Mortgage Loan Schedule as having a Mortgage Rate that is subject to adjustment.

“Adjusted Net Maximum Mortgage Rate”: With respect to any Mortgage Loan (or the related REO Property), as of any date of determination, a per annum rate of interest equal to the applicable Maximum Mortgage Rate for such Mortgage Loan (or the Mortgage Rate in the case of any Fixed-Rate Mortgage Loan) as of the first day of the month preceding the month in which the related Distribution Date occurs minus the sum of (i) the Master Servicer Fee Rate, (ii) the Servicing Fee Rate and (iii) the Credit Risk Manager Fee Rate.  

“Adjusted Net Mortgage Rate”: With respect to any Mortgage Loan (or the related REO Property), as of any date of determination, a per annum rate of interest equal to the applicable Mortgage Rate for such Mortgage Loan as of the first day of the month preceding the month in which the related Distribution Date occurs minus the sum of (i) the Master Servicer Fee Rate, (ii) the Servicing Fee Rate and (iii) the Credit Risk Manager Fee Rate.  

“Adjustment Date”: With respect to each Adjustable-Rate Mortgage Loan, the first day of the month in which the Mortgage Rate of such Mortgage Loan changes pursuant to the related Mortgage Note. The first Adjustment Date following the Cut-off Date as to each Adjustable-Rate Mortgage Loan is set forth in the Mortgage Loan Schedule.

“Advance”: With respect to any Distribution Date, as to any Mortgage Loan or REO Property, any advance made by a Servicer in respect of Monthly Payments due during the related Due Period pursuant to Section 4.03 or by the Master Servicer (in its capacity as successor Servicer) or any other successor Servicer pursuant to Section 4.03.

“Advance Facility”: As defined in Section 3.26 hereof.

“Advancing Person”: As defined in Section 3.26 hereof.

“Affiliate”: With respect to any specified Person, any other Person controlling or controlled by or under common control with such specified Person. For the purposes of this definition, “control” when used with respect to any specified Person means the power to direct the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise, and the terms “controlling” and “controlled” have meanings correlative to the foregoing.

“Aggregate Loss Severity Percentage”: With respect to any Distribution Date, the percentage equivalent of a fraction, the numerator of which is the aggregate amount of Realized Losses incurred on any Mortgage Loans from the Cut-off Date to the last day of the preceding calendar month and the denominator of which is the aggregate Stated Principal Balance of such Mortgage Loans immediately prior to the liquidation of such Mortgage Loans.

“Agreement”: This Pooling and Servicing Agreement and all amendments hereof and supplements hereto.

“Allocated Realized Loss Amount”: With respect to any Distribution Date and any Class of Mezzanine Certificates, (i) the sum of (a) any Realized Losses allocated to such Class of Certificates on such Distribution Date and (b) the amount of any Allocated Realized Loss Amount for such Class of Certificates remaining undistributed from the previous Distribution Date reduced by (ii) the amount of any Subsequent Recoveries added to the Certificate Principal Balance of such Class of Certificates.

“Assessment of Compliance”: As defined in Section 3.21.

“Assignment”: An assignment of Mortgage, notice of transfer or equivalent instrument, in recordable form (excepting therefrom, if applicable, the mortgage recordation information which has not been required pursuant to Section 2.01 hereof or returned by the applicable recorder’s office), which is sufficient under the laws of the jurisdiction wherein the related Mortgaged Property is located to reflect of record the sale of the Mortgage, which assignment, notice of transfer or equivalent instrument may be in the form of one or more blanket assignments covering Mortgages secured by Mortgaged Properties located in the same county, if permitted by law.

“Assignment Agreement”: Each Assignment and Recognition Agreement, dated November 30, 2006, among the Depositor, the Seller and the related Originator, forms of which are attached hereto as Exhibit D, pursuant to which the Seller assigns its rights under the related Originator Master Agreement to the Depositor.

“Attestation Report”: As defined in Section 3.21.

“Available Funds”: With respect to any Distribution Date, an amount equal to the excess of (i) the sum of (a) the aggregate of the related Monthly Payments received on the Mortgage Loans by each Servicer on or prior to the related Determination Date, (b) Net Liquidation Proceeds, Insurance Proceeds, Principal Prepayments, Subsequent Recoveries, proceeds from repurchases of and substitutions for such Mortgage Loans and other unscheduled recoveries of principal and interest in respect of the Mortgage Loans received by each Servicer during the related Prepayment Period, (c) the aggregate of any amounts received by each Servicer in respect of a related REO Property and withdrawn from any REO Account and remitted to the Master Servicer for such Distribution Date, (d) the aggregate of any amounts on deposit in the Distribution Account representing Compensating Interest paid by each Servicer or the Master Servicer in respect of related Prepayment Interest Shortfalls for such Distribution Date, (e) the aggregate of any Advances made by each Servicer for such Distribution Date in respect of the Mortgage Loans and (f) the aggregate of any related Advances made by the Master Servicer (in its capacity as successor servicer) or other successor servicer in respect of the Mortgage Loans for such Distribution Date pursuant to Section 4.03 over (ii) the sum of (a) amounts reimbursable or payable to each Servicer pursuant to Section 3.11(a) or to the Master Servicer pursuant to Section 3A.21, (b) Extraordinary Trust Fund Expenses reimbursable to the Trustee, the Servicers, the Master Servicer or the Trust Administrator pursuant to Section 3A.12, (c) amounts in respect of the items set forth in clauses (i)(a) through (i)(f) above deposited in the Collection Account or the Distribution Account, as the case may be, in error, (d) the amount of any Prepayment Charges collected by each Servicer in connection with the full or partial prepayment of any of the Mortgage Loans, any Originator Prepayment Charge Payment Amount and any Servicer Prepayment Charge Payment Amount, (e) any indemnification and reimbursement amounts owed to the Trust Administrator, the Trustee or the Custodian payable from the Distribution Account pursuant to Section 8.05, (f) the Credit Risk Manager Fee, (g) without duplication, any amounts in respect of the items set forth in clauses (i)(a) and (i)(b) permitted hereunder to be retained by the Master Servicer or to be withdrawn by the Master Servicer from the Distribution Account pursuant to Section 3A.12, (h) Servicing Fees retained by each Servicer pursuant to Section 3.11 and (i) any Net Swap Payment or Swap Termination Payment owed to the Swap Provider (other than any Swap Termination Payment owed to the Swap Provider resulting from a Swap Provider Trigger Event). Notwithstanding any of the foregoing, with respect to any items that are part of the Available Funds as defined above and that are required to be remitted by each Servicer to the Master Servicer, the Available Funds shall not be deemed to include any portion of such items that are not actually remitted by each Servicer to the Master Servicer.

“Back-Up Certification”: The meaning set forth in Section 4.06(a)(iv).

“Balloon Mortgage Loan”: A Mortgage Loan that provides for the payment of the unamortized principal balance of such Mortgage Loan in a single payment at the maturity of such Mortgage Loan that is substantially greater than the preceding monthly payment.

“Balloon Payment”: A payment of the unamortized principal balance of a Mortgage Loan in a single payment at the maturity of such Mortgage Loan that is substantially greater than the preceding Monthly Payment.

“Bankruptcy Code”: The Bankruptcy Reform Act of 1978 (Title 11 of the United States Code), as amended.

“Basic Principal Distribution Amount”: With respect to any Distribution Date, the excess of (i) the Principal Remittance Amount for such Distribution Date over (ii) the Overcollateralization Release Amount, if any, for such Distribution Date.

“Book-Entry Certificate”: The Class A Certificates and the Mezzanine Certificates for so long as the Certificates of such Class shall be registered in the name of the Depository or its nominee.

“Book-Entry Custodian”: The custodian appointed pursuant to Section 5.01.

“Business Day”: Any day other than a Saturday, a Sunday or a day on which banking or savings and loan institutions in the State of New Jersey, the State of California, the State of New York, or in any city in which the Corporate Trust Office of the Trustee or the Corporate Trust Office of the Trust Administrator are located, are authorized or obligated by law or executive order to be closed.

“Cap Account”: The account or accounts created and maintained pursuant to Section 4.10. The Cap Account must be an Eligible Account.

“Certification Parties”: The meaning set forth in Section 4.06(a)(iv).

“Certificate”: Any one of the Mortgage Pass-Through Certificates, Series 2006-HE4, Class A-1, Class A-2, Class A-3, Class A-4, Class M-1, Class M-2, Class M-3, Class M-4, Class M-5, Class M-6, Class M-7, Class M-8, Class M-9, Class M-10, Class M-11, Class CE, Class P, Class R or Class R-X, issued under this Agreement.

“Certificate Factor”: With respect to any Class of Regular Certificates as of any Distribution Date, a fraction, expressed as a decimal carried to at least six places, the numerator of which is the aggregate Certificate Principal Balance (or the Notional Amount, in the case of the Class CE Certificates) of such Class of Certificates on such Distribution Date (after giving effect to any distributions of principal and allocations of Realized Losses in reduction of the Certificate Principal Balance (or the Notional Amount, in the case of the Class CE Certificates) of such Class of Certificates to be made on such Distribution Date), and the denominator of which is the initial aggregate Certificate Principal Balance (or the Notional Amount, in the case of the Class CE Certificates) of such Class of Certificates as of the Closing Date.

“Certificate Margin”: With respect to each Class A Certificate and Mezzanine Certificate and, for purposes of the Marker Rate, the specified REMIC II Regular Interest, as follows:

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“Certificateholder” or “Holder”: The Person in whose name a Certificate is registered in the Certificate Register, except that a Disqualified Organization or a Non-United States Person shall not be a Holder of a Residual Certificate for any purposes hereof and, solely for the purposes of giving any consent pursuant to this Agreement, any Certificate registered in the name of the Depositor, a Servicer or the Master Servicer or any Affiliate thereof shall be deemed not to be outstanding and the Voting Rights to which it is entitled shall not be taken into account in determining whether the requisite percentage of Voting Rights necessary to effect any such consent has been obtained, except as otherwise provided in Section 11.01. The Trust Administrator, the Trustee and the NIMS Insurer may conclusively rely upon a certificate of the Depositor, a Servicer or the Master Servicer in determining whether a Certificate is held by an Affiliate thereof. All references herein to “Holders” or “Certificateholders” shall reflect the rights of Certificate Owners as they may indirectly exercise such rights through the Depository and participating members thereof, except as otherwise specified herein; provided, however, that the Trust Administrator, the Trustee and the NIMS Insurer shall be required to recognize as a “Holder” or “Certificateholder” only the Person in whose name a Certificate is registered in the Certificate Register.

“Certificate Owner”: With respect to a Book-Entry Certificate, the Person who is the beneficial owner of such Certificate as reflected on the books of the Depository or on the books of a Depository Participant or on the books of an indirect participating brokerage firm for which a Depository Participant acts as agent.

“Certificate Principal Balance”: With respect to each Class A Certificate, Mezzanine Certificate or Class P Certificate as of any date of determination, the Certificate Principal Balance of such Certificate on the Distribution Date immediately prior to such date of determination plus any Subsequent Recoveries added to the Certificate Principal Balance of such Certificate pursuant to Section 4.01, minus all distributions allocable to principal made thereon and Realized Losses allocated thereto on such immediately prior Distribution Date (or, in the case of any date of determination up to and including the first Distribution Date, the initial Certificate Principal Balance of such Certificate, as stated on the face thereof). With respect to each Class CE Certificate as of any date of determination, an amount equal to the Percentage Interest evidenced by such Certificate times the excess, if any, of (A) the then aggregate Uncertificated Balance of the REMIC II Regular Interests over (B) the then aggregate Certificate Principal Balance of the Class A Certificates, the Mezzanine Certificates and the Class P Certificates then outstanding.

“Certificate Register”: The register maintained pursuant to Section 5.02.

“Certifying Person”: The meaning set forth in Section 4.06(a)(iv).

“Class”: Collectively, all of the Certificates bearing the same class designation.

“Class A Certificates”: Any of the Class A-1 Certificates, Class A-2 Certificates, Class A-3 Certificates or Class A-4 Certificates.

“Class A-1 Certificate”: Any one of the Class A-1 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-1 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class A-2 Certificate”: Any one of the Class A-2 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-2 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class A-3 Certificate”: Any one of the Class A-3 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-3 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class A-4 Certificate”: Any one of the Class A-4 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-4 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class CE Certificate”: Any one of the Class CE Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-16 and evidencing (i) a Regular Interest in REMIC IV, (ii) the obligation to pay Net WAC Rate Carryover Amounts and Swap Termination Payments and (iii) the right to receive the Class IO Distribution Amount.

“Class CE Interest”: An uncertificated interest in the Trust Fund held by the Trustee on behalf of the Holders of the Class CE Certificates, evidencing a Regular Interest in REMIC III for purposes of the REMIC Provisions.

“Class IO Distribution Amount”: As defined in Section 4.08 hereof. For purposes of clarity, the Class IO Distribution Amount for any Distribution Date shall equal the amount payable to the Trust Administrator on such Distribution Date in excess of the amount payable on the Class SWAP-IO Interest on such Distribution Date, all as further provided in Section 4.08 hereof.

“Class M-1 Certificate”: Any one of the Class M-1 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-5 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-2 Certificate”: Any one of the Class M-2 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-6 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-3 Certificate”: Any one of the Class M-3 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-7 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-4 Certificate”: Any one of the Class M-4 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-8 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-4 Principal Distribution Amount”: With respect to any Distribution Date, the excess of (x) the sum of (i) the aggregate Certificate Principal Balance of the Class A Certificates (after taking into account the distribution of the Senior Principal Distribution Amount on such Distribution Date), (ii) the aggregate Certificate Principal Balance of the Sequential Class M Certificates (after taking into account the distribution of the Sequential Class M Principal Distribution Amount on such Distribution Date) and (iii) the Certificate Principal Balance of the Class M-4 Certificates immediately prior to such Distribution Date over (y) the lesser of (A) the product of (i) 80.20% and (ii) the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) and (B) the excess of the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) over $3,003,198.96.

“Class M-5 Certificate”: Any one of the Class M-5 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-9 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-5 Principal Distribution Amount”: With respect to any Distribution Date, the excess of (x) the sum of (i) the aggregate Certificate Principal Balance of the Class A Certificates (after taking into account the distribution of the Senior Principal Distribution Amount on such Distribution Date), (ii) the aggregate Certificate Principal Balance of the Sequential Class M Certificates (after taking into account the distribution of the Sequential Class M Principal Distribution Amount on such Distribution Date), (iii) the Certificate Principal Balance of the Class M-4 Certificates (after taking into account the distribution of the Class M-4 Principal Distribution Amount on such Distribution Date) and (iv) the Certificate Principal Balance of the Class M-5 Certificates immediately prior to such Distribution Date over (y) the lesser of (A) the product of (i) 83.50% and (ii) the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) and (B) the excess of the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) over $3,003,198.96.

“Class M-6 Certificate”: Any one of the Class M-6 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-10 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-6 Principal Distribution Amount”: With respect to any Distribution Date, the excess of (x) the sum of (i) the aggregate Certificate Principal Balance of the Class A Certificates (after taking into account the distribution of the Senior Principal Distribution Amount on such Distribution Date), (ii) the aggregate Certificate Principal Balance of the Sequential Class M Certificates (after taking into account the distribution of the Sequential Class M Principal Distribution Amount on such Distribution Date), (iii) the Certificate Principal Balance of the Class M-4 Certificates (after taking into account the distribution of the Class M-4 Principal Distribution Amount on such Distribution Date), (iv) the Certificate Principal Balance of the Class M-5 Certificates (after taking into account the distribution of the Class M-5 Principal Distribution Amount on such Distribution Date) and (v) the Certificate Principal Balance of the Class M-6 Certificates immediately prior to such Distribution Date over (y) the lesser of (A) the product of (i) 86.60% and (ii) the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) and (B) the excess of the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) over $3,003,198.96.

“Class M-7 Certificate”: Any one of the Class M-7 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-11 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-7 Principal Distribution Amount”: With respect to any Distribution Date, the excess of (x) the sum of (i) the aggregate Certificate Principal Balance of the Class A Certificates (after taking into account the distribution of the Senior Principal Distribution Amount on such Distribution Date), (ii) the aggregate Certificate Principal Balance of the Sequential Class M Certificates (after taking into account the distribution of the Sequential Class M Principal Distribution Amount on such Distribution Date), (iii) the Certificate Principal Balance of the Class M-4 Certificates (after taking into account the distribution of the Class M-4 Principal Distribution Amount on such Distribution Date), (iv) the Certificate Principal Balance of the Class M-5 Certificates (after taking into account the distribution of the Class M-5 Principal Distribution Amount on such Distribution Date), (v) the Certificate Principal Balance of the Class M-6 Certificates (after taking into account the distribution of the Class M-6 Principal Distribution Amount on such Distribution Date) and (vi) the Certificate Principal Balance of the Class M-7 Certificates immediately prior to such Distribution Date over (y) the lesser of (A) the product of (i) 89.50% and (ii) the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) and (B) the excess of the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) over $3,003,198.96.

“Class M-8 Certificate”: Any one of the Class M-8 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-12 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-8 Principal Distribution Amount”: With respect to any Distribution Date, the excess of (x) the sum of (i) the aggregate Certificate Principal Balance of the Class A Certificates (after taking into account the distribution of the Senior Principal Distribution Amount on such Distribution Date), (ii) the aggregate Certificate Principal Balance of the Sequential Class M Certificates (after taking into account the distribution of the Sequential Class M Principal Distribution Amount on such Distribution Date), (iii) the Certificate Principal Balance of the Class M-4 Certificates (after taking into account the distribution of the Class M-4 Principal Distribution Amount on such Distribution Date), (iv) the Certificate Principal Balance of the Class M-5 Certificates (after taking into account the distribution of the Class M-5 Principal Distribution Amount on such Distribution Date), (v) the Certificate Principal Balance of the Class M-6 Certificates (after taking into account the distribution of the Class M-6 Principal Distribution Amount on such Distribution Date), (vi) the Certificate Principal Balance of the Class M-7 Certificates (after taking into account the distribution of the Class M-7 Principal Distribution Amount on such Distribution Date) and (vii) the Certificate Principal Balance of the Class M-8 Certificates immediately prior to such Distribution Date over (y) the lesser of (A) the product of (i) 92.10% and (ii) the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) and (B) the excess of the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) over $3,003,198.96.

“Class M-9 Certificate”: Any one of the Class M-9 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-13 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-9 Principal Distribution Amount”: With respect to any Distribution Date, the excess of (x) the sum of (i) the aggregate Certificate Principal Balance of the Class A Certificates (after taking into account the distribution of the Senior Principal Distribution Amount on such Distribution Date), (ii) the aggregate Certificate Principal Balance of the Sequential Class M Certificates (after taking into account the distribution of the Sequential Class M Principal Distribution Amount on such Distribution Date), (iii) the Certificate Principal Balance of the Class M-4 Certificates (after taking into account the distribution of the Class M-4 Principal Distribution Amount on such Distribution Date), (iv) the Certificate Principal Balance of the Class M-5 Certificates (after taking into account the distribution of the Class M-5 Principal Distribution Amount on such Distribution Date), (v) the Certificate Principal Balance of the Class M-6 Certificates (after taking into account the distribution of the Class M-6 Principal Distribution Amount on such Distribution Date), (vi) the Certificate Principal Balance of the Class M-7 Certificates (after taking into account the distribution of the Class M-7 Principal Distribution Amount on such Distribution Date), (vii) the Certificate Principal Balance of the Class M-8 Certificates (after taking into account the distribution of the Class M-8 Principal Distribution Amount on such Distribution Date) and (viii) the Certificate Principal Balance of the Class M-9 Certificates immediately prior to such Distribution Date over (y) the lesser of (A) the product of (i) 93.60% and (ii) the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) and (B) the excess of the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) over $3,003,198.96.

“Class M-10 Certificate”: Any one of the Class M-10 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-14 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-10 Principal Distribution Amount”: With respect to any Distribution Date, the excess of (x) the sum of (i) the aggregate Certificate Principal Balance of the Class A Certificates (after taking into account the distribution of the Senior Principal Distribution Amount on such Distribution Date), (ii) the aggregate Certificate Principal Balance of the Sequential Class M Certificates (after taking into account the distribution of the Sequential Class M Principal Distribution Amount on such Distribution Date), (iii) the Certificate Principal Balance of the Class M-4 Certificates (after taking into account the distribution of the Class M-4 Principal Distribution Amount on such Distribution Date), (iv) the Certificate Principal Balance of the Class M-5 Certificates (after taking into account the distribution of the Class M-5 Principal Distribution Amount on such Distribution Date), (v) the Certificate Principal Balance of the Class M-6 Certificates (after taking into account the distribution of the Class M-6 Principal Distribution Amount on such Distribution Date), (vi) the Certificate Principal Balance of the Class M-7 Certificates (after taking into account the distribution of the Class M-7 Principal Distribution Amount on such Distribution Date), (vii) the Certificate Principal Balance of the Class M-8 Certificates (after taking into account the distribution of the Class M-8 Principal Distribution Amount on such Distribution Date), (viii) the Certificate Principal Balance of the Class M-9 Certificates (after taking into account the distribution of the Class M-9 Principal Distribution Amount on such Distribution Date) and (ix) the Certificate Principal Balance of the Class M-10 Certificates immediately prior to such Distribution Date over (y) the lesser of (A) the product of (i) 95.10% and (ii) the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) and (B) the excess of the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) over $3,003,198.96.

“Class M-11 Certificate”: Any one of the Class M-11 Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-15 and evidencing (i) a Regular Interest in REMIC III, (ii) the right to receive the Net WAC Rate Carryover Amount and (iii) the obligation to pay the Class IO Distribution Amount.

“Class M-11 Principal Distribution Amount”: With respect to any Distribution Date, the excess of (x) the sum of (i) the aggregate Certificate Principal Balance of the Class A Certificates (after taking into account the distribution of the Senior Principal Distribution Amount on such Distribution Date), (ii) the aggregate Certificate Principal Balance of the Sequential Class M Certificates (after taking into account the distribution of the Sequential Class M Principal Distribution Amount on such Distribution Date), (iii) the Certificate Principal Balance of the Class M-4 Certificates (after taking into account the distribution of the Class M-4 Principal Distribution Amount on such Distribution Date), (iv) the Certificate Principal Balance of the Class M-5 Certificates (after taking into account the distribution of the Class M-5 Principal Distribution Amount on such Distribution Date), (v) the Certificate Principal Balance of the Class M-6 Certificates (after taking into account the distribution of the Class M-6 Principal Distribution Amount on such Distribution Date), (vi) the Certificate Principal Balance of the Class M-7 Certificates (after taking into account the distribution of the Class M-7 Principal Distribution Amount on such Distribution Date), (vii) the Certificate Principal Balance of the Class M-8 Certificates (after taking into account the distribution of the Class M-8 Principal Distribution Amount on such Distribution Date), (viii) the Certificate Principal Balance of the Class M-9 Certificates (after taking into account the distribution of the Class M-9 Principal Distribution Amount on such Distribution Date), (ix) the Certificate Principal Balance of the Class M-10 Certificates (after taking into account the distribution of the Class M-10 Principal Distribution Amount on such Distribution Date) and (x) the Certificate Principal Balance of the Class M-11 Certificates immediately prior to such Distribution Date over (y) the lesser of (A) the product of (i) 97.10% and (ii) the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) and (B) the excess of the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) over $3,003,198.96.

“Class P Certificate”: Any one of the Class P Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-17 and evidencing a Regular Interest in REMIC V for purposes of the REMIC Provisions.

“Class P Interest”: An uncertificated interest in the Trust Fund held by the Trustee on behalf of the Holders of the Class P Certificates, evidencing a Regular Interest in REMIC III for purposes of the REMIC Provisions.

“Class R Certificate”: Any one of the Class R Certificates executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-18 and evidencing the ownership of the Class R-I Interest, the Class R-II Interest and the Class R-III Interest.

“Class R-X Certificate”: The Class R-X Certificate executed, authenticated and delivered by the Trust Administrator, substantially in the form annexed hereto as Exhibit A-19 and evidencing the ownership of the Class R-IV Interest, the Class R-V Interest and the Class R-VI Interest.

“Class R-I Interest”: The uncertificated Residual Interest in REMIC I.

“Class R-II Interest”: The uncertificated Residual Interest in REMIC II.

“Class R-III Interest”: The uncertificated Residual Interest in REMIC III.

“Class R-IV Interest”: The uncertificated Residual Interest in REMIC IV.

“Class R-V Interest”: The uncertificated Residual Interest in REMIC V.

“Class R-VI Interest”: The uncertificated Residual Interest in REMIC VI.

“Class SWAP-IO Interest”: An uncertificated interest in the Trust Fund evidencing a Regular Interest in REMIC III.

“Closing Date”: November 30 2006.

“Code”: The Internal Revenue Code of 1986, as amended.

“Collection Account”: The account or accounts created and maintained, or caused to be created and maintained, by each Servicer pursuant to Section 3.10(a), which, with respect to the Collection Account created and maintained by HomEq, shall be entitled “HomEq Servicing, as a Servicer for U.S. Bank National Association, as Trustee, in trust for the registered holders of MASTR Asset Backed Securities Trust 2006-HE4, Mortgage Pass-Through Certificates” and with respect to the Collection Account created and maintained by Wells Fargo, shall be entitled “Wells Fargo Bank, N.A., as a Servicer for U.S. Bank National Association, as Trustee, in trust for the registered holders of MASTR Asset Backed Securities Trust 2006-HE4, Mortgage Pass-Through Certificates.” Each Collection Account must be an Eligible Account

“Commission”: The U.S. Securities and Exchange Commission.

“Compensating Interest”: With respect to each Servicer and any Principal Prepayment, the amount in respect of Prepayment Interest Shortfalls required to be paid by the related Servicer pursuant to Section 3.24 from its own funds without right of reimbursement and with respect to the Master Servicer, the amount in respect of Prepayment Interest Shortfalls required to be paid by the Master Servicer pursuant to Section 3A.10 from its own funds without right of reimbursement except as provided in Section 3A.10, in each case, up to the aggregate compensation payable to the related Servicer or the Master Servicer, as applicable, for the related collection period under this Agreement.

“Compensating Interest Payment”: As defined in Section 3.24.

“Corporate Trust Office”: The principal corporate trust office of the Trustee or the Trust Administrator, as the case may be, at which at any particular time its corporate trust business in connection with this Agreement shall be administered, which office at the date of the execution of this instrument is located at (i) with respect to the Trustee, U.S. Bank National Association, 60 Livingston Avenue, EP-MN-WS3D, St. Paul, Minnesota 55107, Attention: Structured Finance/MASTR 2006-HE4, or at such other address as the Trustee may designate from time to time by notice to the Certificateholders, the Depositor, the Servicers, the Master Servicer, the Originators, and the Trust Administrator, or (ii) with respect to the Trust Administrator, (A) for Certificate transfer and surrender purposes, Wells Fargo Bank, N.A., Sixth Street and Marquette Avenue, Minneapolis, Minnesota 55479, Attention: Corporate Trust Services—MASTR 2006-HE4 and (B) for all other purposes, Wells Fargo Bank, N.A., 9062 Old Annapolis Road, Columbia, Maryland 21045, Attention: Corporate Trust Services—MASTR 2006-HE4, or in each case at such other address as the Trust Administrator may designate from time to time by notice to the Certificateholders, the Depositor, the Servicers, the Master Servicer, the Originators and the Trustee.

“Corresponding Certificate”: With respect to each REMIC II Regular Interest set forth below, the corresponding Regular Certificate set forth in the table below:

“Credit Enhancement Percentage”: For any Distribution Date, the percentage equivalent of a fraction, the numerator of which is the aggregate Certificate Principal Balance of the Mezzanine Certificates and the Class CE Certificates, and the denominator of which is the aggregate Stated Principal Balance of the Mortgage Loans, calculated prior to taking into account distributions of principal on the Mortgage Loans and distribution of the Principal Distribution Amount to the Certificates then entitled to distributions of principal on such Distribution Date.

“Credit Risk Management Agreement”: The respective agreements between the Credit Risk Manager and each Servicer and/or Master Servicer regarding the loss mitigation and advisory services to be provided by the Credit Risk Manager.

“Credit Risk Manager”: Clayton Fixed Income Services Inc., a Colorado corporation, formerly known as The Murrayhill Company, and its successors and assigns.

“Credit Risk Manager Fee”: The amount payable to the Credit Risk Manager on each Distribution Date as compensation for all services rendered by it in the exercise and performance of any of the powers and duties of the Credit Risk Manager under the respective Credit Risk Management Agreement and any other agreement pursuant to which the Credit Risk Manager is to perform any duties with respect to the related Mortgage Loans, which amount shall equal one twelfth of the product of (i) the Credit Risk Manager Fee Rate (without regard to the words “per annum”) and (ii) the aggregate Stated Principal Balance of the related Mortgage Loans and any related REO Properties as of the first day of the related Due Period.

“Credit Risk Manager Fee Rate”: 0.0125% per annum.

“Cumulative Loss Percentage”: With respect to any Distribution Date, the percentage equivalent of a fraction, the numerator of which is the aggregate amount of Realized Losses incurred from the Cut-off Date to the last day of the preceding calendar month and the denominator of which is the sum of the aggregate Stated Principal Balance of the Mortgage Loans as of the Cut-off Date.

“Custodian”: The entity acting as custodian of the Mortgage Files on behalf of and for the benefit of the Trustee, which as of the Closing Date shall be Wells Fargo.

“Cut-off Date”: With respect to each Original Mortgage Loan, November 1, 2006. With respect to all Qualified Substitute Mortgage Loans, their respective dates of substitution. References herein to the “Cut-off Date,” when used with respect to more than one Mortgage Loan, shall be to the respective Cut-off Dates for such Mortgage Loans.

“Cut-off Date Principal Balance”: With respect to any Mortgage Loan, the unpaid Stated Principal Balance thereof as of the Cut-off Date of such Mortgage Loan (or as of the applicable date of substitution with respect to a Qualified Substitute Mortgage Loan), after giving effect to scheduled payments due on or before the Cut-off Date, whether or not received.

“Debt Service Reduction”: With respect to any Mortgage Loan, a reduction in the scheduled Monthly Payment for such Mortgage Loan by a court of competent jurisdiction in a proceeding under the Bankruptcy Code, except such a reduction resulting from a Deficient Valuation.

“Deficient Valuation”: With respect to any Mortgage Loan, a valuation of the related Mortgaged Property by a court of competent jurisdiction in an amount less than the then outstanding principal balance of the Mortgage Loan, which valuation results from a proceeding initiated under the Bankruptcy Code.

“Definitive Certificates”: As defined in Section 5.01(b).

“Deleted Mortgage Loan”: A Mortgage Loan replaced or to be replaced by a Qualified Substitute Mortgage Loan.

“Delinquency Percentage”: With respect to any Distribution Date, the percentage equivalent to a fraction, the numerator of which is the aggregate Stated Principal Balance of all Mortgage Loans that, as of the close of business on the last day of the previous calendar month, are 60 or more days Delinquent (including Mortgage Loans in foreclosure, have been converted to REO Properties or are in bankruptcy), taking into account any prepayments received through the end of the related Prepayment Period, and the denominator of which is the aggregate Principal Balance of all Mortgage Loans as of the close of business on the last day of such month, taking into account any prepayments received through the end of the related Prepayment Period.

“Delinquent”: A Mortgage Loan is Delinquent if any Monthly Payment due on a Due Date is not made by the close of business on the next scheduled Due Date for such Mortgage Loan (as determined and reported based on the “OTS” methodology for determining delinquencies on mortgage loans similar to the Mortgage Loans and not including any Liquidated Mortgage Loans).

“Depositor”: Mortgage Asset Securitization Transactions, Inc., a Delaware corporation, or its successor in interest.

“Depository”: The Depository Trust Company, or any successor Depository hereafter named. The nominee of the initial Depository, for purposes of registering those Certificates that are to be Book-Entry Certificates, is Cede & Co. The Depository shall at all times be a “clearing corporation” as defined in Section 8-102(3) of the Uniform Commercial Code of the State of New York and a “clearing agency” registered pursuant to the provisions of Section 17A of the Securities Exchange Act of 1934, as amended.

“Depository Participant”: A broker, dealer, bank or other financial institution or other Person for whom from time to time a Depository effects book-entry transfers and pledges of securities deposited with the Depository.

“Determination Date”: With respect to any Distribution Date, the 15 ^th day of the calendar month in which such Distribution Date occurs or, if such 15 ^th day is not a Business Day, the Business Day immediately preceding such 15 ^th day.

“Directly Operate”: With respect to any REO Property, the furnishing or rendering of services to the tenants thereof, the management or operation of such REO Property, the holding of such REO Property primarily for sale to customers, the performance of any construction work thereon or any use of such REO Property in a trade or business conducted by REMIC I other than through an Independent Contractor; provided, however, that the Trustee (or the Servicers or the Master Servicer on behalf of the Trustee) shall not be considered to Directly Operate an REO Property solely because the Trustee (or the Servicers or the Master Servicer on behalf of the Trustee) establishes rental terms, chooses tenants, enters into or renews leases, deals with taxes and insurance, or makes decisions as to repairs or capital expenditures with respect to such REO Property.

“Discount Factor”:   With respect to each Distribution Date, the product of each Projected Zero Factor for each preceding Distribution Date, including such Distribution Date, with the Projected Zero Factor for the Significance Percentage Calculation Date equal to 1.

“Disqualified Organization”: Any of the following: (i) the United States, any State or political subdivision thereof, any possession of the United States, or any agency or instrumentality of any of the foregoing (other than an instrumentality which is a corporation if all of its activities are subject to tax and, except for Freddie Mac, a majority of its board of directors is not selected by such governmental unit), (ii) any foreign government, any international organization, or any agency or instrumentality of any of the foregoing, (iii) any organization (other than certain farmers’ cooperatives described in Section 521 of the Code) which is exempt from the tax imposed by Chapter 1 of the Code (including the tax imposed by Section 511 of the Code on unrelated business taxable income), (iv) rural electric and telephone cooperatives described in Section 1381(a)(2)(C) of the Code, (v) an “electing large partnership” and (vi) any other Person so designated by the Trustee or the Trust Administrator based upon an Opinion of Counsel that the holding of an Ownership Interest in a Residual Certificate by such Person may cause any Trust REMIC or any Person having an Ownership Interest in any Class of Certificates (other than such Person) to incur a liability for any federal tax imposed under the Code that would not otherwise be imposed but for the Transfer of an Ownership Interest in a Residual Certificate to such Person. The terms “United States,” “State” and “international organization” shall have the meanings set forth in Section 7701 of the Code or successor provisions.

“Distribution Account”: The trust account or accounts created and maintained by the Trust Administrator pursuant to Section 3A.11 which shall be entitled “Wells Fargo Bank, N.A. as Trust Administrator, in trust for the registered holders of MASTR Asset Backed Securities Trust 2006-HE4, Mortgage Pass-Through Certificates, Series 2006-HE4—Distribution Account.” The Distribution Account must be an Eligible Account.

“Distribution Date”: The 25 ^th day of any month, or if such 25 ^th day is not a Business Day, the Business Day immediately following such 25 ^th day, commencing in December 2006.

“Due Date”: With respect to each Distribution Date, the first day of the calendar month in which such Distribution Date occurs, which is generally the day of the month on which the Monthly Payment is due on a Mortgage Loan, exclusive of any days of grace.

“Due Period”: With respect to any Distribution Date, the period commencing on the second day of the month immediately preceding the month in which such Distribution Date occurs and ending on the related Due Date.

“Eligible Account”: Any of (i) an account or accounts maintained with a federal or state chartered depository institution or trust company the short-term unsecured debt obligations of which (or, in the case of a depository institution or trust company that is the principal subsidiary of a holding company, the short-term unsecured debt obligations of such holding company) are rated P-1 by Moody’s or A-1+ by S&P (or comparable ratings if Moody’s and S&P are not the Rating Agencies) at the time any amounts are held on deposit therein, (ii) with respect to any escrow account, an account or accounts the deposits in which are fully insured by the FDIC (to the limits established by such corporation), the uninsured deposits in which account are otherwise secured such that, as evidenced by an Opinion of Counsel delivered to the NIMS Insurer, the Trust Administrator, the Trustee and to each Rating Agency, the Certificateholders will have a claim with respect to the funds in such account or a perfected first priority security interest against such collateral (which shall be limited to Permitted Investments) securing such funds that is superior to claims of any other depositors or creditors of the depository institution with which such account is maintained, (iii) a trust account or accounts maintained with the trust department of a federal or state chartered depository institution, national banking association or trust company acting in its fiduciary capacity or (iv) an account otherwise acceptable to the NIMS Insurer and to each Rating Agency without reduction or withdrawal of their then current ratings of the Certificates as evidenced by a letter from each Rating Agency to the Trust Administrator, the Trustee and the NIMS Insurer. Eligible Accounts may bear interest.

“ERISA”: The Employee Retirement Income Security Act of 1974, as amended.

“Estate in Real Property”: A fee simple estate in a parcel of land.

“Excess Overcollateralized Amount”: With respect to the Class A Certificates and the Mezzanine Certificates and any Distribution Date, the excess, if any, of (i) the Overcollateralized Amount for such Distribution Date, assuming that 100% of the Principal Remittance Amount is applied as a principal distribution on such Distribution Date over (ii) the Overcollateralization Target Amount for such Distribution Date.

“Exchange Act”: The Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder.

“Extra Principal Distribution Amount”: With respect to any Distribution Date, the lesser of (x) the sum of (i) Monthly Interest Distributable Amount payable on the Class CE Certificates on such Distribution Date as reduced by Realized Losses allocated thereto with respect to such Distribution Date pursuant to Section 4.04 and (ii) any amounts received under the Interest Rate Swap Agreement or the Interest Rate Cap Agreement for this purpose and (y) the Overcollateralization Deficiency Amount for such Distribution Date.

“Extraordinary Trust Fund Expense”: Any amounts reimbursable to the Master Servicer pursuant to Section 3A.03 or Section 6.03, to the Trustee pursuant to Section 3.06 or Section 7.02, to each Servicer, the Trustee or the Trust Administrator, or any director, officer, employee or agent of the Trustee or the Trust Administrator from the Trust Fund pursuant to Section 6.03, Section 8.05 or Section 10.01(c) and any amounts payable from the Distribution Account in respect of taxes pursuant to Section 10.01(g)(iii).

“Fannie Mae”: Fannie Mae, formerly known as the Federal National Mortgage Association, or any successor thereto.

“FDIC”: Federal Deposit Insurance Corporation or any successor thereto.

“Final Recovery Determination”: With respect to any defaulted Mortgage Loan or any REO Property (other than a Mortgage Loan or REO Property purchased or repurchased by an Originator, the Seller, the Depositor, a Servicer or the NIMS Insurer pursuant to or as contemplated by Section 2.03, Section 3.16(c) or Section 9.01), a determination made by the related Servicer that all Insurance Proceeds, Liquidation Proceeds and other payments or recoveries which the related Servicer, in its reasonable good faith judgment, expects to be finally recoverable in respect thereof have been so recovered. Each Servicer shall maintain records, prepared by a Servicing Officer, of each Final Recovery Determination made thereby.

“Fixed-Rate Mortgage Loans”: Each of the Mortgage Loans identified in the Mortgage Loan Schedule whose Mortgage Rates remain fixed for the life of the Mortgage Loan.

“Fixed Swap Payment”: With respect to any Distribution Date, a fixed amount equal to the related amount set forth in the Interest Rate Swap Agreement.

“Floating Swap Payment”: With respect to any Distribution Date, a floating amount equal to the product of (i) one-month LIBOR (as determined pursuant to the Interest Rate Swap Agreement for such Distribution Date), (ii) the related Base Calculation Amount (as defined in the Interest Rate Swap Agreement), (iii) 250 and (iv) a fraction, the numerator of which is the actual number of days elapsed from and including the previous Distribution Date to but excluding the current Distribution Date (or, for the first Distribution Date, the actual number of days elapsed from the Closing Date to but excluding the first Distribution Date), and the denominator of which is 360.

“Form 8-K Disclosure Information”: The meaning set forth in Section 4.06(a)(iii).

“Formula Rate”: For any Distribution Date and the Class A Certificates and the Mezzanine Certificates, the lesser of (i) One-Month LIBOR plus the related Certificate Margin and (ii) the Maximum Cap Rate.

“Freddie Mac”: Freddie Mac, formerly known as the Federal Home Loan Mortgage Corporation, or any successor thereto.

“Gross Margin”: With respect to each Adjustable-Rate Mortgage Loan, the fixed percentage set forth in the related Mortgage Note that is added to the Index on each Adjustment Date in accordance with the terms of the related Mortgage Note used to determine the Mortgage Rate for such Adjustable-Rate Mortgage Loan.

“Highest Priority”: As of any date of determination, the Class of Mezzanine Certificates then outstanding with a Certificate Principal Balance greater than zero, with the highest priority for payments pursuant to Section 4.01, in the following order: Class M-1, Class M-2, Class M-3, Class M-4, Class M-5, Class M-6, Class M-7, Class M-8, Class M-9, Class M-10 and Class M-11 Certificates.

“HomEq”: Barclays Capital Real Estate Inc. d/b/a HomEq Servicing.

“HomEq Mortgage Loans”: The Mortgage Loans serviced by HomEq.

“Indenture”: An indenture relating to the issuance of notes secured by the Class CE Certificates, the Class P Certificates, the Class R Certificates and/or the Class R-X Certificates (or any portion thereof) which may or may not be guaranteed by the NIMS Insurer.

“Independent”: When used with respect to any accountants, a Person who is “independent” within the meaning of Rule 2-01(B) of the Securities and Exchange Commission’s Regulation S-X. Independent means, when used with respect to any other Person, a Person who (A) is in fact independent of another specified Person and any affiliate of such other Person, (B) does not have any material direct or indirect financial interest in such other Person or any affiliate of such other Person, (C) is not connected with such other Person or any affiliate of such other Person as an officer, employee, promoter, underwriter, trustee, partner, director or Person performing similar functions and (D) is not a member of the immediate family of a Person defined in clause (B) or (C) above .

“Independent Contractor”: Either (i) any Person (other than a Servicer or the Master Servicer) that would be an “independent contractor” with respect to REMIC I within the meaning of Section 856(d)(3) of the Code if REMIC I were a real estate investment trust (except that the ownership tests set forth in that section shall be considered to be met by any Person that owns, directly or indirectly, 35% or more of any Class of Certificates), so long as REMIC I does not receive or derive any income from such Person and provided that the relationship between such Person and REMIC I is at arm’s length, all within the meaning of Treasury Regulation Section 1.856-4(b)(5), or (ii) any other Person (including either Servicer and the Master Servicer) if the Trust Administrator has received an Opinion of Counsel for the benefit of the Trustee and the Trust Administrator to the effect that the taking of any action in respect of any REO Property by such Person, subject to any conditions therein specified, that is otherwise herein contemplated to be taken by an Independent Contractor will not cause such REO Property to cease to qualify as “foreclosure property” within the meaning of Section 860G(a)(8) of the Code (determined without regard to the exception applicable for purposes of Section 860D(a) of the Code), or cause any income realized in respect of such REO Property to fail to qualify as Rents from Real Property.

“Index”: With respect to each Adjustable Rate Mortgage Loan and with respect to each related Adjustment Date, the index specified in the related Mortgage Note.

“Insurance Proceeds”: Proceeds of any title policy, hazard policy or other insurance policy, covering a Mortgage Loan to the extent such proceeds are not to be applied to the restoration of the related Mortgaged Property or released to the Mortgagor in accordance with the procedures that the related Servicer would follow in servicing mortgage loans held for its own account, subject to the terms and conditions of the related Mortgage Note and Mortgage.

“Interest Determination Date”: With respect to the Class A Certificates, the Mezzanine Certificates, REMIC II Regular Interest II-LTA1, REMIC II Regular Interest II-LTA2, REMIC II Regular Interest II-LTA3, REMIC II Regular Interest II-LTA4, REMIC II Regular Interest II-LTM1, REMIC II Regular Interest II-LTM2, REMIC II Regular Interest II-LTM3, REMIC II Regular Interest II-LTM4, REMIC II Regular Interest II-LTM5, REMIC II Regular Interest II-LTM6, REMIC II Regular Interest II-LTM7, REMIC II Regular Interest II-LTM8, REMIC II Regular Interest II-LTM9, REMIC II Regular Interest II-LTM10 and REMIC II Regular Interest II-LTM11 and any Accrual Period therefor, the second London Business Day preceding the commencement of such Accrual Period.

“Interest Rate Cap Collateral Account”: Shall mean the segregated trust account created and maintained by the Trust Administrator pursuant to Section 4.11 hereof.

“Interest Rate Cap Agreement”: The Interest Rate Cap Agreement, dated as of November 30, 2006, between the Trust Administrator and the Interest Rate Cap Provider, including any schedule, confirmations, credit support annex or other credit support document relating thereto, and attached hereto as Exhibit K.

“Interest Rate Cap Credit Support Annex”: The credit support annex, dated as of November 30, 2006, between the Trust Administrator and the Interest Rate Cap Provider, which is annexed to and forms part of the Interest Rate Cap Agreement.

“Interest Rate Cap Provider”: The cap provider under the Interest Rate Cap Agreement. Initially, the Interest Rate Cap Provider shall be Swiss Re Financial Products Corporation.

“Interest Rate Swap Agreement”: The interest rate swap agreement, dated as of November 30, 2006, between the Swap Provider and the Supplemental Interest Trust Trustee, including any schedule, confirmations, credit support annex and/or other credit support documents relating thereto, and attached hereto as Exhibit M.

“Interest Remittance Amount”: With respect to any Distribution Date, that portion of the Available Funds for such Distribution Date attributable to interest received or advanced with respect to the Mortgage Loans.

“Late Collections”: With respect to any Mortgage Loan and any Due Period, all amounts received by the related Servicer subsequent to the Determination Date immediately following such Due Period, whether as late payments of Monthly Payments or as Insurance Proceeds, Liquidation Proceeds or otherwise, which represent late payments or collections of principal and/or interest due (without regard to any acceleration of payments under the related Mortgage and Mortgage Note) but delinquent for such Due Period and not previously recovered.

“Liquidated Mortgage Loan”: As to any Distribution Date, any Mortgage Loan in respect of which the related Servicer has determined, in its reasonable judgment, as of the end of the related Prepayment Period, that all Liquidation Proceeds which it expects to recover with respect to the liquidation of the Mortgage Loan or disposition of the related REO Property have been recovered.

“Liquidation Event”: With respect to any Mortgage Loan, any of the following events: (i) such Mortgage Loan is paid in full; (ii) a Final Recovery Determination is made as to such Mortgage Loan; or (iii) such Mortgage Loan is removed from REMIC I by reason of its being purchased, repurchased or replaced pursuant to or as contemplated by Section 2.03, Section 3.16(c) or Section 9.01. With respect to any REO Property, either of the following events: (i) a Final Recovery Determination is made as to such REO Property; or (ii) such REO Property is removed from REMIC I by reason of its being purchased pursuant to Section 9.01.

“Liquidation Proceeds”: The amount (other than amounts received in respect of the rental of any REO Property prior to REO Disposition) received by the related Servicer in connection with (i) the taking of all or a part of a Mortgaged Property by exercise of the power of eminent domain or condemnation, (ii) the liquidation of a defaulted Mortgage Loan through a trustee’s sale, foreclosure sale or otherwise, or (iii) the purchase, repurchase or substitution of a Mortgage Loan or an REO Property pursuant to or as contemplated by Section 2.03, Section 3.16(c) or Section 9.01.

“Loan-to-Value Ratio”: As of any date of determination, the fraction, expressed as a percentage, the numerator of which is the principal balance of the related Mortgage Loan at such date and the denominator of which is the Value of the related Mortgaged Property.

“London Business Day”: Any day on which banks in the City of London and the City of New York are open and conducting transactions in United States dollars.

“Loss Severity Percentage”: With respect to any Distribution Date, the percentage equivalent of a fraction, the numerator of which is the amount of Realized Losses incurred on a Mortgage Loan and the denominator of which is the principal balance of such Mortgage Loan immediately prior to the liquidation of such Mortgage Loan.

“Marker Rate”: With respect to the Class CE Interest and any Distribution Date, a per annum rate equal to two (2) times the weighted average of the REMIC II Remittance Rate for each of REMIC II Regular Interests II-LTA1, II-LTA2, II-LTA3, II-LTA4, II-LTM1, II-LTM2, II-LTM3, II-LTM4, II-LTM5, II-LTM6, II-LTM7, II-LTM8, II-LTM9, II-LTM10, II-LTM11 and II-LTZZ, with the rate on each such REMIC II Regular Interest (other than REMIC II Regular Interest II-LTZZ) subject to a cap equal to the lesser of (a) One-Month LIBOR plus the related Certificate Margin and (b) the Net WAC Rate for the purpose of this calculation and with the rate on REMIC II Regular Interest II-LTZZ subject to a cap of zero for the purpose of this calculation; provided, however, that solely for this purpose, calculations of the REMIC II Remittance Rate and the related caps with respect to such REMIC II Regular Interests (other than REMIC II Regular Interest II-LTZZ) shall be multiplied by a fraction, the numerator of which is the actual number of days elapsed in the related Accrual Period and the denominator of which is 30.

“Master Servicer”: As of the Closing Date, Wells Fargo and thereafter, its respective successors in interest who meet the qualifications of the Master Servicer under this Agreement or any successor appointed hereunder. The Master Servicer and the Trust Administrator shall at all times be the same Person.

“Master Servicer Event of Default”: One or more of the events described in Section 7.01(b).

“Master Servicing Compensation”: The meaning specified in Section 3A.09.

“Master Servicer Fee”: With respect to each Mortgage Loan, the amount of the annual fee paid to the Master Servicer, which shall, for a period of one full month, be equal to one-twelfth of the product of (a) the Master Servicer Fee Rate (without regard to the words “per annum”) and (b) the Stated Principal Balance of such Mortgage Loan as of the first day of the related Due Period. Such fee shall be payable monthly, computed on the basis of the same principal amount and period respecting which any related interest payment on a Mortgage Loan is received.

“Master Servicer Fee Rate”: With respect to each Mortgage Loan, the rate of 0.0020% per annum.

“Master Servicing Transfer Costs”: Shall mean all reasonable out-of-pocket costs and expenses incurred by the Trustee in connection with the transfer of master servicing from a predecessor master servicer, including, without limitation, any reasonable costs or expenses associated with the complete transfer of all servicing data and master servicing data and the completion, correction or manipulation of such servicing data as may be required by the Trustee to correct any errors or insufficiencies in the servicing data or otherwise to enable the Trustee to master service the Mortgage Loans properly and effectively.

Maximum Cap Rate”: For any Distribution Date with respect to the Class A Certificates and the Mezzanine Certificates, a per annum rate equal to the sum of (i) the product of (x) the weighted average of the Adjusted Net Maximum Mortgage Rates of the Mortgage Loans, weighted based on their outstanding Stated Principal Balances as of the first day of the calendar month preceding the month in which the Distribution Date occurs and (y) a fraction, the numerator of which is 30 and the denominator of which is the actual number of days elapsed in the related Accrual Period and (ii) (A) an amount, expressed as a percentage, equal to a fraction, the numerator of which is equal to the Net Swap Payment made by the Swap Provider and the denominator of which is equal to the aggregate Stated Principal Balance of the Mortgage Loans, multiplied by 12 and (B) an amount, expressed as a percentage, equal to a fraction, the numerator of which is equal to payments received under the Interest Rate Cap Agreement and the denominator of which is equal to the aggregate Stated Principal Balance of the Mortgage Loans, multiplied by 12 minus (a) an amount, expressed as a percentage, equal to the product of (I) the Net Swap Payment, if any, paid by the Trust for such Distribution Date divided by the aggregate Stated Principal Balance of the Mortgage Loans and (II) 12 and (b) an amount, expressed as a percentage, equal to the product of (x) the Swap Termination Payment, if any, due from the Trust (other than any Swap Termination Payment resulting from a Swap Provider Trigger Event) for such Distribution Date, divided by the aggregate Stated Principal Balance of the Mortgage Loans and (y) 12.

“Maximum II-LTZZ Uncertificated Interest Deferral Amount”: With respect to any Distribution Date, the excess of (i) accrued interest at the REMIC II Remittance Rate applicable to REMIC II Regular Interest II-LTZZ for such Distribution Date on a balance equal to the Uncertificated Balance of REMIC II Regular Interest II-LTZZ minus the REMIC II Overcollateralization Amount, in each case for such Distribution Date, over (ii) Uncertificated Interest on REMIC II Regular Interest II-LTA1, REMIC II Regular Interest II-LTA2, REMIC II Regular Interest II-LTA3, REMIC II Regular Interest II-LTA4, REMIC II Regular Interest II-LTM1, REMIC II Regular Interest II-LTM2, REMIC II Regular Interest II-LTM3, REMIC II Regular Interest II-LTM4, REMIC II Regular Interest II-LTM5, REMIC II Regular Interest II-LTM6, REMIC II Regular Interest II-LTM7, REMIC II Regular Interest II-LTM8, REMIC II Regular Interest II-LTM9, REMIC II Regular Interest II-LTM10, REMIC II Regular Interest II-LTM11 for such Distribution Date, with the rate on each such REMIC II Regular Interest subject to a cap equal to the lesser of (a) One-Month LIBOR plus the related Certificate Margin and (b) the Net WAC Rate; provided, however, each cap shall be multiplied by a fraction, the numerator of which is the actual number of days elapsed in the related Accrual Period and the denominator of which is 30.

“Maximum Mortgage Rate”: With respect to each Adjustable-Rate Mortgage Loan, the percentage set forth in the related Mortgage Note as the maximum Mortgage Rate thereunder.

“MERS”: Mortgage Electronic Registration Systems, Inc., a corporation organized and existing under the laws of the State of Delaware, or any successor thereto.

“MERS® System”: The system of recording transfers of Mortgages electronically maintained by MERS.

“Mezzanine Certificate”: Any Class M-1 Certificate, Class M-2 Certificate, Class M-3 Certificate, Class M-4 Certificate, Class M-5 Certificate, Class M-6 Certificate, Class M-7 Certificate, Class M-8 Certificate, Class M-9 Certificate, Class M-10 Certificate or Class M-11 Certificate.

“MIN”: The Mortgage Identification Number for Mortgage Loans registered with MERS on the MERS® System.

“Minimum Mortgage Rate”: With respect to each Adjustable-Rate Mortgage Loan, the percentage set forth in the related Mortgage Note as the minimum Mortgage Rate thereunder.

“MOM Loan”: With respect to any Mortgage Loan, MERS acting as the mortgagee of such Mortgage Loan, solely as nominee for the originator of such Mortgage Loan and its successors and assigns, at the origination thereof.

“Monthly Interest Distributable Amount”: With respect to the Class A Certificates, the Mezzanine Certificates and the Class CE Certificates and any Distribution Date, the amount of interest accrued during the related Accrual Period at the related Pass-Through Rate on the Certificate Principal Balance (or Notional Amount in the case of the Class CE Certificates) of such Class immediately prior to such Distribution Date, calculated on an actual/360 basis, reduced (to not less than zero) by any Prepayment Interest Shortfalls (to the extent not covered by payments made by the related Servicer or the Master Servicer) and Relief Act Interest Shortfalls (allocated to each such Certificate based on its respective entitlements to interest irrespective of any Prepayment Interest Shortfalls and Relief Act Interest Shortfalls for such Distribution Date).

“Monthly Payment”: With respect to any Mortgage Loan, the scheduled monthly payment of principal and interest on such Mortgage Loan which is payable by the related Mortgagor from time to time under the related Mortgage Note, determined: (a) after giving effect to (i) any Deficient Valuation and/or Debt Service Reduction with respect to such Mortgage Loan and (ii) any reduction in the amount of interest collectible from the related Mortgagor pursuant to the Relief Act; (b) without giving effect to any extension granted or agreed to by the related Servicer pursuant to Section 3.07 and (c) on the assumption that all other amounts, if any, due under such Mortgage Loan are paid when due.

“Monthly Statement”: The statement prepared by the Trust Administrator pursuant to Section 4.02.

“Moody’s”: Moody’s Investors Service, Inc. or its successor in interest.

“Mortgage”: The mortgage, deed of trust or other instrument creating a first or second lien on, or first or second priority security interest in, a Mortgaged Property securing a Mortgage Note.

“Mortgage File”: The mortgage documents listed in Section 2.01 pertaining to a particular Mortgage Loan and any additional documents required to be added to the Mortgage File pursuant to this Agreement.

“Mortgage Loan”: Any Adjustable-Rate Mortgage Loan or Fixed-Rate Mortgage Loan transferred and assigned to the Trustee and delivered to the Trustee pursuant to Section 2.01 or Section 2.03(b) of this Agreement as held from time to time as a part of the Trust, the Mortgage Loans so held being identified in the Mortgage Loan Schedule.

“Mortgage Loan Schedule”: As of any date, the list of Mortgage Loans included in REMIC I on such date, attached hereto as Schedule 1. The Mortgage Loan Schedule shall set forth the following information with respect to each Mortgage Loan:

The Mortgage Loan Schedule shall set forth the following information with respect to the Mortgage Loans in the aggregate as of the Cut-off Date: (1) the number of Mortgage Loans (separately identifying the number of Fixed-Rate Mortgage Loans and the number of Adjustable-Rate Mortgage Loans); (2) the current Stated Principal Balance of the Mortgage Loans; (3) the weighted average Mortgage Rate of the Mortgage Loans and (4) the weighted average maturity of the Mortgage Loans. The Mortgage Loan Schedule shall be amended from time to time by the Depositor in accordance with the provisions of this Agreement. With respect to any Qualified Substitute Mortgage Loan, the Cut-off Date shall refer to the related Cut-off Date for such Mortgage Loan, determined in accordance with the definition of Cut-off Date herein.

“Mortgage Note”: The original executed note or other evidence of the indebtedness of a Mortgagor under a Mortgage Loan.

“Mortgage Pool”: The pool of Mortgage Loans, identified on the Mortgage Loan Schedule and existing from time to time thereafter, and any REO Properties acquired in respect thereof.

“Mortgage Rate”: With respect to each Mortgage Loan, the annual rate at which interest accrues on such Mortgage Loan from time to time in accordance with the provisions of the related Mortgage Note, which rate with respect to the Adjustable-Rate Mortgage Loans, (A) as of any date of determination until the first Adjustment Date following the Cut-off Date shall be the rate set forth in the Mortgage Loan Schedule as the Mortgage Rate in effect immediately following the Cut-off Date and (B) as of any date of determination thereafter shall be the rate as adjusted on the most recent Adjustment Date equal to the sum, rounded to the nearest or next highest 0.125% as provided in the Mortgage Note, of the Index, as most recently available as of a date prior to the Adjustment Date as set forth in the related Mortgage Note, plus the related Gross Margin; provided that the Mortgage Rate on such Adjustable-Rate Mortgage Loan on any Adjustment Date shall never be more than the lesser of (i) the sum of the Mortgage Rate in effect immediately prior to the Adjustment Date plus the related Periodic Rate Cap, if any, and (ii) the related Maximum Mortgage Rate, and shall never be less than the greater of (i) the Mortgage Rate in effect immediately prior to the Adjustment Date less the Periodic Rate Cap, if any, and (ii) the related Minimum Mortgage Rate. With respect to each Mortgage Loan that becomes an REO Property, as of any date of determination, the annual rate determined in accordance with the immediately preceding sentence as of the date such Mortgage Loan became an REO Property.

“Mortgaged Property”: The underlying property securing a Mortgage Loan, including any REO Property, consisting of an Estate in Real Property improved by a Residential Dwelling.

“Mortgagor”: The obligor on a Mortgage Note.

“Net Liquidation Proceeds”: With respect to any Liquidated Mortgage Loan or any other disposition of the related Mortgaged Property (including REO Property) the related Liquidation Proceeds and Insurance Proceeds net of Advances, Servicing Advances, Servicing Fees and any other accrued and unpaid servicing fees received and retained in connection with the liquidation of such Mortgage Loan or related Mortgaged Property and any amounts due on such Mortgage Loans on or prior to the Cut-off Date.

“Net Monthly Excess Cashflow”: With respect to each Distribution Date, the sum of (a) any Overcollateralization Release Amount for such Distribution Date and (b) the excess of (x) Available Funds for such Distribution Date over (y) the sum for such Distribution Date of (A) the Monthly Interest Distributable Amounts for the Class A Certificates and the Mezzanine Certificates, (B) the Unpaid Interest Shortfall Amounts for the Class A Certificates and (C) the Principal Remittance Amount.

“Net Mortgage Rate”: With respect to any Mortgage Loan (or the related REO Property) as of any date of determination, a per annum rate of interest equal to the then applicable Mortgage Rate for such Mortgage Loan minus the Servicing Fee Rate and the Master Servicer Fee Rate.

“Net Swap Payment”: In the case of payments made by the Trust, the excess, if any, of (x) the Fixed Swap Payment over (y) the Floating Swap Payment and in the case of payments made by the Swap Provider, the excess, if any, of (x) the Floating Swap Payment over (y) the Fixed Swap Payment. In each case, the Net Swap Payment shall not be less than zero.

“Net WAC Rate”: For any Distribution Date with respect to the Class A Certificates and the Mezzanine Certificates, a per annum rate equal to the product of (x) the weighted average of the Adjusted Net Mortgage Rates of the Mortgage Loans, weighted based on their outstanding Principal Balances as of the first day of the calendar month preceding the month in which the Distribution Date occurs minus (i) an amount, expressed as a percentage, equal to the product of (A) the Net Swap Payment, if any, paid by the Trust for such Distribution Date divided by the aggregate Stated Principal Balance of the Mortgage Loans and (B) 12 and (ii) an amount, expressed as a percentage, equal to the product of (A) the Swap Termination Payment, if any, due from the Trust (other than any Swap Termination Payment resulting from a Swap Provider Trigger Event) for such Distribution Date, divided by the aggregate Stated Principal Balance of the Mortgage Loans and (B) 12, and (y) a fraction, the numerator of which is 30 and the denominator of which is the actual number of days elapsed in the related Accrual Period.

“Net WAC Rate Carryover Amount”: With respect to the Class A Certificates and the Mezzanine Certificates and any Distribution Date, the sum of (A) the positive excess of (i) the amount of interest accrued on such Class of Certificates on such Distribution Date calculated at the related Formula Rate, over (ii) the amount of interest accrued on such Class of Certificates at the Net WAC Rate for such Distribution Date and (B) the Net WAC Rate Carryover Amount for the previous Distribution Date not previously paid, together with interest thereon at a rate equal to the Formula Rate for such Class of Certificates for such Distribution Date and for such Accrual Period.

“Net WAC Rate Carryover Reserve Account”: The account established and maintained pursuant to Section 4.07.

“New Lease”: Any lease of REO Property entered into on behalf of REMIC I, including any lease renewed or extended on behalf of REMIC I, if REMIC I has the right to renegotiate the terms of such lease.

“NIMS Insurer”: Any insurer that is guaranteeing certain payments under notes secured by collateral which includes all or a portion of the Class CE Certificates, the Class P Certificates, the Class R Certificates and/or the Class R-X Certificates.

“Nonrecoverable Advance”: Any Advance previously made or proposed to be made in respect of a Mortgage Loan or REO Property that, in the good faith business judgment of the related Servicer or the Master Servicer, as applicable, will not or, in the case of a proposed Advance, would not be ultimately recoverable from related Late Collections, Insurance Proceeds or Liquidation Proceeds on such Mortgage Loan or REO Property as provided herein.

“Nonrecoverable Servicing Advance”: Any Servicing Advance previously made or proposed to be made in respect of a Mortgage Loan or REO Property that, in the good faith business judgment of the related Servicer, will not or, in the case of a proposed Servicing Advance, would not be ultimately recoverable from related Late Collections, Insurance Proceeds or Liquidation Proceeds on such Mortgage Loan or REO Property as provided herein.

“Non-United States Person”: Any Person other than a United States Person.

“Notional Amount”: With respect to the Class CE Interest and any Distribution Date, the aggregate Uncertificated Balance of the REMIC II Regular Interests (other than REMIC II Regular Interest II-LTP) for such Distribution Date.

“Officer’s Certificate”: A certificate signed by the Chairman of the Board, the Vice Chairman of the Board, the President or a vice president (however denominated), and by the Treasurer, the Secretary, or one of the assistant treasurers or assistant secretaries of a Servicer, the Master Servicer, an Originator, the Seller or the Depositor, as applicable.

“One-Month LIBOR”: With respect to the Class A Certificates, the Mezzanine Certificates, REMIC II Regular Interest II-LTA1, REMIC II Regular Interest II-LTA2, REMIC II Regular Interest II-LTA3, REMIC II Regular Interest II-LTA4, REMIC II Regular Interest II-LTM1, REMIC II Regular Interest II-LTM2, REMIC II Regular Interest II-LTM3, REMIC II Regular Interest II-LTM4, REMIC II Regular Interest II-LTM5, REMIC II Regular Interest II-LTM6, REMIC II Regular Interest II-LTM7, REMIC II Regular Interest II-LTM8, REMIC II Regular Interest II-LTM9, REMIC II Regular Interest II-LTM10 and REMIC II Regular Interest II-LTM11 and any Accrual Period therefor, the rate determined by the Trust Administrator on the related Interest Determination Date on the basis of the offered rate for one-month U.S. dollar deposits, as such rate appears on Telerate Page 3750 as of 11:00 a.m. (London time) on such Interest Determination Date; provided that if such rate does not appear on Telerate Page 3750, the rate for such date will be determined on the basis of the offered rates of the Reference Banks for one-month U.S. dollar deposits, as of 11:00 a.m. (London time) on such Interest Determination Date. In such event, the Trust Administrator will request the principal London office of each of the Reference Banks to provide a quotation of its rate. If on such Interest Determination Date, two or more Reference Banks provide such offered quotations, One-Month LIBOR for the related Accrual Period shall be the arithmetic mean of such offered quotations (rounded upwards if necessary to the nearest whole multiple of 1/16%). If on such Interest Determination Date, fewer than two Reference Banks provide such offered quotations, One-Month LIBOR for the related Accrual Period shall be the higher of (i) One-Month LIBOR as determined on the previous Interest Determination Date and (ii) the Reserve Interest Rate. Notwithstanding the foregoing, if, under the priorities described above, One-Month LIBOR for an Interest Determination Date would be based on One-Month LIBOR for the previous Interest Determination Date for the third consecutive Interest Determination Date, the Trust Administrator shall select, after consultation with the NIMS Insurer, an alternative comparable index (over which the Trust Administrator has no control), used for determining one-month Eurodollar lending rates that is calculated and published (or otherwise made available) by an independent party.

“One-Year LIBOR” means the average of interbank offered rates for one-year U.S. dollar deposits in the London market based on quotations of major banks, and most recently available as of a day specified in the related mortgage note as published by the Western Edition of The Wall Street Journal .

“Opinion of Counsel”: A written opinion of counsel, who may, without limitation, be salaried counsel for the Depositor, the Seller, a Servicer or the Master Servicer, acceptable to the Trustee, if such opinion is delivered to the Trustee, or acceptable to the Trust Administrator, if such opinion is delivered to the Trust Administrator, except that any opinion of counsel relating to (a) the qualification of any Trust REMIC as a REMIC or (b) compliance with the REMIC Provisions must be an opinion of Independent counsel.

“Original Mortgage Loan”: Any of the Mortgage Loans included in REMIC I as of the Closing Date.

“Originator”: First NLC Financial Services, LLC, Meritage Mortgage Corporation, Decision One Mortgage Company, EquiFirst Corporation, Ownit Mortgage Solutions, Inc., First Street Financial, Inc. and LIME Financial Services, Ltd.

“Originator Master Agreements”: With respect to (i) First NLC Financial Services, LLC, the Master Seller’s Purchase, Warranties and Interim Servicing Agreement, dated as of February 1, 2006 between the Seller and First NLC Financial Services, LLC, as amended (ii) Meritage Mortgage Corporation; the Master Seller’s Purchase, Warranties and Interim Servicing Agreement, dated as of May 1, 2006, between the Seller and Meritage Mortgage Corporation, as amended, (iii) Decision One Mortgage Company, the Master Seller’s Purchase, Warranties and Interim Servicing Agreement, dated as of August 1, 2006, between the Seller and Decision One Mortgage Company (iv) EquiFirst Corporation, the Master Seller’s Purchase, Warranties and Interim Servicing Agreement, dated as of May 1, 2006, between the Seller and EquiFirst Corporation, as amended, (v) Ownit Mortgage Solutions, Inc., the Master Seller’s Purchase, Warranties and Interim Servicing Agreement, dated as of October 1, 2006, between the Seller and Ownit Mortgage Solutions, Inc. (vi) First Street Financial, Inc., the Master Seller’s Purchase, Warranties and Interim Servicing Agreement, dated as of August 1, 2004, between the Seller and First Street Financial, Inc., as amended and (vii) LIME Financial Services, Ltd., the Master Seller’s Purchase, Warranties and Interim Servicing Agreement, dated as of August 1, 2006 between the Seller and LIME Financial Services, Ltd.

“Originator Prepayment Charge Payment Amount”: The amounts payable by the Originator in respect of any waived Prepayment Charges pursuant to Section 3.01.

“Overcollateralization Deficiency Amount”: With respect to any Distribution Date, the amount, if any, by which the Overcollateralization Target Amount exceeds the Overcollateralized Amount on such Distribution Date (after giving effect to distributions in respect of the Principal Remittance Amount on such Distribution Date).

“Overcollateralization Release Amount”: With respect to any Distribution Date, the lesser of (x) the Principal Remittance Amount for such Distribution Date and (y) the Excess Overcollateralized Amount.  

“Overcollateralization Target Amount”: With respect to any Distribution Date, (i) 1.45 % of the Cut-off Date Principal Balance of the Mortgage Loans, (ii) on or after the Stepdown Date provided that a Trigger Event is not in effect, the greater of (x) 2.90% of the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) and (y) an amount equal to approximately 0.50% of the aggregate Stated Principal Balance of the Mortgage Loans as of the Cut-off Date, or (iii) on or after the Stepdown Date if a Trigger Event is in effect, the Overcollateralization Target Amount for the immediately preceding Distribution Date. On and after any Distribution Date following the reduction of the aggregate Certificate Principal Balance of the Class A Certificates and the Mezzanine Certificates to zero, the Overcollateralization Target Amount shall be zero.

“Overcollateralized Amount”: For any Distribution Date, the amount equal to (i) the aggregate Stated Principal Balance of the Mortgage Loans as of the last day of the related Due Period (after giving effect to scheduled payments of principal due during the related Due Period, to the extent received or advanced, and unscheduled collections of principal received during the related Prepayment Period) as of the related Determination Date minus (ii) the aggregate Certificate Principal Balance of the Class A Certificates, the Mezzanine Certificates and the Class P Certificates as of such Distribution Date after giving effect to distributions to be made on such Distribution Date.

“Ownership Interest”: As to any Certificate, any ownership or security interest in such Certificate, including any interest in such Certificate as the Holder thereof and any other interest therein, whether direct or indirect, legal or beneficial, as owner or as pledgee.

“Pass-Through Rate”: With respect to the Class A Certificates and the Mezzanine Certificates and any Distribution Date, a rate per annum equal to the lesser of (i) the related Formula Rate for such Distribution Date and (ii) the Net WAC Rate for such Distribution Date.

With respect to the Class CE Interest and any Distribution Date, a rate per annum equal to the percentage equivalent of a fraction, the numerator of which is (x) the sum of (i) 100% of the interest on REMIC II Regular Interest II-LTP and (ii) interest on the Uncertificated Balance of each REMIC II Regular Interest listed in clause (y) at a rate equal to the related REMIC II Remittance Rate minus the Marker Rate and the denominator of which is (y) the aggregate Uncertificated Balance of REMIC II Regular Interests II-LTAA, II-LTA1, II-LTA2, II-LTA3, II-LTA4, II-LTM1, II-LTM2, II-LTM3, II-LTM4, II-LTM5, II-LTM6, II-LTM7, II-LTM8, II-LTM9, II-LTM10, II-LTM11 and II-LTZZ.

With respect to the Class CE Certificates, 100% of the interest distributable to the Class CE Interest, expressed as a per annum rate.

With respect to the Class SWAP-IO Interest, the Class SWAP-IO Interest shall not have a Pass-Through Rate, but interest for such Regular Interest and each Distribution Date shall be an amount equal to 100% of the amounts distributable to REMIC II Regular Interest II-LTIO for such Distribution Date.

“Percentage Interest”: With respect to any Class of Certificates (other than the Residual Certificates), the undivided percentage ownership in such Class evidenced by such Certificate, expressed as a percentage, the numerator of which is the initial Certificate Principal Balance or Notional Amount represented by such Certificate and the denominator of which is the aggregate initial Certificate Principal Balance or Notional Amount of all of the Certificates of such Class. The Class A Certificates and the Mezzanine Certificates are issuable only in minimum Percentage Interests corresponding to minimum initial Certificate Principal Balances of $25,000 and integral multiples of $1.00 in excess thereof. The Class P Certificates are issuable only in Percentage Interests corresponding to initial Certificate Principal Balances of $20 and integral multiples thereof. The Class CE Certificates are issuable only in minimum Percentage Interests corresponding to minimum initial Certificate Principal Balances of $10,000 and integral multiples of $1.00 in excess thereof; provided, however, that a single Certificate of each such Class of Certificates may be issued having a Percentage Interest corresponding to the remainder of the aggregate initial Certificate Principal Balance or Notional Amount of such Class or to an otherwise authorized denomination for such Class plus such remainder. With respect to any Residual Certificate, the undivided percentage ownership in such Class evidenced by such Certificate, as set forth on the face of such Certificate. The Residual Certificates are issuable in Percentage Interests of 20% and multiples thereof.

“Periodic Rate Cap”: With respect to each Adjustable-Rate Mortgage Loan and any Adjustment Date therefor, the fixed percentage set forth in the related Mortgage Note, which is the maximum amount by which the Mortgage Rate for such Mortgage Loan may increase or decrease (without regard to the Maximum Mortgage Rate or the Minimum Mortgage Rate) on such Adjustment Date (other than the first Adjustment Date) from the Mortgage Rate in effect immediately prior to such Adjustment Date.

“Permitted Investments”: Any one or more of the following obligations or securities acquired at a purchase price of not greater than par, regardless of whether issued or managed by the Depositor, either Servicer, the Master Servicer, the NIMS Insurer, the Trustee, the Trust Administrator or any of their respective Affiliates or for which an Affiliate of the NIMS Insurer, the Trustee or the Trust Administrator serves as an advisor:

“Permitted Transferee”: Any Transferee of a Residual Certificate other than a Disqualified Organization or Non-United States Person.

“Person”: Any individual, corporation, partnership, limited liability company, joint venture, association, joint-stock company, trust, unincorporated organization or government or any agency or political subdivision thereof.

“Plan”: Any employee benefit plan or certain other retirement plans and arrangements, including individual retirement accounts and annuities, Keogh plans and bank collective investment funds and insurance company general or separate accounts in which such plans, accounts or arrangements are invested, that are subject to ERISA or Section 4975 of the Code.

“Prepayment Assumption”: As defined in the Prospectus Supplement.

“Prepayment Charge”: With respect to any Mortgage and Prepayment Period, any prepayment premium, fee, penalty or charge payable by a Mortgagor in connection with any full or partial Principal Prepayment on a Mortgage Loan pursuant to the terms of the related Mortgage Note and any Originator Prepayment Charge Payment Amount (other than any Servicer Prepayment Charge Payment Amount).

“Prepayment Charge Schedule”: As of any date, the list of Prepayment Charges on the Mortgage Loans provided by the Depositor included in REMIC I on such date, attached hereto as Schedule 2 (including the Prepayment Charge Summary attached thereto). The Prepayment Charge Schedule shall set forth the following information with respect to each related Mortgage Loan:

The Prepayment Charge Schedule shall be amended from time to time by the Depositor in accordance with the provisions of this Agreement and a copy of such amended Prepayment Charge Schedule shall be furnished by the Depositor to the NIMS Insurer and the related Servicer.

“Prepayment Interest Excess”: With respect to any Distribution Date, for each Mortgage Loan that was the subject of a Principal Prepayment in full during the portion of the related Prepayment Period commencing on the first day of the calendar month in which the Distribution Date occurs and ending on the last day of the related Prepayment Period, an amount equal to interest (to the extent received) at the applicable Net Mortgage Rate on the amount of such Principal Prepayment for the number of days commencing on the first day of the calendar month in which such Distribution Date occurs and ending on the date on which such prepayment is so applied.

“Prepayment Interest Shortfall”: With respect to any Distribution Date, for each Mortgage Loan that was the subject of a voluntary Principal Prepayment in full during the portion of the related Prepayment Period commencing on the first day of the related Prepayment Period and ending on the last day of the calendar month preceding the month in which such Distribution Date occurs, an amount equal to interest on the Mortgage Loan at the applicable Net Mortgage Rate on the amount of such Principal Prepayment for the number of days commencing on the date such Principal Prepayment was applied and ending on the last day of the calendar month preceding the month in which such Distribution Date occurs.

“Prepayment Period”: With respect to any Distribution Date and any Principal Prepayment in full and for any Mortgage Loan serviced by HomEq, the period commencing on the 16th day of the calendar month preceding the calendar month in which such Distribution Date occurs (or, in the case of the first Distribution Date, commencing on November 1, 2006) and ending on the 15th day of the calendar month in which such Distribution Date occurs. With respect to any Distribution Date and any Principal Prepayment in full and for any Mortgage Loan serviced by Wells Fargo, the period commencing on the 14th day of the calendar month preceding the calendar month in which such Distribution Date occurs (or, in the case of the first Distribution Date, commencing on November 1, 2006) and ending on the 13th day of the calendar month in which such Distribution Date occurs. With respect to any Distribution Date and any Principal Prepayment in part and for all the Mortgage Loans, the calendar month preceding the month in which the Distribution Date occurs.

“Present Value Maximum Probable Exposure”:   With respect to each   Distribution Date, the sum of each Present Value Probable Cash Flow from, and inclu