ASSIGNMENT, ASSUMPTION AND RECOGNITION AGREEMENT

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Exhibit 99.4

Execution Version

ASSIGNMENT, ASSUMPTION AND RECOGNITION AGREEMENT

This is an Assignment, Assumption and Recognition Agreement (this "AAR

Agreement") made as of July 1, 2007, among Merrill Lynch Mortgage Lending, Inc.,

having an address at 250 Vesey Street, 4 World Financial Center, 10th Floor, New

York, New York 10080 (the "Assignor"), Merrill Lynch Mortgage Investors, Inc.,

having an address at 250 Vesey Street, 4 World Financial Center, 10th Floor, New

York, New York 10080 (the "Assignee"), and IndyMac Bank, F.S.B., as seller (the

"Seller") and servicer (the "Servicer"), having an address at 3465 East Foothill

Boulevard, Pasadena, California 91107.

WHEREAS, the Assignor acquired the mortgage loans set forth on

Attachment 1 annexed hereto (the "Assigned Loans") from the Seller pursuant to

that certain Master Seller's Warranties and Servicing Agreement, dated as of May

1, 2006, between the Assignor and the Seller (the "Purchase and Servicing

Agreement");

In consideration of the mutual promises contained herein the parties

hereto agree that the Assigned Loans shall be subject to the terms of this AAR

Agreement. Capitalized terms used herein but not defined shall have the meanings

ascribed to them in the Purchase and Servicing Agreement.

Assignment and Assumption

1. Assignor hereby grants, transfers and assigns to Assignee all of the

right, title and interest of Assignor in the Assigned Loans and, as they relate

to the Assigned Loans, all of its right, title and interest in, to and under the

Purchase and Servicing Agreement. Assignor specifically reserves and does not

assign to Assignee any right, title and interest in, to or under any Mortgage

Loans subject to the Purchase and Servicing Agreement other than those set forth

on Attachment l. Notwithstanding anything to the contrary contained herein, the

Assignor is retaining the right to enforce the representations and warranties

made by the Seller and the Servicer prior to the date hereof with respect to the

Assigned Loans and the Seller and the Servicer.

Representations; Warranties and Covenants

2. Assignor warrants and represents to Assignee and Servicer as of the date

hereof:

a. Attached hereto as Attachment 2 is a true and accurate copy of the

Purchase and Servicing Agreement, which is in full force and effect as of the

date hereof and the provisions of which have not been waived, amended or

modified in any respect, nor has any notice of termination been given

thereunder;

b. Assignor was the lawful owner of the Assigned Loans with full right

to transfer the Assigned Loans and any and all of its interests, rights and

obligations under the Purchase and Servicing Agreement as it relates to the

Assigned Loans, free and clear of any and all liens, claims and encumbrances;

and upon the transfer of the Assigned Loans to Assignee as contemplated herein,

Assignee shall have good title to each and every Assigned Loan, as well as any

and all of Assignor's interests, rights and obligations under the Purchase and

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Agreement as it relates to the Assigned Loans, free and clear of any and all

liens, claims and encumbrances;

c. Assignor has not received notice of, and has no knowledge of, any

offsets, counterclaims or other defenses available to Servicer with respect to

the Assigned Loans or the Purchase and Servicing Agreement;

d. Assignor has not waived or agreed to any waiver under, or agreed to

any amendment or other modifications of, the Purchase and Servicing Agreement.

Assignor has no knowledge of, and has not received notice of, any waivers under

or any amendments or other modifications of, or assignment of rights or

obligations under the Purchase and Servicing Agreement;

e. Assignor is a corporation duly organized, validly existing and in

good standing under the laws of the jurisdiction of its formation, and has all

requisite power and authority to acquire, own and sell the Assigned Loans;

f. Assignor has full power and authority to execute, deliver and

perform its obligations under this AAR Agreement, and to consummate the

transactions set forth herein. The consummation of the transactions contemplated

by this AAR Agreement is in the ordinary course of Assignor's business and will

not conflict with, or result in a breach of, any of the terms, conditions or

provisions of Assignor's charter or by-laws or any legal restriction, or any

material agreement or instrument to which Assignor is now a party or by which it

is bound, or result in the violation of any law, rule, regulation, order,

judgment or decree to which Assignor or its property is subject. The execution,

delivery and performance by Assignor of this AAR Agreement and the consummation

by it of the transactions contemplated hereby, have been duly authorized by all

necessary action on the part of Assignor. This AAR Agreement has been duly

executed and delivered by Assignor and, upon the due authorization, execution

and delivery by Assignee and Servicer, will constitute the valid and legally

binding obligation of Assignor enforceable against Assignor in accordance with

its terms except as enforceability may be limited by bankruptcy, reorganization,

insolvency, moratorium or other similar laws now or hereafter in effect relating

to creditors' rights generally, and by general principles of equity regardless

of whether enforceability is considered in a proceeding in equity or at law;

g. No material consent, approval, order or authorization of, or

declaration, filing or registration with, any governmental entity is required to

be obtained or made by Assignor in connection with the execution, delivery or

performance by Assignor of this AAR Agreement, or the consummation by it of the

transactions contemplated hereby. Neither Assignor nor anyone acting on its

behalf has offered, transferred, pledged, sold or otherwise disposed of the

Assigned Loans or any interest in the Assigned Loans, or solicited any offer to

buy or accept transfer, pledge or other disposition of the Assigned Loans, or

any interest in the Assigned Loans, or otherwise approached or negotiated with

respect to the Assigned Loans, or any interest in the Assigned Loans, with any

Person in any manner, or made any general solicitation by means of general

advertising or in any other manner, or taken any other action which would

constitute a distribution of the Assigned Loans under the Securities Act of

1933, as amended (the "1933 Act") or which would render the disposition of the

Assigned Loans a violation of Section 5 of the 1933 Act or require registration

pursuant thereto; and

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h. Assignor has received from Seller, and has delivered to Assignee,

all documents required to be delivered to Assignor by Seller prior to the date

hereof pursuant to Section 2.01 of the Purchase and Servicing Agreement with

respect to the Assigned Loans.

3. Assignee warrants and represents to, and covenants with, Assignor and

Servicer as of the date hereof:

a. Assignee is a corporation duly organized, validly existing and in

good standing under the laws of the jurisdiction of its formation and has all

requisite power and authority to acquire, own and purchase the Assigned Loans;

b. Assignee has full power and authority to execute, deliver and

perform its obligations under this AAR Agreement, and to consummate the

transactions set forth herein. The consummation of the transactions contemplated

by this AAR Agreement is in the ordinary course of Assignee's business and will

not conflict with, or result in a breach of, any of the terms, conditions or

provisions of Assignee's charter or by-laws or any legal restriction, or any

material agreement or instrument to which Assignee is now a party or by which it

is bound, or result in the violation of any law, rule, regulation, order,

judgment or decree to which Assignee or its property is subject. The execution,

delivery and performance by Assignee of this AAR Agreement and the consummation

by it of the transactions contemplated hereby, have been duly authorized by all

necessary action on the part of Assignee. This AAR Agreement has been duly

executed and delivered by Assignee and, upon the due authorization, execution

and delivery by Assignor and Servicer, will constitute the valid and legally

binding obligation of Assignee enforceable against Assignee in accordance with

its terms except as enforceability may be limited by bankruptcy, reorganization,

insolvency, moratorium or other similar laws now or hereafter in effect relating

to creditors' rights generally, and by general principles of equity regardless

of whether enforceability is considered in a proceeding in equity or at law;

c. No material consent, approval, order or authorization of, or

declaration, filing or registration with, any governmental entity is required to

be obtained or made by Assignee in connection with the execution, delivery or

performance by Assignee of this AAR Agreement, or the consummation by it of the

transactions contemplated hereby;

d. There is no action, suit, proceeding, investigation or litigation

pending or, to Assignee's knowledge, threatened, which either in any instance or

in the aggregate, if determined adversely to Assignee, would adversely affect

Assignee's execution or delivery of, or the enforceability of, this AAR

Agreement, or the Assignee's ability to perform its obligations under this AAR

Agreement;

e. Assignee understands that the Assigned Loans have not been

registered under the 1933 Act or the securities laws of any state; and

f. Assignee is either (i) not an employee benefit plan that is subject

to the Employee Retirement Income Security Act of 1974, as amended ("ERISA"), or

Section 4975 of the Internal Revenue Code of 1986 (the "Code")(a "Plan") and not

a Person acting, directly or indirectly, on behalf of or investing with "plan

assets" of any such Plan or (ii) an employee benefit plan that is subject to

ERISA and the assignment contemplated herein does not constitute

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and will not result in non-exempt prohibited transaction under Section 406 of

ERISA or Section 4975 of the Code.

4. IndyMac Bank, F.S.B. ("IndyMac") warrants and represents to, and

covenants with, Assignor and Assignee that as of the date hereof:

a. IndyMac is a federal savings bank duly organized, validly existing

and in good standing under the laws of the United States;

b. IndyMac has full corporate power and authority to execute, deliver

and perform its obligations under this AAR Agreement, and to consummate the

transactions set forth herein. The consummation of the transactions contemplated

by this AAR Agreement is in the ordinary course of IndyMac's business and will

not conflict with, or result in a breach of, any of the terms, conditions or

provisions of IndyMac's charter or by-laws or any legal restriction, or any

material agreement or instrument to which IndyMac is now a party or by which it

is bound, or result in the violation of any law, rule, regulation, order,

judgment or decree to which IndyMac or its property is subject. The execution,

delivery and performance by IndyMac of this AAR Agreement and the consummation

by it of the transactions contemplated hereby, have been duly authorized by all

necessary corporate action on part of IndyMac. This AAR Agreement has been duly

executed and delivered by IndyMac and, upon the due authorization, execution and

delivery by Assignor and Assignee, will constitute the valid and legally binding

obligation of IndyMac enforceable against IndyMac in accordance with its terms

except as enforceability may be limited by bankruptcy, reorganization,

insolvency, moratorium or other similar laws now or hereafter in effect relating

to creditors' rights generally, and by general principles of equity regardless

of whether enforceability is considered in a proceeding in equity or at law; and

c. No consent, approval, order or authorization of, or declaration,

filing or registration with, any governmental entity is required to be obtained

or made by IndyMac in connection with the execution, delivery or performance by

IndyMac of this AAR Agreement, or the consummation by it of the transactions

contemplated hereby.

5. The Servicer hereby restates, as of the date hereof, the representations

and warranties contained in Section 3.02 of the Purchase and Servicing

Agreement, to and for the benefit of the Assignee, and by this reference

incorporates such representations and warranties herein, as of the date hereof

(other than with respect to the representations and warranties set forth in

Sections 3.02(b),(c)(m)(q)(z)(ii) and (ll) which are being made as of the

related Closing Date).

Recognition of Assignee

6. a. From and after the date hereof, the Servicer shall recognize the

Assignee as the owner of the Assigned Loans, and the Servicer will service the

Assigned Loans in accordance with the servicing provisions contained in the

Purchase and Servicing Agreement for the benefit of the Assignee, and shall look

solely to the Assignee for performance of the obligations of the Purchaser under

the Purchase and Servicing Agreement with respect to the Assigned Loans. The

Assignee hereby agrees and acknowledges that it shall uphold, or shall

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require its agents to uphold, the obligations of the Purchaser contained in the

Purchase and Servicing Agreement.

b. The Servicer acknowledges that Wells Fargo Bank, N.A. (the "Master

Servicer" and "Securities Administrator") has been appointed as the master

servicer of the Assigned Loans pursuant to the Pooling and Servicing Agreement,

dated as of July 1, 2007, by and among the Assignee, the Master Servicer, the

Securities Administrator and HSBC Bank USA, National Association (the "Pooling

and Servicing Agreement"). The Servicer shall deliver all reports required to be

delivered under the Purchase and Servicing Agreement to:

Wells Fargo Bank, N.A.

9062 Old Annapolis Road

Columbia, Maryland 21045

Attention: Merrill Lynch Mortgage Backed Securities Trust,

Series 2007-3

c. The Servicer hereby acknowledges that the Master Servicer has the

right to enforce all obligations of the Servicer under the Purchase and

Servicing Agreement acting on behalf of the Assignee, as owner of the Assigned

Loans. Such rights will include, without limitation, the right to terminate the

Servicer under the Purchase and Servicing Agreement upon the occurrence of an

event of default thereunder, the right to receive all remittances required to be

made by the Servicer under the Purchase and Servicing Agreement, the right to

receive all monthly reports and other data required to be delivered by the

Servicer under the Purchase and Servicing Agreement, the right to examine the

books and records of the Servicer and the right to exercise certain rights of

consent and approval relating to actions taken by the Assignor. The Master

Servicer shall be entitled to indemnification to the extent provided in Section

7A.07 and Article 9 of the Purchase and Servicing Agreement. Notwithstanding the

foregoing, it is understood that the Servicer shall not be obligated to defend

and indemnify and hold harmless the Master Servicer, the Assignee and the

Assignor from and against any losses, damages, penalties, fines, forfeitures,

judgments and any related costs including, without limitation, reasonable and

necessary legal fees, resulting from (i) actions or inactions of the Servicer

which were taken or omitted upon the instruction or direction of the Master

Servicer or (ii) the failure of the Master Servicer to perform its obligations

under the Purchase and Servicing Agreement, to the extent that the Master

Servicer has such obligations. In addition, the Assignee shall indemnify the

Servicer and hold it harmless against any and all claims, losses, damages,

penalties, fines, forfeitures, reasonable and necessary legal fees and related

costs, judgments, and any other costs, fees and expenses that the Servicer may

sustain in any way related to (a) actions or inactions of the Servicer which

were taken or omitted upon the instruction or direction of the Trustee or Master

Servicer, as applicable, or (b) the failure of the Trustee or the Master

Servicer, as applicable, to perform its obligations under the Purchase and

Servicing Agreement and this AAR Agreement.

The Servicer shall make all distributions under the Purchase and

Servicing Agreement to the Master Servicer by wire transfer of immediately

available funds to:

Wells Fargo Bank, N.A.

ABA Number: #121-000-248

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Account Name: Corporate Trust Clearing

Account number: 3970771416

For further credit to: MLMBS 2007-3

Distribution Account Number: 53168000

A copy of all assessments, attestations, reports and certifications required to

be delivered by the Servicer under this AAR Agreement and the Purchase and

Servicing Agreement shall be delivered to the Master Servicer by the date(s)

specified herein or therein, and where such documents are required to be

addressed to any party, such addressees shall include the Master Servicer and

the Master Servicer shall be entitled to rely on such documents.

d. The Servicer shall deliver all reports required to be delivered

under the Purchase and Servicing Agreement to the Master Servicer at the

following address:

Wells Fargo Bank, N.A.

9062 Old Annapolis Road

Columbia, Maryland 21045

Attention: Merrill Lynch Mortgage Backed Securities Trust,

Series 2007-3

Modification of the Purchase and Servicing Agreement

7. IndyMac is hereby notified, and IndyMac hereby acknowledges receipt of

such notification, that a REMIC election has been made with respect to the

Assigned Loans.

8. The Assignee and the Servicer hereby amend Article 1 of the Purchase and

Servicing Agreement, as it pertains to the Assigned Loans, by:

a. deleting the definition of "Business Day" in its entirety and

replacing it with the following:

"Business Day: Any day other than (i) a Saturday or Sunday, or (ii) a

day on which the Federal Reserve is closed, or (iii) a day on which banking

institutions in the jurisdiction in which the Master Servicer or the Servicer

are authorized or obligated by law or executive order to be closed.";

b. deleting clause (ii) of the definition of "Eligible Investments" in

its entirety and replacing it with the following:

"(ii) federal funds, demands and time deposits in, certificates of

deposits of, bankers' acceptances issued by or a segregated account maintained

with a federal or state chartered depository institution (A) the short-term

obligations of which are rated A-1 or better by S&P and P-1 by Moody's at the

time of any deposit therein or (B) the long term unsecured debt obligations of

which are rated at least "AA-" by S&P and "A+" by Fitch (if so rated) if the

deposits are to be held in the account more than 30 days; following a downgrade,

withdrawal, or suspension of such institution's rating, each account should

promptly (and in any case within not more than 30 calendar days) be moved to a

qualifying institution or to one or more segregated trust accounts in the trust

department of such institution, if permitted, (ii) a segregated trust

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account or accounts maintained with a federal or state chartered depository

institution or trust company with trust powers acting in its fiduciary capacity

or (iii) a segregated account or accounts of a depository institution acceptable

to the Rating Agencies (as evidenced by a letter from each Rating Agency that

use of any such account as the Custodial Account will not have an adverse effect

on the then-current ratings assigned to the Classes of the Certificates then

rated by the Rating Agencies). Eligible Accounts may bear interest.";

c. deleting the definition of "First Remittance Date" in its entirety

and replacing it with the following:

"First Remittance Date: August 18, 2007.";

d. deleting the definition of "Remittance Date" in its entirety and

replacing it with the following:

"Remittance Date: The 18th day (or if such 18th day is not a Business

Day, the preceding Business Day) of any month, beginning with the First

Remittance Date.";

e. deleting the definition of "Subservicer" in its entirety and

replacing it with the following:

"Subservicer: Any Person that services Mortgage Loans on behalf of the

Company or any Subservicer and is responsible for the performance (whether

directly or through Subservicers or Subcontractors) of a substantial portion of

the material servicing functions required to be performed by the Company under

this Agreement or any Reconstitution Agreement that are identified in Item

1122(d) of Regulation AB."; and

f. adding the following definitions in alphabetical order:

"Annual Independent Public Accountants' Servicing Report: A report of

a firm of independent public accountants which is a member of the American

Institute of Certified Public Accountants to the effect that such firm has

examined certain documents and records relating to the servicing of the Mortgage

Loans and that such firm is of the opinion that the provisions of this Agreement

have been complied with, and that, on the basis of such examination conducted

substantially in compliance with the Uniform Single Attestation Program for

Mortgage Bankers, nothing has come to the attention of such firm which would

indicate that such servicing has not been conducted in compliance therewith,

except (i) such exceptions such firm shall believe to be immaterial, and (ii)

such other exceptions as shall be set forth in such report. No Annual

Independent Public Accountants' Servicing Report shall contain any provision

restricting the use of such report by the Company, including any prohibition on

the inclusion of any such report in any filing with the Commission."

"Master Servicer: Wells Fargo Bank, N.A., or its successors in interest."

"Moody's: Moody's Investors Service, Inc., or its successors in interest."

"Reconstitution: Any Securitization Transaction or Whole Loan Transfer."

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"S&P: Standard & Poor's Rating Services, a division of The McGraw-Hill

Companies, or its successors in interest."

"Trustee: The party named as trustee in any agreement pursuant to a

Securitization Transaction."

9. The Assignee and the Servicer hereby amend the Purchase and Servicing

Agreement, as it pertains to the Assigned Loans, by:

a. deleting in its entirety the second sentence of the second

paragraph of Section 5.01 and replacing it with the following:

"Such interest shall be deposited in the Custodial Account by the

Company on the date such late payment is made and shall cover the period

commencing with the Business Day on which such payment is due and ending with

the Business Day on which such payment is made, both inclusive.";

b. adding the following language at the end of Section 5.02:

"In addition, no later than the tenth calendar day of each month, the

Company shall furnish to the Purchaser and the Master Servicer a file via

computer tape, email or modem containing, and a hard copy of, the monthly data

and the Company shall also furnish to the Purchaser and the Master Servicer a

report in the format set forth in Exhibit F, Exhibit G and Exhibit H attached

hereto, with respect to monthly remittance advice, defaulted Mortgage Loans and

Realized Loss Calculations.";

c. deleting in its entirety Section 6.04;

d. deleting in its entirety Section 6.05;

e. deleting in its entirety clause (ii) of Section 7A.03(e) and

replacing it with the following:

"(ii) which may be appointed as successor to the Company or any

Subservicer, the Company shall provide to the Purchase, any Master Servicer and

any Depositor, at least 15 calendar days prior to the effective date of such

succession or appointment, (x) written notice to the Purchase and any Depositor

of such succession or appointment and (y) in writing and in form and substance

reasonably satisfactory to the Purchase and such Depositor, all information

reasonably requested by the Purchase or any Depositor in order to comply with

the Depositor's reporting obligation under Item 6.02 of Form 8-K with respect to

any class of asset-backed securities.";

f. [Reserved];

g. delete in its entirety Section 7A.05(a)(iv) and replace it with