MORTGAGE LOAN SALE AND ASSIGNMENT AGREEMENT

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EXHIBIT 99.1

EXECUTION COPY

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LEHMAN BROTHERS HOLDINGS INC.,

SELLER

and

STRUCTURED ASSET SECURITIES CORPORATION,

PURCHASER

MORTGAGE LOAN SALE AND ASSIGNMENT AGREEMENT

Dated as of February 1, 2005

Structured Adjustable Rate Mortgage Loan Trust

(Mortgage Pass-Through Certificates, Series 2005-4)

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TABLE OF CONTENTS

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PAGE

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ARTICLE I

CONVEYANCE OF MORTGAGE LOANS

Section 1.01. Mortgage Loans................................................3

Section 1.02. Delivery of Documents.........................................4

Section 1.03. Review of Documentation.......................................4

Section 1.04. Representations and Warranties of the Seller..................4

Section 1.05. Grant Clause.................................................13

Section 1.06. Assignment by Depositor......................................13

ARTICLE II

MISCELLANEOUS PROVISIONS

Section 2.01. Binding Nature of Agreement; Assignment......................14

Section 2.02. Entire Agreement.............................................14

Section 2.03. Amendment....................................................14

Section 2.04. Governing Law................................................15

Section 2.05. Severability of Provisions...................................15

Section 2.06. Indulgences; No Waivers......................................15

Section 2.07. Headings Not to Affect Interpretation........................15

Section 2.08. Benefits of Agreement........................................15

Section 2.09. Counterparts.................................................15

SCHEDULE

SCHEDULE A Mortgage Loan Schedule

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This MORTGAGE LOAN SALE AND ASSIGNMENT AGREEMENT, dated as of February

1, 2005 (the "Agreement"), is executed by and between Lehman Brothers Holdings

Inc. (the "Seller") and Structured Asset Securities Corporation (the

"Depositor").

All capitalized terms not defined herein shall have the same meanings

assigned to such terms in that certain Trust Agreement (the "Trust Agreement"),

dated as of February 1, 2005, among the Depositor, Aurora Loan Services LLC, as

master servicer ("Aurora"), Wells Fargo Bank, National Association, as

securities administrator (the "Securities Administrator"), and HSBC Bank USA,

National Association, as trustee (the "Trustee").

W I T N E S S E T H:

WHEREAS, Lehman Brothers Bank, FSB (the "Bank"), pursuant to the

following specified agreements (each, a "Bank Transfer Agreement" and

collectively, the "Transfer Agreements"), has purchased or received certain

mortgage loans identified on the Mortgage Loan Schedule attached hereto as

Schedule A-1 (each, a "Bank Transferred Mortgage Loan" and collectively, the

"Transferred Mortgage Loans"):

1. Flow Seller's Warranties and Servicing Agreement, dated as of

June 1, 2004, by and between the Bank and Countrywide Home

Loans, Inc. ("Countrywide");

2. Seller's Warranties and Servicing Agreement, dated as of July

1, 2003, by and between the Bank and IndyMac Bank, F.S.B.

("IndyMac");

3. Loan Purchase Agreement, dated as of May 9, 2002, by and

between the Bank and Sierra Pacific Mortgage Company, Inc.

("Sierra Pacific");

4. Flow Purchase, Warranties and Servicing Agreement dated as of

July 1, 2004, by and between the Bank and Wachovia Mortgage

Corporation ("Wachovia")

5. Seller's Warranties and Servicing Agreement, dated as of

September 1, 2004, by and between the Bank and Wells Fargo

Home Mortgage, Inc. ("Wells Fargo").

WHEREAS, in addition to the Bank Transferred Mortgage Loans, the Bank

has funded certain mortgage loans originated by Aurora Loan Services Inc.

identified on the Mortgage Loan Schedule attached hereto as Schedule A-2 (each,

a "Bank Originated Mortgage Loan" and together with the Bank Transferred

Mortgage Loans, the "Bank Mortgage Loans" or the "Mortgage Loans");

WHEREAS, pursuant to an Assignment and Assumption Agreement (the

"Assignment and Assumption Agreement"), dated as of February 1, 2005, between

the Bank, as assignor, and the Seller, as assignee, the Bank has assigned all of

its right, title and interest in and to the Bank Transfer Agreements and related

Mortgage Loans as listed on Schedule A-1, in the case of the Bank Transferred

Mortgage Loans, or Schedule A-2, in the case of the Bank Originated Mortgage

Loans, and the Seller has accepted the rights and benefits of, and assumed the

obligations of the Bank under, the Bank Transfer Agreements;

WHEREAS, the Seller is a party to the following servicing agreements

(collectively, the "Servicing Agreement") pursuant to which the Mortgage Loans

are serviced by Aurora,

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Countrywide, IndyMac, Sierra Pacific, Wachovia, and Wells Fargo (each as a

servicer, a "Servicer" and collectively, the "Servicers"):

1. Flow Seller's Warranties and Servicing Agreement, dated as of

June 1, 2004, by and between the Bank and Countrywide Home

Loans, Inc.;

2. Reconstituted Servicing Agreement, dated as of February 1,

2005, by and between the Seller and Countrywide;

3. Flow Purchase, Warranties and Servicing Agreement, dated as of

July 1, 2003, by and between the Bank and IndyMac;

4. Reconstituted Servicing Agreement, dated as of February 1,

2005, by and between the Seller and IndyMac;

5. Loan Purchase Agreement, dated as of May 9, 2002, by and

between the Bank and Sierra Pacific

6. Reconstituted Servicing Agreement, dated as of February 1,

2005, by and between the Seller and Sierra Pacific;

7. Flow Purchase Warranties and Servicing Agreement, dated as of

July 1, 2004, by and between the Bank and Wachovia;

8. Reconstituted Servicing Agreement, dated as of February 1,

2005, by and between the Seller and Wachovia;

9. Seller's Warranties and Servicing Agreement, dated as of

September 1, 2004, by and between the Bank and Wells Fargo;

10. Reconstituted Servicing Agreement, dated as of February 1,

2005, by and between the Seller and Wells Fargo;

WHEREAS, the Seller desires to sell, without recourse, all of its

rights, title and interest in and to the Mortgage Loans (exclusive of any

Retained Interest on such Mortgage Loans) to the Depositor and to assign all of

its rights and interest under the Transfer Agreements and the Servicing

Agreements relating to the Mortgage Loans, and to delegate all of its

obligations thereunder, to the Depositor; and

WHEREAS, the Seller and the Depositor acknowledge and agree that the

Depositor will convey the Mortgage Loans to a Trust Fund created pursuant to the

Trust Agreement, assign all of its rights and delegate all of its obligations

hereunder to the Trustee for the benefit of the Certificateholders, and that

each reference herein to the Depositor is intended, unless otherwise specified,

to mean the Depositor or the Trustee, as assignee, whichever is the owner of the

Mortgage Loans from time to time.

NOW, THEREFORE, in consideration of the mutual agreements herein set

forth, and for other good and valuable consideration, the receipt and adequacy

of which are hereby acknowledged, the Seller and the Depositor agree as follows:

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ARTICLE I

CONVEYANCE OF MORTGAGE LOANS

Section 1.01. Mortgage Loans.

(a) Sale of Mortgage Loans. Concurrently with the execution and

delivery of this Agreement, the Seller does hereby transfer, assign, set over,

deposit with and otherwise convey to the Depositor, without recourse, subject to

Sections 1.03 and 1.04, all the right, title and interest of the Seller in and

to the Mortgage Loans (exclusive of any Retained Interest on such Mortgage

Loans, if any) identified on Schedule A-1 and Schedule A-2 hereto, having an

aggregate principal balance as of the Cut-off Date of $929,492,496.62. Such

conveyance includes, without limitation, the right to all distributions of

principal and interest received on or with respect to the Mortgage Loans on or

after February 1, 2005 other than (i) any amounts representing Retained

Interest, if any, and (ii) payments of principal and interest due on or before

such date, and all such payments due after such date but received prior to such

date and intended by the related Mortgagors to be applied after such date,

together with all of the Seller's right, title and interest in and to each

related account and all amounts from time to time credited to and the proceeds

of such account, any REO Property and the proceeds thereof, the Seller's rights

under any Insurance Policies relating to the Mortgage Loans, the Seller's

security interest in any collateral pledged to secure the Mortgage Loans,

including the Mortgaged Properties, and any proceeds of the foregoing.

(b) Concurrently with the execution and delivery of this Agreement, the

Seller hereby assigns to the Depositor all of its rights and interest under each

Transfer Agreement and each Servicing Agreement, other than any right to receive

Retained Interest if any, and any servicing rights retained thereunder, and

delegates to the Depositor all of its obligations thereunder, to the extent

relating to the Mortgage Loans. The Seller and the Depositor further agree that

this Agreement incorporates the terms and conditions of any assignment and

assumption agreement or other assignment document required to be entered into

under any of the Transfer Agreements (any such document an "Assignment

Agreement") and this Agreement constitutes an Assignment Agreement under such

Transfer Agreement, and the Depositor hereby assumes the obligations of the

assignee under each such Assignment Agreement. Concurrently with the execution

hereof, the Depositor tenders the purchase price of $929,492,496.62. The

Depositor hereby accepts such assignment and delegation, and shall be entitled

to exercise all the rights of the Seller under each Transfer Agreement and each

Servicing Agreement, other than any servicing rights thereunder, as if the

Depositor had been a party to each such agreement.

(c) Schedules of Mortgage Loans. The Depositor and the Seller have

agreed upon which of the Mortgage Loans owned by the Seller are to be purchased

by the Depositor pursuant to this Agreement and the Seller will prepare on or

prior to the Closing Date a final schedule describing such Mortgage Loans (the

"Mortgage Loan Schedule"). The Mortgage Loan Schedule shall conform to the

requirements of the Depositor as set forth in this Agreement and to the

definition of "Mortgage Loan Schedule" under the Trust Agreement. The Mortgage

Loan Schedule attached hereto as Schedule A-1 specifies those Mortgage Loans

that are Transferred Mortgage Loans and the Mortgage Loan Schedule attached

hereto as Schedule A-2 specifies

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those Mortgage Loans that are Bank Originated Mortgage Loans and which have been

assigned by the Bank to the Seller pursuant to the Assignment and Assumption

Agreement.

Section 1.02. Delivery of Documents.

(a) In connection with such transfer and assignment of the Mortgage

Loans hereunder, the Seller, shall, at least three (3) Business Days prior to

the Closing Date, deliver, or cause to be delivered, to the Depositor (or its

designee) the documents or instruments with respect to each Mortgage Loan (each

a "Mortgage File") so transferred and assigned, as specified in the related

Transfer Agreements or Servicing Agreements.

(b) For Mortgage Loans (if any) that have been prepaid in full on or

after the Cut-off Date and prior to the Closing Date, the Seller, in lieu of

delivering the related Mortgage Files, herewith delivers to the Depositor an

Officer's Certificate which shall include a statement to the effect that all

amounts received in connection with such prepayment that are required to be

deposited in the Collection Account maintained by the Master Servicer for such

purpose have been so deposited.

Section 1.03. Review of Documentation. The Depositor, by execution

and delivery hereof, acknowledges receipt of the Mortgage Files pertaining to

the Mortgage Loans listed on the Mortgage Loan Schedule, subject to review

thereof by the custodian, LaSalle Bank National Association, U.S. Bank National

Association and Wells Fargo Bank, National Association, as applicable (each, a

"Custodian" and together, the "Custodians"), for the Depositor. Each Custodian

is required to review, within 45 days following the Closing Date, each

applicable Mortgage File. If in the course of such review the related Custodian

identifies any Material Defect, the Seller shall be obligated to cure such

Material Defect or to repurchase the related Mortgage Loan from the Depositor

(or, at the direction of and on behalf of the Depositor, from the Trust Fund),

or to substitute a Qualifying Substitute Mortgage Loan therefor, in each case to

the same extent and in the same manner as the Depositor is obligated to the

Trustee and the Trust Fund under Section 2.02(c) of the Trust Agreement.

Section 1.04. Representations and Warranties of the Seller.

(a) The Seller hereby represents and warrants to the Depositor that as

of the Closing Date:

(i) The Seller is a corporation duly organized, validly

existing and in good standing under the laws governing its creation and

existence and has full corporate power and authority to own its

property, to carry on its business as presently conducted, and to enter

into and perform its obligations under this Agreement and the

Assignment and Assumption Agreement;

(ii) The execution and delivery by the Seller of this

Agreement and the Assignment and Assumption Agreement have been duly

authorized by all necessary corporate action on the part of the Seller;

neither the execution and delivery of this Agreement or the Assignment

and Assumption Agreement, nor the consummation of the transactions

herein or therein contemplated, nor compliance with the provisions

hereof or thereof, will conflict with or result in a breach of, or

constitute a default under, any of the

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provisions of any law, governmental rule, regulation, judgment, decree

or order binding on the Seller or its properties or the certificate of

incorporation or bylaws of the Seller;

(iii) The execution, delivery and performance by the Seller of

this Agreement and the Assignment and Assumption Agreement and the

consummation of the transactions contemplated hereby and thereby do not

require the consent or approval of, the giving of notice to, the

registration with, or the taking of any other action in respect of, any

state, federal or other governmental authority or agency, except such

as has been obtained, given, effected or taken prior to the date

hereof;

(iv) Each of this Agreement and the Assignment and Assumption

Agreement has been duly executed and delivered by the Seller and,

assuming due authorization, execution and delivery by the Bank, in the

case of the Assignment and Assumption Agreement, and the Depositor, in

the case of this Agreement, constitutes a valid and binding obligation

of the Seller enforceable against it in accordance with its respective

terms, except as such enforceability may be subject to (A) applicable

bankruptcy and insolvency laws and other similar laws affecting the

enforcement of the rights of creditors generally and (B) general

principles of equity regardless of whether such enforcement is

considered in a proceeding in equity or at law; and

(v) There are no actions, suits or proceedings pending or, to

the knowledge of the Seller, threatened or likely to be asserted

against or affecting the Seller, before or by any court, administrative

agency, arbitrator or governmental body (A) with respect to any of the

transactions contemplated by this Agreement or the Assignment and

Assumption Agreement or (B) with respect to any other matter which in

the judgment of the Seller will be determined adversely to the Seller

and will if determined adversely to the Seller materially and adversely

affect it or its business, assets, operations or condition, financial

or otherwise, or adversely affect its ability to perform its

obligations under this Agreement or the Assignment and Assumption

Agreement.

(b) The representations and warranties of each Transferor with respect

to the Transferred Mortgage Loans in the applicable Transfer Agreement were made

as of the date of such Transfer Agreement. To the extent that any fact,

condition or event with respect to a Transferred Mortgage Loan constitutes a

breach of both (i) a representation or warranty of a Transferor under the

applicable Transfer Agreement and (ii) a representation or warranty of the

Seller under this Agreement, the sole right or remedy of the Depositor with

respect to a breach by the Seller of such representation and warranty (other

than a breach by the Seller of the representations and warranties made pursuant

to Sections 1.04(b)(xii), 1.04(b)(xvii), 1.04(b)(xviii), 1.04(b)(xix),

1.04(b)(xx) and (1.04)(b)(xxi)) shall be the right to enforce the obligations of

such Transferor under any applicable representation or warranty made by it. The

representations made by the Seller pursuant to Sections 1.04(b)(xii),

1.04(b)(xvii), 1.04(b)(xviii), 1.04(b)(xix), 1.04(b)(xx) and 1.04(b)(xxi) shall

be direct obligations of the Seller. The Depositor acknowledges and agrees that

the representations and warranties of the Seller in this Section 1.04(b) (other

than the representations and warranties made pursuant to Sections 1.04(b)(xii),

1.04(b)(xvii), 1.04(b)(xviii), 1.04(b)(xix), 1.04(b)(xx) and 1.04(b)(xxi)) are

applicable only to facts, conditions or events that do not constitute a breach

of any representation or warranty made by the related Transferor in the

applicable Transfer Agreement. The Seller shall have no

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obligation or liability with respect to any breach of a representation or

warranty made by it with respect to the Transferred Mortgage Loans if the fact,

condition or event constituting such breach also constitutes a breach of a

representation or warranty made by the related Transferor in such Transfer

Agreement, without regard to whether the related Transferor fulfills its

contractual obligations in respect of such representation or warranty; provided,

however, that if the related Transferor fulfills its obligations under the

provisions of such Transfer Agreement by substituting for the affected Mortgage

Loan a mortgage loan which is not a Qualifying Substitute Mortgage Loan, the

Seller shall, in exchange for such substitute mortgage loan, provide the

Depositor (a) with the applicable Purchase Price for the affected Mortgage Loan

or (b) within the two-year period following the Closing Date, with a Qualified

Substitute Mortgage Loan for such affected Transferred Mortgage Loan. Subject to

the foregoing, the Seller represents and warrants upon delivery of the

Transferred Mortgage Loans to the Depositor hereunder on the Closing Date, as to

each, that:

(i) The information set forth with respect to the Transferred

Mortgage Loans on the Mortgage Loan Schedule provides an accurate

listing of the Transferred Mortgage Loans, and the information with

respect to each Transferred Mortgage Loan on the Mortgage Loan Schedule

is true and correct in all material respects at the date or dates

respecting which such information is given;

(ii) There are no defaults (other than delinquency in payment)

in complying with the terms of any Mortgage, and the Seller has no

notice as to any taxes, governmental assessments, insurance premiums,

water, sewer and municipal charges, leasehold payments or ground rents

which previously became due and owing but which have not been paid;

(iii) Except in the case of Cooperative Loans, if any, each

Mortgage requires all buildings or other improvements on the related

Mortgaged Property to be insured by a generally acceptable insurer

against loss by fire, hazards of extended coverage and such other

hazards as are customary in the area where the related Mortgaged

Property is located pursuant to insurance policies conforming to the

requirements of the guidelines of FNMA or FHLMC. If upon origination of

the Transferred Mortgage Loan, the Mortgaged Property was in an area

identified in the Federal Register by the Federal Emergency Management

Agency as having special flood hazards (and such flood insurance has

been made available) a flood insurance policy meeting the requirements

of the current guidelines of the Federal Flood Insurance Administration

is in effect which policy conforms to the requirements of the current

guidelines of the Federal Flood Insurance Administration. Each Mortgage

obligates the related Mortgagor thereunder to maintain the hazard

insurance policy at the Mortgagor's cost and expense, and on the

Mortgagor's failure to do so, authorizes the holder of the Mortgage to

obtain and maintain such insurance at such Mortgagor's cost and

expense, and to seek reimbursement therefor from the Mortgagor. Where

required by state law or regulation, each Mortgagor has been given an

opportunity to choose the carrier of the required hazard insurance,

provided the policy is not a "master" or "blanket" hazard insurance

policy covering the common facilities of a planned unit development.

The hazard insurance policy is the valid and binding obligation of the

insurer, is in full force and

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effect, and will be in full force and effect and inure to the benefit

of the Depositor upon the consummation of the transactions contemplated

by this Agreement;

(iv) Each Mortgage has not been satisfied, cancelled,

subordinated or rescinded, in whole or in part, and the Mortgaged

Property has not been released from the lien of the Mortgage, in whole

or in part, nor has any instrument been executed that would effect any

such release, cancellation, subordination or rescission;

(v) Each Mortgage evidences a valid, subsisting, enforceable

and perfected first lien on the related Mortgaged Property (including

all improvements on the Mortgaged Property). The lien of th