SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549
__________

FORM 10-K

FOR ANNUAL AND TRANSITION REPORTS

PURSUANT TO SECTIONS 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

(Mark One)

[X] ANNUAL REPORT PURSUANT TO SECTION 13 or 15(d) OF THE SECURITIES

EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2009

[ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
EXCHANGE ACT OF 1934

For the transition period from __________ to __________

Commission File Numbers 001-16443, 333-64879

MS STRUCTURED ASSET CORP.

On behalf of

SATURNS Trust No. 2003-3

(Exact name of registrant as specified in its charter)

Delaware 13-4026700

(State or other jurisdiction of incorporation or organization) (IRS Employer Identification No.)

1585 Broadway, Second Floor
New York, New York
Attention: In-Young Chase			10036
(Address of principal executive office)			(Zip Code)

Registrant’s telephone number, including area code: (212) 761-2520

Securities registered pursuant to Section 12(b) of the Act:

Title of Each Class

Name of Each Exchange on Which Registered

SATURNS Aon Capital Security Backed Series 2003-3
Class A Callable Units

New York Stock Exchange

Securities registered pursuant to Section 12(g) of the Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ___ No X

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. Yes ___ No X

Indicate by check mark whether registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes X No

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. [ ]

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer. See definition of “accelerated filer and large accelerated filer” in Rule 12b-2 of the Exchange Act. (Check one):

Large accelerated filer ___ Accelerated filer ___ Non-accelerated filer X

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes ___ No X

All of the common stock of the registrant is held by Morgan Stanley. As of March 19, 2010, 1,000 shares of common stock, par value $1.00 per share, were outstanding.

DOCUMENTS INCORPORATED BY REFERENCE:

The distribution reports to security holders filed on Form 8-K during the Fiscal Year in lieu of reports on Form 10-Q.

Introductory Note

The Registrant is the depositor under the trust agreements for it various SATURNS Units listed on the New York Stock Exchange. The Units do not represent obligations of or interests in the Depositor. Pursuant to staff administrative positions established in various no-action letters, see e.g. Corporate Asset Backed Corporation (available August 9, 1995), the Registrant is not required to respond to various items of Form 10-K. Such items are designated herein as “Not applicable.” Distribution reports detailing receipts and distributions by each trust are filed shortly after each distribution date on Form 8-K in lieu of reports on Form 10-Q.

The underlying security issuer or guarantor, as applicable, of the securities held by each of the trusts is subject to the informational requirements of the Exchange Act. The underlying security issuer or guarantor, as applicable, currently files reports, proxy statements and other information with the SEC. For information regarding such underlying security issuer or guarantor, you should refer to such reports. These periodic, current and other reports and other information can be inspected and copied at the public reference facilities maintained by the SEC at Room 1024, 100 F Street, N.E., Washington, D.C. 20549. Copies of those materials can be obtained by making a written request to the SEC, Public Reference Section, 100 F Street, N.E., Washington, D.C. 20549, at prescribed rates. The SEC also maintains a website on the internet at http://www.sec.gov at which users can view and download copies of reports, proxy, information statements and other information filed electronically. In addition, those reports and other information may also be obtained from the underlying security issuer by making a request to the underlying security issuer. The trust, the trustee, the Registrant, and their affiliates have not verified, have not undertaken to verify, and will not verify, the content of any such reports or information. The name and the central index key (CIK) for each underlying security issuer or guarantor is set forth below:

Trust	Underlying Security Issuer or Guarantor	CIK
2003-3	Aon Corporation	0000315293

PART I

ITEM 1. BUSINESS

Not Applicable

ITEM 1A. RISK FACTORS

Not Applicable

ITEM 1B. UNRESOLVED STAFF COMMENTS

None

ITEM 2. PROPERTIES

Not Applicable

ITEM 3. LEGAL PROCEEDINGS

None

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

None

PART II

ITEM 5. MARKET FOR REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDER MATTERS

The Units issued by the SATURNS trusts listed below representing investors’ interest in such trust are represented by one or more physical certificates registered in the name of Cede & Co., the nominee of The Depository Trust Company. These Units are listed on the New York Stock Exchange:

SATURNS Trust No. 2003-3 Class A Units (Aon Capital Security Backed)

ITEM 6. SELECTED FINANCIAL DATA

Not Applicable

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

Not Applicable

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Not Applicable

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

Not Applicable

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE

None

ITEM 9A. CONTROLS AND PROCEDURES

Not Applicable

ITEM 9B. OTHER INFORMATION

None

PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

None

ITEM 11. EXECUTIVE COMPENSATION

Not Applicable

Item 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

None

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

None

ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES

Not Applicable

PART IV

ITEM 15. EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K

(a) The following documents are filed as part of this Report: None

(b) Reports on Form 8-K:

See Table Below:

SATURNS Trust No.:

Closing Date

Payment Dates

Form 8-K Filing Dates (Not Trust Agreement Filings in connection with Closing Date)

For FY 2009

2003-3

2/27/03

January 2 and July 1

January 8, 2009 and July 6, 2009

SATURNS Trust No.:

Closing Date

Event Description

Form 8-K Filing Dates (Not Trust Agreement Filings in connection with Closing Date or filings related to Payment Dates)

For FY 2009

2003-3

2/27/03

Bank of America, N.A. as successor by merger to LaSalle Bank N.A. acts as trustee for the issuing entity.

On November 25, 2009, Bank of America, N.A. (BANA) was named as a defendant in two related lawsuits filed in the U.S. District Court for the Southern District of New York. In BNP Paribas Mortgage Corporation v. Bank of America, N.A. and Deutsche Bank, AG v. Bank of America, N.A., plaintiffs assert breach of contract, negligence, and indemnification claims in connection with BANA's roles as, among other things, collateral agent, custodian, and indenture trustee of Ocala Funding, LLC (Ocala). Ocala was a mortgage warehousing facility that provided funding to Taylor, Bean & Whitaker Mortgage Corp. (TBW) by issuing commercial paper and term securities backed by mortgage loans originated by TBW. Plaintiffs claim that they purchased in excess of $1.6 billion in securities issued by Ocala and that BANA allegedly failed, among other things, to protect the collateral backing plaintiffs' securities. Plaintiffs seek unspecified compensatory damages, among other relief.

December 30, 2009

Exhibit 31.1 Rule 13a-14(d) Certification

Exhibit 31.2 Trustee Compliance Certification

The trust covered by this annual report was formed prior to June 30, 2003 and there is no requirement in the trust agreement for the preparation of a report by an independent public accountant regarding the trustee’s compliance with its obligations.

(d) Not applicable

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: March 24, 2010

MS STRUCTURED ASSET CORP.
(Registrant)

By: /s/In-Young Chase

Name: In-Young Chase

Title: Vice President

Exhibit 31.1

Rule 13a-14(d) Certification

I, In-Young Chase, certify that:

1. I have reviewed this annual report on Form 10-K, and all reports on Form 8-K containing distribution or servicing reports filed in respect of periods included in the year covered by this annual report, of MS Structured Asset Corp. on behalf of SATURNS Trust No. 2003-3;

2. Based on my knowledge, the information in these reports, taken as a whole, does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading as of the last day of the period covered by this annual report;

3. Based on my knowledge, the distribution or servicing information required to be provided to the depositor by the trustee under the pooling and servicing, or similar, agreement, for inclusion in these reports is included in these reports; and

4. I am responsible for reviewing the activities performed by the depositor and the trustee under the pooling and servicing, or similar, agreement and based upon my knowledge and the annual compliance review required under that agreement, and except as disclosed in the reports, the depositor and trustee have each fulfilled its obligations under that agreement.

In giving the certifications above, I have reasonably relied on information provided to me by the following unaffiliated parties: Bank of America, National Association as successor by merger to LaSalle Bank National Association and its officers and agents.

By: /s/In-Young Chase

Name: In-Young Chase

Title: Vice President

Date: March 24, 2010

Exhibit 31.2

COMPLIANCE STATEMENT

In connection with the preparation and delivery of the annual report on Form 10-K of MS Structured Asset Corp. on behalf of SATURNS Trust No. 2003-3 for the fiscal year ending December 31, 2009, and the certifications given by In-Young Chase with respect thereto, the undersigned hereby certifies that he is a duly elected Senior Vice President of Bank of America, National Association as successor by merger to LaSalle Bank National Association and further certifies in his capacity as such as follows:

1. Bank of America, National Association as successor by merger to LaSalle Bank National Association has prepared all distribution reports with respect to each distribution date for SATURNS Trust No. 2003-3, and has filed a copy of such reports on Form 8-K during the fiscal year as described on Exhibit A hereto.

2. I have reviewed all reports on Form 8-K containing distribution reports filed in respect of periods included in the fiscal year covered by the annual report of MS Structured Asset Corp. on behalf of SATURNS Trust No. 2003-3;

3. I am familiar with the operations of Bank of America, National Association as successor by merger to LaSalle Bank National Association with respect to the SATURNS program and SATURNS Trust No. 2003-3 and the requirement imposed by the applicable trust agreement;

4. Based on my knowledge, the information in the distribution reports, taken as a whole, does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading as of the last day of the period covered by the annual report;

5. Based on my knowledge, the information required to be provided under each trust agreement, for inclusion in the distribution reports, is included in the distribution reports;

6. Based on my knowledge, and except as disclosed in the distribution reports, the trustee has fulfilled its obligations, including any servicing obligations, under the trust agreement.

7. Based on my knowledge, and except as disclosed in the distribution reports and as disclosed on the 8-K filed on December 30, 2009 and referenced on Exhibit A to this compliance certificate, there are no material legal proceedings with respect to any trust, involving the trust or Bank of America, National Association as successor by merger to LaSalle Bank National Association as trustee.

By: /s/Thomas M. O'Connor_____

Name: Thomas M. O'Connor

Title: Senior Vice President

Date: March 24, 2010

EXHIBIT A

SATURNS Trust No.:

Closing Date

Payment Dates

Form 8-K Filing Dates (Not Trust Agreement Filings in connection with Closing Date)

For FY 2009

2003-3

2/27/03

January 2 and July 1

January 8, 2009 and July 6, 2009

SATURNS Trust No.:

Closing Date

Event Description

Form 8-K Filing Dates (Not Trust Agreement Filings in connection with Closing Date or filings related to Payment Dates)

For FY 2009

2003-3

2/27/03

Bank of America, N.A. as successor by merger to LaSalle Bank N.A. acts as trustee for the issuing entity.

December 30, 2009

MS STRUCTURED SATURNS SERIES 2003-3 10-K