# EDGAR Filing Document

**Accession Number:** 0000806564
**File Stem:** 0001104659-25-056831
**Filing Date:** 2025-6
**Character Count:** 3240
**Document Hash:** 5bc23b1e0029545e1b06663d6453f59a
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-25-056831.hdr.sgml**: 20250605

**ACCESSION NUMBER**: 0001104659-25-056831

**CONFORMED SUBMISSION TYPE**: DEFA14A

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20250605

**DATE AS OF CHANGE**: 20250605

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MORGAN STANLEY MORTGAGE SECURITIES TRUST
- **CENTRAL INDEX KEY:** 0000806564

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 1031

**FILING VALUES:**
- **FORM TYPE:** DEFA14A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 811-04917
- **FILM NUMBER:** 251027181

**BUSINESS ADDRESS:**
- **STREET 1:** 1585 BROADWAY
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10036
- **BUSINESS PHONE:** 800-869-6397

**MAIL ADDRESS:**
- **STREET 1:** 1585 BROADWAY
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10036

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MORGAN STANLEY FEDERAL SECURITIES TRUST
- **DATE OF NAME CHANGE:** 20010618

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MORGAN STANLEY DEAN WITTER FEDERAL SECURITIES TRUST
- **DATE OF NAME CHANGE:** 19980622

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** WITTER DEAN FEDERAL SECURITIES TRUST
- **DATE OF NAME CHANGE:** 19930210

## Series and Classes Contracts Data

### Morgan Stanley Mortgage Securities Trust (Series ID: S000002467)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000006611 | A            | MTGAX           |
| C000006613 | L            | MTGCX           |
| C000006614 | I            | MTGDX           |
| C000155975 | Class C      | MSMTX           |
| C000198813 | Class R6     | MORGX           |

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**SCHEDULE 14A**

**Proxy Statement Pursuant to Section 14(a) of the**

**Securities Exchange Act of 1934 (Amendment No.)**

Filed by the Registrant ⌧

Filed by a Party other than the Registrant ◻

Check the appropriate box:

◻ Preliminary Proxy Statement

◻ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

◻ Definitive Proxy Statement

⌧ Definitive Additional Materials

◻ Soliciting Material Under Rule 14a-12

MORGAN STANLEY MORTGAGE SECURITIES TRUST

(Name of Registrant as Specified In Its Charter)

Payment of Filing Fee (Check the appropriate box):

⌧ No fee required.

◻ Fee paid previously with preliminary materials.

◻ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

**June 5, 2025**

**MORGAN STANLEY MORTGAGE SECURITIES TRUST**

c/o Morgan Stanley Investment Management Inc.

1585 Broadway

New York, New York 10036

**Notice of Adjournment of Special Meeting of Shareholders**

The Special Meeting of Shareholders of Morgan Stanley Mortgage Securities Trust initially held on June 5, 2025, was adjourned to June 11, 2025, at 3:00 p.m. Eastern time due to a lack of voter participation. The meeting will be held at 1585 Broadway, 27<sup>th</sup> Floor, Room D, New York, NY 10036. Please contact EQ Fund Solutions LLC with any questions toll-free at (888) 540-8736 between 9:00 a.m. and 10:00 p.m. Eastern Time, Monday through Friday, or 10:00 a.m. to 6:00 p.m. Eastern Time on Saturday.