# EDGAR Filing Document

**Accession Number:** 0000783740
**File Stem:** 0000912938-23-000231
**Filing Date:** 2023-2
**Character Count:** 4709
**Document Hash:** 39d416d1ec86f173d23c12227ff7be31
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000912938-23-000231.hdr.sgml**: 20230209

**ACCESSION NUMBER**: 0000912938-23-000231

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20230209

**DATE AS OF CHANGE**: 20230209

**EFFECTIVENESS DATE**: 20230209

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MFS SERIES TRUST X
- **CENTRAL INDEX KEY:** 0000783740
- **IRS NUMBER:** 000000000
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 1130

**FILING VALUES:**
- **FORM TYPE:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-01657
- **FILM NUMBER:** 23601378

**BUSINESS ADDRESS:**
- **STREET 1:** 111 HUNTINGTON AVENUE
- **STREET 2:** 21ST FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02199
- **BUSINESS PHONE:** 18006372929

**MAIL ADDRESS:**
- **STREET 1:** 111 HUNTINGTON AVENUE
- **STREET 2:** 21ST FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02199

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MFS GOVERNMENT MORTGAGE FUND
- **DATE OF NAME CHANGE:** 19930408

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MFS GOVERNMENT INCOME PLUS FUND
- **DATE OF NAME CHANGE:** 19930312

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MASSACHUSETTS MFS GOVERNMENT INCOME PLUS FUND
- **DATE OF NAME CHANGE:** 19921015

## Series and Classes Contracts Data

### MFS Global Opportunistic Bond Fund (Series ID: S000028956)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| A          | MGBAX         | C000088935 |
| B          | MGBBX         | C000088936 |
| C          | MGBDX         | C000088937 |
| I          | MGBJX         | C000088938 |
| R1         | MGBKX         | C000088939 |
| R2         | MGBLX         | C000088940 |
| R3         | MGBMX         | C000088941 |
| R4         | MGBNX         | C000088942 |
| R6         | MGBOX         | C000120923 |

---

## Series and Classes Contracts Data

### MFS Global Opportunistic Bond Fund (Series ID: S000028956)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000088935 | A            | MGBAX           |
| C000088936 | B            | MGBBX           |
| C000088937 | C            | MGBDX           |
| C000088938 | I            | MGBJX           |
| C000088939 | R1           | MGBKX           |
| C000088940 | R2           | MGBLX           |
| C000088941 | R3           | MGBMX           |
| C000088942 | R4           | MGBNX           |
| C000120923 | R6           | MGBOX           |

![](image0.jpg)

SUPPLEMENT TO THE PROSPECTUS

*Supplement dated February 9, 2023, to the Prospectus dated March 30, 2022.*

## MFS<sup>®</sup> Global Opportunistic Bond Fund
(formerly MFS<sup>®</sup> Global Bond Fund)

------

**Effective March 31, 2023, the following is added to the table in the section entitled "Portfolio Manager(s)" under the main heading entitled "Summary of Key Information":**

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; **Portfolio Manager** | &nbsp;&nbsp;&nbsp; **Since** | &nbsp;&nbsp;&nbsp; **Title** |
| &nbsp;&nbsp; Neeraj Arora | &nbsp;&nbsp;&nbsp; March 2023 | &nbsp;&nbsp;&nbsp; Investment Officer of MFS |

---

**Effective immediately, the following is added after the tables in the sections entitled "Portfolio Manager(s)" under the main headings entitled "Summary of Key Information" and "Management of the Fund":**

Effective April 30, 2024, Matt Ryan will no longer be a portfolio manager of the fund.

**Effective March 31, 2023, the following is added to the table in the section entitled "Portfolio Manager(s)" under the main heading entitled "Management of the Fund":**

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; **Portfolio Manager** | &nbsp;&nbsp;&nbsp; **Primary Role** | &nbsp;&nbsp;&nbsp; **Five Year History** |
| &nbsp;&nbsp; Neeraj Arora | &nbsp;&nbsp; Emerging Markets Debt Instruments Portfolio Manager | &nbsp;&nbsp; Employed in the investment area of MFS since 2011 |

---

1050251 1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; GLB-SUP-I-020923

<br>