# MFS Investment Management

> MFS Investment Management is an SEC-registered investment advisory firm in Boston, MA, registered since 1982, reporting over $5 billion in regulatory assets under management in its Form ADV filing dated March 31, 2026.

- CRD: 110045
- Filed as: MFS INVESTMENT MANAGEMENT
- Legal name: Massachusetts Financial Services Company
- Also doing business as: MASSACHUSETTS FINANCIAL SERVICES COMPANY
- Registration: SEC-registered investment adviser (status as filed: Approved)
- Location: Boston, MA
- Filing period: October 2026
- Form ADV filing dated: March 31, 2026
- SEC record (IAPD): https://adviserinfo.sec.gov/firm/summary/110045
- AdvisorCensus page: https://advisorcensus.com/firm/mfs-investment-management-boston-ma-110045

## Quick answers

**How is MFS Investment Management compensated?**
On its Form ADV (Item 5.E, October 2026), MFS Investment Management reports these compensation arrangements: a percentage of assets under its management; other.

**Where is MFS Investment Management located?**
MFS Investment Management's principal office is in Boston, MA, according to its Form ADV.

**Is MFS Investment Management registered with the SEC or a state?**
MFS Investment Management is an SEC-registered investment advisory firm, registered since 1982. Status as filed: Approved. CRD 110045.

**How much does MFS Investment Management manage?**
MFS Investment Management reports $514,051,177,297 in regulatory assets under management in its Form ADV filing dated March 31, 2026 (93% discretionary).

**How have MFS Investment Management's assets and staff changed since 2021?**
In the Form ADV data for MFS Investment Management: Regulatory assets under management: $495,512,689,615 in the October 2021 data and $514,051,177,297 in the October 2026 data, up 4%. Total employees: 1,500 in October 2021 and 1,244 in October 2026. Assets under management move with markets as well as with clients coming and going.

**What types of clients does MFS Investment Management serve?**
By number of clients on Form ADV Item 5.D: investment companies (187); pooled investment vehicles (other than investment companies and business development companies) (115); corporations or other businesses not listed above (26).

**Which custodians does MFS Investment Management use?**
MFS Investment Management's most recent Form ADV filing (Schedule D, Section 5.K(3)) lists Brown Brothers Harriman & Co., JP Morgan Chase Bank, N.A. London, State Street Bank and Trust Co., Sumitomo Mitsui Trust Bank (U.S.A.) Limited and The Northern Trust Company as custodians holding 10% or more of its separately managed account assets.

**Does MFS Investment Management report any disciplinary disclosures?**
Reports 4 disclosure items on Form ADV Item 11: yes answers to 11.C(1) (SEC or CFTC finding of a false statement or omission), 11.C(2) (SEC or CFTC finding of a violation), 11.C(4) (SEC or CFTC order), and 11.C(5) (SEC or CFTC civil money penalty or cease-and-desist order). Each question covers the firm and its advisory affiliates, and one event can produce several yes answers. The detail of any item is on the firm's SEC record: https://adviserinfo.sec.gov/firm/summary/110045

**What changed in MFS Investment Management's recent Form ADV filings?**
In the April 2026 filing data: Employees performing advisory functions went from 331 to 327. Updated its list of owners and control persons (Schedule A).

## From the Form ADV filing

### Compensation (Item 5.E)
- A percentage of assets under your management
- Other

### Custodians (Schedule D, Section 5.K(3))
- Brown Brothers Harriman & Co.
- JP Morgan Chase Bank, N.A. London
- State Street Bank and Trust Co.
- Sumitomo Mitsui Trust Bank (U.S.A.) Limited
- The Northern Trust Company

Custodians holding 10% or more of the firm's separately managed account assets, as filed on Form ADV (Schedule D, Section 5.K(3)). A custodian holds client assets; it does not endorse or supervise the firm. AdvisorCensus has no relationship with any custodian.

### Regulatory assets under management (Item 5.F)
- Total: $514,051,177,297
- Discretionary: $476,823,104,264
- Non-discretionary: $37,228,073,033

### Clients (Item 5.D)

| Client type | Clients | Assets |
| --- | --- | --- |
| Individuals (other than high net worth individuals) | 0 | $0 |
| High net worth individuals | 0 | $0 |
| Banking or thrift institutions | 0 | $0 |
| Investment companies | 187 | $436,503,794,913 |
| Business development companies | 0 | $0 |
| Pooled investment vehicles (other than investment companies and business development companies) | 115 | $70,809,843,695 |
| Pension and profit sharing plans (but not the plan participants or government pension plans) | 18 | $3,294,871,647 |
| Charitable organizations | 1 | $51,059,768 |
| State or municipal government entities (including government pension plans) | 2 | $704,813,501 |
| Other investment advisers | 0 | $0 |
| Insurance companies | 2 | $86,544,072 |
| Sovereign wealth funds and foreign official institutions | 4 | $2,457,542,471 |
| Corporations or other businesses not listed above | 26 | $142,707,230 |
| Other | 0 | $0 |

### Advisory services (Item 5.G)
- Portfolio management for investment companies (and business development companies)
- Portfolio management for pooled investment vehicles (other than investment companies)
- Portfolio management for businesses (other than small businesses) or institutional clients

### Firm details
- Registered since: 1982 (44 years)
- Employees: 1,244 total, 327 performing advisory functions
- Wrap fee program participation: No
- Disclosures (Item 11): Reports 4 disclosure items on Form ADV Item 11.

### Item 11 questions answered yes
- 11.C(1): Has the SEC or the CFTC ever found that the firm or an advisory affiliate made a false statement or omission?
- 11.C(2): Has the SEC or the CFTC ever found that the firm or an advisory affiliate was involved in a violation of SEC or CFTC regulations or statutes?
- 11.C(4): Has the SEC or the CFTC ever entered an order against the firm or an advisory affiliate in connection with investment-related activity?
- 11.C(5): Has the SEC or the CFTC ever imposed a civil money penalty on the firm or an advisory affiliate, or ordered the firm or an advisory affiliate to cease and desist from an activity?

Each question covers the firm and its advisory affiliates: its current employees other than clerical staff, its officers, partners, and directors, and anyone who controls the firm or is controlled by it. One event can produce yes answers to several questions. SEC-registered advisers and exempt reporting advisers may leave out events more than ten years old, and may answer 11.A(2) and 11.B(2) for pending charges only. The detail of each yes answer is on the firm's SEC record: https://adviserinfo.sec.gov/firm/summary/110045

### Websites listed on Form ADV (Item 1.I)
- mfs.com
- xing.com/pages/mfs-investment-management
- Facebook @followmfs
- LinkedIn @mfs-investment-management
- X @followmfs
- YouTube @followmfs

## Assets and staff over time

| Data period | Regulatory assets under management | Employees | Filing dated |
| --- | --- | --- | --- |
| October 2021 | $495,512,689,615 | 1,500 | July 15, 2021 |
| October 2022 | $556,803,162,123 | 1,100 | May 26, 2022 |
| October 2023 | $417,408,071,971 | 1,200 | September 6, 2023 |
| October 2024 | $454,325,314,664 | 1,300 | July 25, 2024 |
| October 2025 | $473,025,951,992 | 1,271 | March 31, 2025 |
| October 2026 | $514,051,177,297 | 1,244 | March 31, 2026 |

Regulatory assets under management: $495,512,689,615 in the October 2021 data and $514,051,177,297 in the October 2026 data, up 4%.
Total employees: 1,500 in October 2021 and 1,244 in October 2026.

## Changes in the filing (last 12 months)

### April 2026
- Employees performing advisory functions went from 331 to 327.
- Updated its list of owners and control persons (Schedule A).

### February 2026
- Updated its list of owners and control persons (Schedule A).

### December 2025
- Item 11 disclosure answers changed: 4 yes answers, previously 7 (now no: 11.D(2), 11.D(4), 11.E(2)).

### November 2025
- Updated its list of owners and control persons (Schedule A).

## Source

Form ADV as filed, October 2026. Values appear as filed. Cite as: AdvisorCensus. MFS Investment Management (CRD 110045): Form ADV filing data as of October 2026.