# EDGAR Filing Document

**Accession Number:** 0000063067
**File Stem:** 0000912938-23-000267
**Filing Date:** 2023-3
**Character Count:** 30913
**Document Hash:** 2cc1129111b2249db43b7e3c8c3e0a51
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000912938-23-000267.hdr.sgml**: 20230302

**ACCESSION NUMBER**: 0000912938-23-000267

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 3

**FILED AS OF DATE**: 20230302

**DATE AS OF CHANGE**: 20230302

**EFFECTIVENESS DATE**: 20230302

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MFS SERIES TRUST XVI
- **CENTRAL INDEX KEY:** 0000063067
- **IRS NUMBER:** 000000000
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 497K
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 002-36431
- **FILM NUMBER:** 23696575

**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 GROWTH OPPORTUNITIES FUND
- **DATE OF NAME CHANGE:** 19940304

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MFS CAPITAL DEVELOPMENT FUND
- **DATE OF NAME CHANGE:** 19930408

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MASSACHUSETT MFS CAPITAL DEVELOPMENT FUND
- **DATE OF NAME CHANGE:** 19921015

## Series and Classes Contracts Data

### MFS Prudent Investor Fund (Series ID: S000059884)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000195901 | A            | FPPAX           |
| C000195903 | B            | FPPDX           |
| C000195904 | C            | FPPEX           |
| C000195905 | I            | FPPJX           |
| C000195906 | R1           | FPPRX           |
| C000195907 | R2           | FPPSX           |
| C000195908 | R3           | FPPQX           |
| C000195909 | R4           | FPPUX           |
| C000195910 | R6           | FPPVX           |

![](image0.jpg)

SUMMARY PROSPECTUS

*October 24, 2022 (As Amended December 8, 2022, and March 2, 2023)* 

## MFS<sup>®</sup> Prudent Investor Fund
**** 

<br> **Before you invest**, you may want to review the fund's prospectus, which contains more information about the fund and its risks. You can find the fund's prospectus and other information about the fund, including the fund's reports to shareholders and statement of additional information, online at funds.mfs.com. You can also get this information at no cost by calling 1-800-225-2606 or by sending an e-mail request to orderliterature@mfs.com. The fund's prospectus and statement of additional information, both dated October 24, 2022, as may be amended or supplemented from time to time, are incorporated by reference into this summary prospectus.

---

| | |
|:---|:---|
| &nbsp;&nbsp; **CLASS**  | &nbsp;&nbsp;&nbsp; **TICKER SYMBOL**  |
| &nbsp;&nbsp; **Class A** | &nbsp;&nbsp;&nbsp; FPPAX |
| &nbsp;&nbsp; **Class B** | &nbsp;&nbsp;&nbsp; FPPDX |
| &nbsp;&nbsp; **Class C** | &nbsp;&nbsp;&nbsp; FPPEX |
| &nbsp;&nbsp; **Class I** | &nbsp;&nbsp;&nbsp; FPPJX |
| &nbsp;&nbsp; **Class R1** | &nbsp;&nbsp;&nbsp; FPPRX |
| &nbsp;&nbsp; **Class R2** | &nbsp;&nbsp;&nbsp; FPPSX |
| &nbsp;&nbsp; **Class R3** | &nbsp;&nbsp;&nbsp; FPPQX |
| &nbsp;&nbsp; **Class R4** | &nbsp;&nbsp;&nbsp; FPPUX |
| &nbsp;&nbsp; **Class R6** | &nbsp;&nbsp;&nbsp; FPPVX |

---

#### Summary of Key Information

**#### Investment Objective
The fund's investment objective is to seek capital appreciation.

#### Fees and Expenses
This table describes the fees and expenses that you may pay when you buy, hold, and sell shares of the fund. Investors may also pay commissions or other fees to their financial intermediaries when they buy, hold, and sell shares of the fund, which are not reflected below.

You may qualify for sales charge reductions if, with respect to Class A shares, you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS funds. More information about these and other waivers and reductions is available from your financial intermediary and in "Sales Charges and Waivers and Reductions" on page 13 and "Appendix A – Waivers and Reductions of Sales Charges" on page A-1 of the fund's prospectus.

---

| | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| Shareholder Fees (fees paid directly from your investment): | Shareholder Fees (fees paid directly from your investment): | Shareholder Fees (fees paid directly from your investment): | Shareholder Fees (fees paid directly from your investment): | Shareholder Fees (fees paid directly from your investment): | Shareholder Fees (fees paid directly from your investment): | Shareholder Fees (fees paid directly from your investment): | Shareholder Fees (fees paid directly from your investment): | Shareholder Fees (fees paid directly from your investment): | Shareholder Fees (fees paid directly from your investment): |
| Share Class | A | B | C | I | R1 | R2 | R3 | R4 | R6 |
| Maximum Sales Charge (Load)<br> Imposed on Purchases (as a percentage of offering price) | 5.75% |  |  |  |  |  |  |  |  |
| Maximum Deferred Sales Charge (Load)<br> (as a percentage of original purchase price or redemption proceeds, whichever is less) | 1.00%<sup>#</sup> | 4.00% | 1.00% |  |  |  |  |  |  |

---

---

| | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): | Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): | Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): | Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): | Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): | Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): | Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): | Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): | Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): | Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): |
| Share Class | A | B | C | I | R1 | R2 | R3 | R4 | R6 |
| Management Fee | 0.80% | 0.80% | 0.80% | 0.80% | 0.80% | 0.80% | 0.80% | 0.80% | 0.80% |
| Distribution and/or Service (12b-1) Fees | 0.25% | 1.00% | 1.00% |  | 1.00% | 0.50% | 0.25% |  |  |
| Other Expenses | <u>0.63%</u> | <u>0.63%</u> | <u>0.63%</u> | <u>0.63%</u> | <u>0.63%</u> | <u>0.63%</u> | <u>0.63%</u> | <u>0.63%</u> | <u>0.56%</u> |
| Total Annual Fund Operating Expenses | 1.68% | 2.43% | 2.43% | 1.43% | 2.43% | 1.93% | 1.68% | 1.43% | 1.36% |
| Fee Reductions and/or Expense Reimbursements<sup>1</sup> | <u>(0.44)%</u> | <u>(0.44)%</u> | <u>(0.44)%</u> | <u>(0.44)%</u> | <u>(0.44)%</u> | <u>(0.44)%</u> | <u>(0.44)%</u> | <u>(0.44)%</u> | <u>(0.41)%</u> |
| Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements | 1.24% | 1.99% | 1.99% | 0.99% | 1.99% | 1.49% | 1.24% | 0.99% | 0.95% |

---

# This contingent deferred sales charge (CDSC) applies to shares purchased without an initial sales charge and redeemed within 18 months of purchase.

---

| | |
|:---|:---|
| 1 | Massachusetts Financial Services Company (MFS) has agreed in writing to waive at least 0.01% of the fund's management fee as part of an agreement pursuant to which MFS has agreed to reduce its management fee by a specified amount if certain MFS mutual fund assets exceed thresholds agreed to by MFS and the fund's Board of Trustees. The agreement to waive at least 0.01% of the management fee will continue until modified by the fund's Board of Trustees, but such agreement will continue until at least October 31, 2023. MFS has agreed in writing to bear the fund's expenses, excluding interest, taxes, extraordinary expenses, brokerage and transaction costs, certain tax reclaim recovery expenses (including contingency fees and closing agreement expenses), and investment-related expenses (such as interest and borrowing expenses incurred in connection with the fund's investment activity), such that "Total Annual Fund Operating Expenses" do not exceed 1.24% of the class' average daily net assets annually for each of Class A and Class R3 shares, 1.99% of the class' average daily net assets annually for each of Class B, Class C, and Class R1 shares, 0.99% of the class' average daily net assets annually for each of Class I and Class R4 shares, 1.49% of the class' average daily net assets annually for Class R2 shares, and 0.95% of the class' average daily net assets annually for Class R6 shares. This written agreement will continue until modified by the fund's Board of Trustees, but such agreement will continue until at least October 31, 2023. |

---

FPP-SUM-030223 &nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp; Page 1 of 5<br>

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#### Example
This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds.

The example assumes that: you invest $10,000 in the fund for the time periods indicated and you redeem your shares at the end of the time periods (unless otherwise indicated); your investment has a 5% return each year; and the fund's operating expenses remain the same.

Although your actual costs will likely be higher or lower, under these assumptions your costs would be:

---

| | | | | |
|:---|:---|:---|:---|:---|
|  | 1 YEAR | 3 YEARS | 5 YEARS | 10 YEARS |
| Class A Shares | $694 | $1034 | $1396 | $2413 |
| Class B Shares assuming<sup>1</sup> |  |  |  |  |
| &nbsp;&nbsp;&nbsp; redemption at end of period | $602 | $1016 | $1456 | $2547 |
| &nbsp;&nbsp;&nbsp; no redemption at end of period | $202 | $716 | $1256 | $2547 |
| Class C Shares assuming<sup>1</sup> |  |  |  |  |
| &nbsp;&nbsp;&nbsp; redemption at end of period | $302 | $716 | $1256 | $2547 |
| &nbsp;&nbsp;&nbsp; no redemption at end of period | $202 | $716 | $1256 | $2547 |
| Class I Shares | $101 | $409 | $740 | $1675 |
| Class R1 Shares | $202 | $716 | $1256 | $2733 |
| Class R2 Shares | $152 | $564 | $1001 | $2218 |
| Class R3 Shares | $126 | $487 | $871 | $1950 |
| Class R4 Shares | $101 | $409 | $740 | $1675 |
| Class R6 Shares | $97 | $390 | $706 | $1599 |

---

1 Shares automatically convert to Class A shares approximately eight years after purchase; therefore, the expense examples reflect Class A share expenses after eight years.

#### Portfolio Turnover
The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These transaction costs, which are not reflected in "Annual Fund Operating Expenses" or in the "Example," affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 52% of the average value of its portfolio.

#### Principal Investment Strategies
MFS (Massachusetts Financial Services Company, the fund's investment adviser) normally invests the fund's assets across different asset classes, including an allocation to equity securities and an allocation to debt instruments and/or cash and cash equivalents. MFS allocates the fund's assets across these asset classes based on its assessment of individual securities and the risk/return potential of the asset classes. In managing the fund, MFS seeks to reduce the volatility of the fund's returns relative to the global equity markets, as represented by the MSCI World Index, over a full market cycle.

MFS expects the fund's exposure to the following asset classes to normally fall within the following ranges:

---

| | |
|:---|:---|
| Asset Class | Range |
| Equity Securities | 50% - 90% |
| Debt Instruments, Cash, and/or Cash Equivalents | 10% - 50% |

---

While MFS may use derivatives for any investment purpose, to the extent MFS uses derivatives, MFS expects to use derivatives primarily to increase or decrease exposure to these asset classes, as alternatives to direct investments in these asset classes, or to seek to limit the fund's exposure to certain extreme market events. Derivatives include futures, forward contracts, options, and swaps.

The fund's investment in and exposure to the asset classes identified above may vary significantly from time to time and may fall outside of the stated ranges. MFS may invest in or expose the fund to any of these asset classes without limit based on its assessment of the relative attractiveness of the asset class.

Equity securities include common stocks and other securities that represent an ownership interest (or right to acquire an ownership interest) in a company or other issuer. In selecting equity investments for the fund, MFS is not constrained by any particular investment style. MFS may invest the fund's assets in the stocks of companies it believes to have above average earnings growth potential compared to other companies (growth companies), in the stocks of companies it believes are undervalued compared to their perceived worth (value companies), or in a combination of growth and value companies. While MFS may invest the equity portion of the fund's assets in securities of companies of any size, MFS primarily invests in securities of companies with large capitalizations.

Debt instruments include corporate bonds, U.S. Government securities, foreign government securities, securitized instruments (including mortgage-backed securities and other asset-backed securities), floating rate loans, and other obligations to repay money borrowed. Of the fund's investments in debt instruments, MFS may invest up to 100% of these investments in below investment grade quality debt instruments.

MFS may at times invest a significant percentage of the fund's assets in short-term government securities, cash and/or cash equivalents. Cash equivalents include money market instruments and a money market fund advised by MFS.

MFS invests the fund's assets in U.S. and foreign securities, including emerging market securities.

MFS normally invests the fund's assets across different industries, sectors, countries, and regions, but MFS may invest a significant percentage of the fund's assets in issuers in a single industry, sector, country, or region.

MFS may invest a significant percentage of the fund's assets in a single issuer or a small number of issuers.

MFS uses an active bottom-up investment approach to buying and selling investments for the fund. Investments are selected primarily based on fundamental analysis of individual issuers and instruments. Quantitative screening tools that systematically evaluate issuers and instruments may also be considered.

In light of the fund's principal investment strategies described above, MFS believes it is reasonable to measure the fund's performance (net of fund expenses) over a full market cycle relative to the performance of (i) the MSCI World Index and (ii) the ICE

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BofA 0-3 Month U.S. Treasury Bill Index plus 3% to 5%. MFS does not seek to achieve a specific rate of return in managing the fund and there is no assurance that the fund will outperform the MSCI World Index or the ICE BofA 0-3 Month U.S. Treasury Bill Index over the long term or for any year or period of years.

The term "prudent investor" can suggest different meanings to different investors and the use of the term "prudent investor" in the fund's name is not meant to suggest the fund will follow a specific investment strategy other than the principal investment strategies disclosed above.

#### Principal Risks
As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund. An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

The principal risks of investing in the fund are:

Allocation Risk: MFS' assessment of the risk/return potential of asset classes and the resulting allocation among asset classes may not produce the intended results and/or can lead to an investment focus that results in the fund underperforming other funds with similar investment strategies and/or underperforming the markets in which the fund invests. It is expected that the fund will generally underperform the equity markets during periods of strong, rising equity markets.

Investment Selection Risk: MFS' investment analysis and its selection of investments may not produce the intended results and/or can lead to an investment focus that results in the fund underperforming other funds with similar investment strategies and/or underperforming the markets in which the fund invests. There is no assurance that the fund will achieve a positive rate of return or have lower volatility than the global equity markets, as represented by the MSCI World Index, over the long term or for any year or period of years. In addition, the strategies MFS may implement to limit the fund's exposure to certain extreme market events may not work as intended, and the costs associated with such strategies will reduce the fund's returns. It is expected that the fund will generally underperform the equity markets during periods of strong, rising equity markets.

Equity Market Risk/Company Risk: Equity markets are volatile and can decline significantly in response to changes in, or investor perceptions of, issuer, market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions. These conditions can affect a single issuer or type of security, issuers within a broad market sector, industry or geographic region, or the equity markets in general. Certain events can have a dramatic adverse effect on equity markets and may lead to periods of high volatility in an equity market or a segment of an equity market. The value of an investment held by the fund may decline due to factors directly related to the issuer.

Debt Market Risk: Debt markets can be volatile and can decline significantly in response to changes in, or investor perceptions of, issuer, market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions. These conditions can affect a single instrument, issuer, or borrower, a particular type of instrument, issuer, or borrower, a segment of the debt markets or the debt markets generally. Certain events can have a dramatic adverse effect on debt markets and may lead to periods of high volatility and reduced liquidity in a debt market or segment of a debt market.

Interest Rate Risk: In general, the price of a debt instrument falls when interest rates rise and rises when interest rates fall. Interest rate risk is generally greater for instruments with longer maturities, or that do not pay current interest.

Credit Risk: The price of a debt instrument depends, in part, on the credit quality of the issuer, borrower, counterparty, or other entity responsible for payment, or underlying collateral or assets and the terms of the instrument. The price of a debt instrument can decline in response to changes in, or perceptions of, the financial condition of the issuer, borrower, counterparty, or other entity, or underlying collateral or assets, or changes in, or perceptions of, specific or general market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions.

Below investment grade quality debt instruments (commonly referred to as "high yield securities" or "junk bonds") can involve a substantially greater risk of default or can already be in default, and their values can decline significantly. Below investment grade quality debt instruments are regarded as having predominantly speculative characteristics. Below investment grade quality debt instruments tend to be more sensitive to adverse news about the issuer, or the market or economy in general, than higher quality debt instruments.

Foreign Risk: Exposure to foreign markets through issuers or currencies can involve additional risks relating to market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions. These factors can make foreign investments, especially those tied economically to emerging markets or countries subject to sanctions or the threat of new or modified sanctions, more volatile and less liquid than U.S. investments. In addition, foreign markets can react differently to these conditions than the U.S. market.

Emerging Markets Risk: Investments tied economically to emerging markets, especially frontier markets, can involve additional and greater risks than the risks associated with investments in developed markets. Emerging markets can have less developed markets, greater custody and operational risk, less developed legal, regulatory, and accounting systems, greater government involvement in the economy, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater political, social, geopolitical, and economic instability than developed markets.

Currency Risk: The value of foreign currencies relative to the U.S. dollar fluctuates in response to market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions, and changes in currency exchange rates impact the financial condition of companies or other issuers and may change the value in U.S. dollars of investments denominated in foreign currencies.

Focus Risk: Issuers in a single industry, sector, country, or region can react similarly to market, currency, political, economic, regulatory, geopolitical, environmental, public health, and other conditions, and the fund's performance will be affected by the conditions in the industries, sectors, countries and regions to which the fund is exposed. If MFS invests a significant percentage of the fund's assets in a single issuer or small number of issuers, the fund's performance could be more volatile than the performance of more diversified funds.

Prepayment/Extension Risk: Instruments subject to prepayment and/or extension can reduce the potential for gain for the instrument's holders if the instrument is prepaid and increase the potential for loss if the maturity of the instrument is extended.

Derivatives Risk: Derivatives can be highly volatile and involve risks in addition to the risks of the underlying indicator(s) on which the derivative is based. Gains or losses from derivatives can be

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substantially greater than the derivatives' original cost. Derivatives can involve leverage.

Leveraging Risk: Leverage involves investment exposure in an amount exceeding the initial investment. Leverage can cause increased volatility by magnifying gains or losses.

Counterparty and Third Party Risk: Transactions involving a counterparty or third party other than the issuer of the instrument are subject to the credit risk of the counterparty or third party, and to the counterparty's or third party's ability or willingness to perform in accordance with the terms of the transaction.

Liquidity Risk: It may be difficult to value, and it may not be possible to sell, certain investments, types of investments, and/or investments in certain segments of the market, and the fund may have to sell certain of these investments at prices or times that are not advantageous in order to meet redemptions or other cash needs.

Large Shareholder Risk: From time to time, shareholders of the fund (which may include institutional investors, financial intermediaries, or other MFS funds) may make relatively large redemptions or purchases of fund shares. These transactions may cause the fund to sell securities or invest additional cash, as the case may be, at disadvantageous prices. Redemptions of a large number of shares also may increase transaction and other costs or have adverse tax consequences for shareholders of the fund by requiring a sale of portfolio securities. Purchases of a large number of shares may adversely affect the fund's performance to the extent that it takes time to invest new cash and the fund maintains a larger cash position than it ordinarily would.

#### Performance Information
The bar chart and performance table below are intended to provide some indication of the risks of investing in the fund by showing how the fund's performance over time compares with that of a broad measure of market performance and one or more measures of performance for markets in which the fund may invest.

The fund's past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future. Updated performance is available online at mfs.com or by calling 1-800-225-2606.

Class A Bar Chart. The bar chart does not take into account any sales charges (loads) that you may be required to pay upon purchase or redemption of the fund's shares. If these sales charges were included, they would reduce the returns shown.<br>

![](image00001.jpg)

The total return for the nine-month period ended September 30, 2022, was (18.86)%. During the period(s) shown in the bar chart, the highest quarterly return was 7.23% (for the calendar quarter ended March 31, 2019) and the lowest quarterly return was (2.09)% (for the calendar quarter ended March 31, 2021).

Performance Table.

---

| |
|:---|
| Average Annual Total Returns |
| (For the Periods Ended December 31, 2021) |

---

---

| | | |
|:---|:---|:---|
| Share Class | 1 YEAR | LIFE<br> (INCEPTION 1-18-2018) |
| Returns Before Taxes | Returns Before Taxes | Returns Before Taxes |
| B Shares | (3.15)% | 4.55% |
| C Shares | (0.25)% | 5.21% |
| I Shares | 1.89% | 6.26% |
| R1 Shares | 0.73% | 5.19% |
| R2 Shares | 1.29% | 5.73% |
| R3 Shares | 1.54% | 5.99% |
| R4 Shares | 1.80% | 6.25% |
| R6 Shares | 1.95% | 6.31% |
| A Shares | (4.29)% | 4.42% |
| Returns After Taxes on Distributions |  |  |
| A Shares | (4.75)% | 3.99% |
| Returns After Taxes on Distributions and Sale of Fund Shares |  |  |
| A Shares | (2.22)% | 3.32% |
| Index Comparisons (Reflects no deduction for fees, expenses, or taxes) |  |  |
| MSCI World Index (net div) | 21.82% | 12.13% |
| ICE BofA 0-3 Month U.S. Treasury Bill Index | 0.05% | 1.16% |

---

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your own tax situation, and may differ from those shown. The after-tax returns shown are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. The after-tax returns are shown for only one of the fund's classes of shares, and after-tax returns for the fund's other classes of shares will vary from the returns shown.

#### Investment Adviser
MFS serves as the investment adviser for the fund.

#### Portfolio Manager(s)

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Portfolio Manager | &nbsp;&nbsp;&nbsp; Since | &nbsp;&nbsp;&nbsp; Title |
| &nbsp;&nbsp; David Cole | &nbsp;&nbsp;&nbsp; 2018 | &nbsp;&nbsp;&nbsp; Investment Officer of MFS |
| &nbsp;&nbsp; Shanti Das-Wermes | &nbsp;&nbsp;&nbsp; January 2022 | &nbsp;&nbsp;&nbsp; Investment Officer of MFS |
| &nbsp;&nbsp; Edward Dearing | &nbsp;&nbsp;&nbsp; 2018 | &nbsp;&nbsp;&nbsp; Investment Officer of MFS |
| &nbsp;&nbsp; Barnaby Wiener | &nbsp;&nbsp;&nbsp; 2018 | &nbsp;&nbsp;&nbsp; Investment Officer and Chief Sustainability Officer of MFS |

---

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

#### Purchase and Sale of Fund Shares
You may purchase and redeem shares of the fund each day the New York Stock Exchange (the NYSE) is open for trading. You may

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purchase or redeem shares either by having your financial intermediary process your purchase or redemption, or through MFS Service Center, Inc. (MFSC) by overnight mail (MFSC, Suite 219341, 430 W 7<sup>th</sup> Street, Kansas City, MO 64105-1407), by mail ([Fund Name], P.O. Box 219341, Kansas City, MO 64121-9341), by telephone (1-800-225-2606), or via the Internet at mfs.com (MFS Access).

The fund's initial and subsequent investment minimums generally are as follows:

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| | | |
|:---|:---|:---|
| &nbsp;&nbsp; Class | &nbsp;&nbsp;&nbsp; Initial Minimum | &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;Subsequent Minimum |
| &nbsp;&nbsp; Class A, Class B, Class C | &nbsp;&nbsp;&nbsp;&nbsp; None – automatic investment plans and certain asset-based fee programs<br> $25 – employer-sponsored retirement plans<br> $250 – Traditional and Roth IRAs<br> $1,000 – other accounts | &nbsp;&nbsp;&nbsp;&nbsp; $50 – by check and non-systematic written exchange request, and via MFSC telephone representatives<br> None – other purchases |
| &nbsp;&nbsp; Class I, Class R1, Class R2, Class R3, Class R4, Class R6 |  |  |

---

Purchases of Class B shares are closed to new and existing investors except through reinvestment of dividends and capital gain distributions. Existing investors may continue to exchange their Class B shares for the same share class of another MFS fund.

#### Taxes
If your shares are held in a taxable account, the fund's distributions will be taxed to you as ordinary income and/or capital gains. If your shares are held in a tax-advantaged account, you will generally be taxed only upon withdrawals from the account.

#### Payments to Broker/Dealers and Other Financial Intermediaries
If you purchase shares of the fund through a broker/dealer or other financial intermediary (such as a bank), the fund, MFS, and/or MFS' affiliates may pay the financial intermediary for the sale of shares of the fund and/or the servicing of shareholder accounts. These payments may create a conflict of interest by influencing your broker/dealer or other financial intermediary and your salesperson to recommend the fund over another investment. Ask your financial intermediary or visit your financial intermediary's website for more information.

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#### <br>**

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