# EDGAR Filing Document

**Accession Number:** 0001380192
**File Stem:** 0000276776-23-000041
**Filing Date:** 2023-3
**Character Count:** 316229
**Document Hash:** 70921edbd1d05b24eef44db3fbcd381b
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000276776-23-000041.hdr.sgml**: 20230303

**ACCESSION NUMBER**: 0000276776-23-000041

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 4

**FILED AS OF DATE**: 20230303

**DATE AS OF CHANGE**: 20230303

**EFFECTIVENESS DATE**: 20230303

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Pioneer Series Trust VI
- **CENTRAL INDEX KEY:** 0001380192
- **IRS NUMBER:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1031

**FILING VALUES:**
- **FORM TYPE:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-138560
- **FILM NUMBER:** 23702533

**BUSINESS ADDRESS:**
- **STREET 1:** 60 STATE STREET
- **STREET 2:** 5TH FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02109
- **BUSINESS PHONE:** 617-742-7825

**MAIL ADDRESS:**
- **STREET 1:** 60 STATE STREET
- **STREET 2:** 5TH FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02109

## Series and Classes Contracts Data

### Pioneer Floating Rate Fund (Series ID: S000015510)

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|  |  |  |
|:---|:---|:---|
| Class Name                          | Ticker Symbol | Class ID   |
| Pioneer Floating Rate Fund: Class A | FLARX         | C000042204 |
| Pioneer Floating Rate Fund: Class C | FLRCX         | C000042205 |
| Pioneer Floating Rate Fund: Class Y | FLYRX         | C000042206 |
| Pioneer Floating Rate Fund: Class K | FLRKX         | C000135272 |

---

## Series and Classes Contracts Data

### Pioneer Floating Rate Fund (Series ID: S000015510)

| Class ID   | Class Name                          | Ticker Symbol   |
|:---|:---|:---|
| C000042204 | Pioneer Floating Rate Fund: Class A | FLARX           |
| C000042205 | Pioneer Floating Rate Fund: Class C | FLRCX           |
| C000042206 | Pioneer Floating Rate Fund: Class Y | FLYRX           |
| C000135272 | Pioneer Floating Rate Fund: Class K | FLRKX           |

**Pioneer Floating Rate Fund** 

Prospectus \| March 1, 2023

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| | | | |
|:---|:---|:---|:---|
| **Class A Shares** | **Class C Shares** | **Class K Shares** | **Class Y Shares** |
| **FLARX** | **FLRCX** | **FLRKX** | **FLYRX** |

---

**Contents** 

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| | |
|:---|:---|
| [Fund summary](#xx_b115c1f5-0a9a-4a56-85fb-cfc4229ef6a7_1) | 1  |
| [More on the fund's investment objective and strategies](#xx_5b11bc54-695c-43c6-9db0-64588d47a1aa_1) | 23  |
| [More on the risks of investing in the fund](#xx_3e4642a5-11be-41dd-bb1a-936745720e60_1) | 35  |
| [Management](#xx_3e4642a5-11be-41dd-bb1a-936745720e60_30) | 64  |
| [Pricing of shares](#xx_3e4642a5-11be-41dd-bb1a-936745720e60_32) | 66  |
| [Choosing a class of shares](#xx_3e4642a5-11be-41dd-bb1a-936745720e60_34) | 68  |
| [Distribution and service arrangements](#xx_3e4642a5-11be-41dd-bb1a-936745720e60_38) | 72  |
| [Sales charges](#xx_3e4642a5-11be-41dd-bb1a-936745720e60_40) | 74  |
| [Buying, exchanging and selling shares](#xx_3e4642a5-11be-41dd-bb1a-936745720e60_47) | 81  |
| [Account options](#xx_3e4642a5-11be-41dd-bb1a-936745720e60_59) | 93  |
| [Shareholder services and policies](#xx_3e4642a5-11be-41dd-bb1a-936745720e60_63) | 97  |
| [Dividends, capital gains and taxes](#xx_3e4642a5-11be-41dd-bb1a-936745720e60_69) | 103  |
| [Financial highlights](#xx_c434e316-a1b5-4499-ba40-4bb8e01f52af_1) | 105  |
| [Intermediary defined sales charge waiver policies](#xx_7e1db07f-ad5d-4032-aa18-5043510134a3_1) | 109 |

---

Neither the Securities and Exchange Commission nor any state securities agency has approved or disapproved the fund's shares or determined whether this prospectus is accurate or complete. Any representation to the contrary is a crime.

![](covers_amundipioneer2.jpg)

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**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 government agency.**

**Contact your investment professional to discuss how the fund may fit into your portfolio.**

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**Fund summary**

**Investment objective**

A high level of current income.

**Fees and expenses of the fund**

This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the fund. **You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.**

You may qualify for sales charge discounts if you or your family invest, or agree to invest in the future, at least $100,000 in Class A shares of the Pioneer funds. More information about these and other discounts is available from your investment professional and in the "Sales charges" section of the prospectus beginning on page 74, the "Intermediary defined sales charge waiver policies" section of the prospectus beginning on page 109, and the "Sales charges" section of the statement of additional information beginning on page 64. If you invest in Class K shares or Class Y shares through an investment professional or financial intermediary, that investment professional or financial intermediary may charge you a commission. Such commissions, if any, are not charged by the fund and are not reflected in the fee table or expense example below.

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**Fund summary**

**Shareowner fees** <br>(fees paid directly from your investment)

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| | | | | |
|:---|:---|:---|:---|:---|
|  | **Class A** | **Class C** | **Class K** | **Class Y** |
| Maximum sales charge (load) when you buy shares (as a <br> percentage of offering price)<br>| 4.50% |  |  |  |
| Maximum deferred sales charge (load) (as a percentage of <br> offering price or the amount you receive when you sell <br> shares, whichever is less)<br>| None<sup>1</sup> <br>| 1% |  |  |

---

**Annual fund operating expenses** <br>(expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | |
|:---|:---|:---|:---|:---|
|  | **Class A** | **Class C** | **Class K** | **Class Y** |
| Management Fees | 0.60% | 0.60% | 0.60% | 0.60% |
| Distribution and Service (12b-1) Fees | 0.25% | 1.00% | 0.00% | 0.00% |
| Other Expenses<sup>2</sup> <br>| 0.37% | 0.19% | 0.12% | 0.22% |
| Acquired Fund Fees and Expenses<sup>3</sup> <br>| 0.02% | 0.02% | 0.02% | 0.02% |
| Total Annual Fund Operating Expenses Plus Acquired Fund <br> Fees and Expenses<sup>3</sup> <br>| 1.24% | 1.81% | 0.74% | 0.84% |
| Less: Fee Waiver and Expense Reimbursement<sup>4</sup> <br>| -0.17% | 0.00% | 0.00% | -0.07% |
| Net Expenses Plus Acquired Fund Fees and Expenses<sup>4</sup> <br>| 1.07% | 1.81% | 0.74% | 0.77% |

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Class A purchases of $500,000 or more that are not subject to an initial sales charge may be subject to a contingent deferred sales charge of 1%. See "Sales charges."

Other expenses for Class K shares are estimated for the current fiscal year.

Total annual fund operating expenses in the table, before and after fee waivers and expense reimbursements, are higher than the corresponding ratios of expenses to average net assets shown in the "Financial Highlights" section, which do not include acquired fund fees and expenses.

The fund's investment adviser has contractually agreed to limit ordinary operating expenses (ordinary operating expenses means all fund expenses other than taxes, brokerage commissions, acquired fund fees and expenses, and extraordinary expenses, such as litigation) to the extent required to reduce fund expenses to 1.05% and 0.75% of the average daily net assets attributable to Class A and Class Y shares, respectively. These expense limitations are in effect through March 1, 2024. There can be no assurance that the adviser will extend these expense limitation beyond such time. Net expenses for a Class may exceed the applicable expense limitation to the extent that the fund incurs excluded expenses. While in effect, the arrangement may be terminated for a class only by agreement of the adviser and the Board of Trustees.

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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 shown and then, except as indicated, redeem all of your shares at the end of those periods. It also assumes that (a) your investment has a 5% return each year and (b) the fund's total annual operating expenses remain the same except for year one (which considers the effect of the expense limitation). Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | **If you redeem your shares** | **If you redeem your shares** | **If you redeem your shares** | **If you redeem your shares** | **If you do not redeem your shares** | **If you do not redeem your shares** | **If you do not redeem your shares** | **If you do not redeem your shares** |
|  | **Number of years you own your shares** | **Number of years you own your shares** | **Number of years you own your shares** | **Number of years you own your shares** | **Number of years you own your shares** | **Number of years you own your shares** | **Number of years you own your shares** | **Number of years you own your shares** |
|  | **1** | **3** | **5** | **10** | **1** | **3** | **5** | **10** |
| Class A | $554 | $810 | $1085 | $1868 | $554 | $810 | $1085 | $1868 |
| Class C | 284 | 569 | 980 | 2127 | 184 | 569 | 980 | 2127 |
| Class K | 76 | 237 | 411 | 918 | 76 | 237 | 411 | 918 |
| Class Y | 79 | 261 | 459 | 1031 | 79 | 261 | 459 | 1031 |

---

**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 fund shares are held in a taxable account. These 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 45% of the average value of its portfolio.

**Principal investment strategies**

Normally, the fund invests at least 80% of its net assets (plus the amount of borrowings, if any, for investment purposes) in floating rate loans and other floating rate investments. Derivative investments that provide exposure to such floating rate securities or have similar economic characteristics may be used to satisfy the fund's 80% policy. Floating rate investments are securities and other instruments with interest rates that adjust or "float" periodically based on a specified interest rate or other reference and include senior secured floating rate loans, repurchase agreements, money market securities and shares of money market and short term bond funds. The fund also considers as floating rate instruments, and the fund may invest without limit in, adjustable rate securities, fixed rate securities with durations of less than or equal to one year, securities of other investment companies (including mutual funds, exchange-traded funds and closed-end funds) that invest primarily

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**Fund summary**

in floating rate instruments, and fixed rate securities with respect to which the fund has entered into derivative instruments to effectively convert the fixed rate interest payments into floating rate interest payments. The fund considers these investments as economic equivalents of floating rate instruments.

Floating rate loans typically are rated below investment grade (debt securities rated below investment grade are commonly referred to as "junk bonds"). The fund's investments in floating rate loans typically hold a senior position in the borrower's capital structure, but may also include unsecured or subordinated loans.

The fund's investments also may include revolving credit facility loans, high yield corporate bonds (also known as "junk bonds"), investment grade fixed income debt securities, preferred stocks and convertible securities. The fund may receive debt securities or equity securities as a result of the general restructuring of the debt of an issuer, the restructuring of a floating rate loan, or as part of a package of securities acquired with a loan.

The fund may invest up to 35% of its total assets in debt securities of non-U.S. issuers, including emerging market issuers. The fund does not currently intend to invest more than 25% of its total assets in any one non-U.S. country.

The fund may invest without limit in securities of any rating, including those of issuers that are in default. The fund does not have a targeted maturity range for its portfolio. The fund invests in securities of any maturity. The maturity of a fixed income security is a measure of the time remaining until final payment on the security is due. The fund's investments may have fixed or variable principal payments and all types of interest rate and dividend payment and reset terms, including fixed rate, adjustable rate, floating rate, contingent, deferred, payment in kind and auction rate features. The fund has the ability to invest in a broad range of issuers and segments of the debt securities market. The fund may invest in securities of issuers in any market capitalization range, industry or market sector.

The fund may invest in mortgage-related securities, including commercial mortgage-backed securities, collateralized mortgage obligations, credit risk transfer securities and "sub-prime" mortgages and asset-backed securities. The fund's investments in mortgage-related securities may include instruments, the underlying assets of which allow for balloon payments (where a substantial portion of a mortgage loan balance is paid at maturity, which can shorten the average life of the mortgage-backed instrument) or negative amortization payments (where as a result of a payment cap, payments on a mortgage loan are less than the amount of principal and interest owed, with excess amounts added to the outstanding principal balance, which can extend the average life of the mortgage-backed instrument).

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The fund also may invest in U.S. government securities, zero coupon securities, subordinated debt securities and insurance-linked securities.

The fund may, but is not required to, use derivatives, such as credit default swaps, forward foreign currency exchange contracts and bond and interest rate futures. The fund may use derivatives for a variety of purposes, including: in an attempt to hedge against adverse changes in the market price of securities, interest rates or currency exchange rates; as a substitute for purchasing or selling securities; to attempt to increase the fund's return as a non-hedging strategy that may be considered speculative; to manage portfolio characteristics: and as a cash flow management technique. The fund may choose not to make use of derivatives for a variety of reasons, and any use may be limited by applicable law and regulations. The fund also may hold cash and other short-term investments.

The investment adviser considers both broad economic and issuer specific factors in selecting a portfolio designed to achieve the fund's investment objective. The adviser selects individual securities based upon the terms of the securities (such as yields compared to U.S. Treasuries or comparable issues), liquidity and rating, sector and exposure to particular issuers and sectors. The adviser also employs fundamental research to assess an issuer's credit quality, taking into account financial condition and profitability, future capital needs, potential for change in rating, industry outlook, the competitive environment and management ability. The adviser may sell a portfolio security when it believes the security no longer will contribute to meeting the fund's investment objective. The adviser makes that determination based on the same criteria it uses to select portfolio securities.

The adviser integrates environmental, social and corporate governance (ESG) considerations into its investment research process by evaluating the business models and practices of issuers and their ESG-related risks. The adviser believes ESG analysis is a meaningful facet of fundamental research, the process of evaluating an issuer based on its financial position, business operations, competitive standing and management. This process considers ESG information, where available, in assessing an investment's performance potential. The adviser generally considers ESG information in the context of an issuer's respective sector or industry. The adviser may consider ESG ratings provided by third parties or internal sources, as well as issuer disclosures and public information, in evaluating issuers. ESG considerations are not a primary focus of the fund, and the weight given by the adviser to ESG considerations in making investment decisions will vary and, for any specific decision, they may be given little or no weight. Notwithstanding the foregoing, the adviser generally will not invest fund assets in (i) companies that the adviser determines have significant involvement in the manufacturing of complete

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**Fund summary**

tobacco products, (ii) companies engaged in the production, sale, storage of, or providing services for, certain controversial weapons, including chemical, biological and depleted uranium weapons and certain antipersonnel mines and cluster bombs, or (iii) companies with involvement in the production or sale of nuclear weapons.

**Principal risks of investing in the fund**

You could lose money on your investment in the fund. As with any mutual fund, there is no guarantee that the fund will achieve its objective.

**Market risk.** The market prices of securities or other assets held by the fund may go up or down, sometimes rapidly or unpredictably, due to general market conditions, such as real or perceived adverse economic, political, or regulatory conditions, political instability, recessions, inflation, changes in interest or currency rates, lack of liquidity in the bond markets, the spread of infectious illness or other public health issues, armed conflict, market disruptions caused by tariffs, trade disputes, sanctions or other government actions, or other factors or adverse investor sentiment. If the market prices of the fund's securities and assets fall, the value of your investment will go down. A change in financial condition or other event affecting a single issuer or market may adversely impact securities markets as a whole.

In the past decade, financial markets throughout the world have experienced increased volatility, depressed valuations, decreased liquidity and heightened uncertainty. Governmental and non-governmental issuers have defaulted on, or been forced to restructure, their debts. These conditions may continue, recur, worsen or spread. Events that have contributed to these market conditions include, but are not limited to, major cybersecurity events; geopolitical events (including wars, terror attacks and economic sanctions); measures to address budget deficits; downgrading of sovereign debt; changes in oil and commodity prices; dramatic changes in currency exchange rates; global pandemics; and public sentiment. The fallout from the COVID-19 pandemic and subsequent variants of COVID-19, and the long-term impact on economies, markets, industries and individual issuers, are not known. Some sectors of the economy and individual issuers have experienced or may experience particularly large losses. Periods of extreme volatility in the financial markets; reduced liquidity of many instruments; and disruptions to supply chains, consumer demand and employee availability, may continue for some time.

Raising the ceiling on U.S. government debt has become increasingly politicized. Any failure to increase the ceiling on U.S. government debt could lead to a default on U.S. government obligations, with unpredictable consequences for economies and markets in the U.S. and elsewhere. Recently, inflation and interest rates have increased and may rise further. These circumstances could adversely affect the

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value and liquidity of the fund's investments, impair the fund's ability to satisfy redemption requests, and negatively impact the fund's performance. Following Russia's invasion of Ukraine, Russian securities have lost all, or nearly all, their market value. Other securities or markets could be similarly affected by past or future political, geopolitical or other events or conditions.

Governments and central banks, including the U.S. Federal Reserve, have taken extraordinary and unprecedented actions to support local and global economies and the financial markets. These actions have resulted in significant expansion of public debt, including in the U.S. The consequences of high public debt, including its future impact on the economy and securities markets, may not be known for some time. U.S. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including increases or decreases in interest rates, or contrary actions by different governments, could negatively affect financial markets generally, increase market volatility and reduce the value and liquidity of securities in which the fund invests. Policy and legislative changes in the U.S. and in other countries are affecting many aspects of financial regulation, and these and other events affecting global markets, such as the United Kingdom's exit from the European Union (or Brexit), potential trade imbalances with China or other countries or sanctions or other government actions against Russia, other nations or individuals or companies (or their countermeasures), may contribute to decreased liquidity and increased volatility in the financial markets. The impact of these changes on the markets, and the implications for market participants, may not be fully known for some time.

The United States and other countries are periodically involved in disputes over trade and other matters, which may result in tariffs, investment restrictions and adverse impacts on affected companies and securities. For example, the United States has imposed tariffs and other trade barriers on Chinese exports, has restricted sales of certain categories of goods to China, and has established barriers to investments in China. Trade disputes may adversely affect the economies of the United States and its trading partners, as well as companies directly or indirectly affected and financial markets generally. The United States government has prohibited U.S. persons, such as the fund, from investing in Chinese companies designated as related to the Chinese military. These and possible future restrictions could limit the fund's opportunities for investment and require the sale of securities at a loss or make them illiquid. Moreover, the Chinese government is involved in a longstanding dispute with Taiwan that has included threats of invasion. If the political climate between the United States and China does not improve or continues to deteriorate, if China were to attempt unification of Taiwan by force, or if other geopolitical

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**Fund summary**

conflicts develop or get worse, economies, markets and individual securities may be severely affected both regionally and globally, and the value of the fund's assets may go down.

Economies and financial markets throughout the world are increasingly interconnected. Economic, financial or political events, trading and tariff arrangements, armed conflict including Russia's military invasion of Ukraine, terrorism, natural disasters, infectious illness or public health issues, cybersecurity events, supply chain disruptions, sanctions against Russia, other nations or individuals or companies and possible countermeasures, and other circumstances in one country or region could have profound impacts on other countries or regions and on global economies or markets. As a result, whether or not the fund invests in securities of issuers located in or with significant exposure to the countries or regions directly affected, the value and liquidity of the fund's investments may be negatively affected. The fund may experience a substantial or complete loss on any security or derivative position.

The fund's investments, payment obligations and financing terms may be based on floating rates, such as LIBOR (London Interbank Offered Rate) or Secured Overnight Financing Rate (SOFR). ICE Benchmark Administration, the administrator of LIBOR, ceased publication of most LIBOR settings on a representative basis at the end of 2021 and is expected to cease publication of a majority of U.S. dollar LIBOR settings on a representative basis after June 30, 2023. In addition, global regulators have announced that, with limited exceptions, no new LIBOR-based contracts should be entered into after 2021. The transition away from LIBOR may lead to increased volatility and illiquidity in markets that currently rely on LIBOR and may adversely affect the fund's performance. The transition may also result in a reduction in the value of certain LIBOR-based investments held by the fund or reduce the effectiveness of related transactions such as hedges.

**High yield or "junk" bond risk.** Debt securities that are below investment grade, called "junk bonds," are speculative, have a higher risk of default or are already in default, tend to be less liquid and are more difficult to value than higher grade securities. Junk bonds tend to be volatile and more susceptible to adverse events and negative sentiments. These risks are more pronounced for securities that are already in default.

**Interest rate risk**.The market prices of the fund's fixed income securities may fluctuate significantly when interest rates change. The value of your investment will generally go down when interest rates rise. A rise in rates tends to have a greater impact on the prices of longer term or duration securities. For example, if interest rates increase by 1%, the value of a fund's portfolio with a portfolio duration

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of ten years would be expected to decrease by 10%, all other things being equal. In recent years, interest rates and credit spreads in the U.S. have been at historic lows. The U.S. Federal Reserve has raised certain interest rates, and interest rates may continue to go up. A general rise in interest rates could adversely affect the price and liquidity of fixed income securities and could also result in increased redemptions from the fund. The maturity of a security may be significantly longer than its effective duration. A security's maturity and other features may be more relevant than its effective duration in determining the security's sensitivity to other factors affecting the issuer or markets generally, such as changes in credit quality or in the yield premium that the market may establish for certain types of securities (sometimes called "credit spread"). In general, the longer its maturity the more a security may be susceptible to these factors. When the credit spread for a fixed income security goes up or "widens," the value of the security will generally go down.

Rising interest rates can lead to increased default rates, as issuers of floating rate securities find themselves faced with higher payments. Unlike fixed rate securities, floating rate securities generally will not increase in value if interest rates decline. Changes in interest rates also will affect the amount of interest income the fund earns on its floating rate investments.

**Credit risk.** If an issuer or guarantor of a security held by the fund or a counterparty to a financial contract with the fund defaults on its obligation to pay principal and/or interest, has its credit rating downgraded or is perceived to be less creditworthy, or the credit quality or value of any underlying assets declines, the value of your investment will typically decline. Changes in actual or perceived creditworthiness may occur quickly. The fund could be delayed or hindered in its enforcement of rights against an issuer, guarantor or counterparty.

**Prepayment or call risk.** Many issuers have a right to prepay their securities. If interest rates fall, an issuer may exercise this right. If this happens, the fund will not benefit from the rise in market price that normally accompanies a decline in interest rates, and will be forced to reinvest prepayment proceeds at a time when yields on securities available in the market are lower than the yield on the prepaid security. The fund also may lose any premium it paid on the security.

**Extension risk.** During periods of rising interest rates, the average life of certain types of securities may be extended because of slower than expected principal payments. This may lock in a below market interest rate, increase the security's duration and reduce the value of the security.

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**Fund summary**

**Liquidity risk.** Some securities and derivatives held by the fund may be or become impossible or difficult to purchase, sell or unwind, particularly during times of market turmoil. An instrument's liquidity may be affected by reduced trading volume, a relative lack of market makers or legal restrictions, and illiquid securities and derivatives also may be difficult to value. Liquidity risk may be magnified in an environment of rising interest rates or widening credit spreads. During times of market turmoil, there have been, and may be, no buyers or sellers for securities in entire asset classes. If the fund is forced to sell an illiquid asset or unwind a derivative position to meet redemption requests or other cash needs, or to try to limit losses, the fund may be forced to sell at a substantial loss or may not be able to sell at all. The fund may not receive its proceeds from the sale of certain securities for an extended period (for example, several weeks or even longer). In extreme cases, this may constrain the fund's ability to meet its obligations (including obligations to redeeming shareholders).

**Portfolio selection risk.** The adviser's judgment about the quality, relative yield, relative value or market trends affecting a particular sector or region, market segment, security, industry or about interest rates or other market factors may prove to be incorrect or may not produce the desired results, or there may be imperfections, errors or limitations in the models, tools and information used by the adviser.

**ESG risk.** The fund's adviser may consider ESG information in its investment research process. This may mean forgoing some investment opportunities available to funds that do not consider ESG information. In considering ESG information, the adviser may use third party ESG ratings information that it believes to be reliable, but such information may not be accurate or complete, or may be biased. ESG considerations are not a primary focus of the fund, and the weight given by the adviser to ESG considerations in making investment decisions will vary and, for any specific decision, they may be given little or no weight.

**Risks of investing in loans.** Floating rate loans and similar investments may be illiquid or less liquid than other investments and difficult to value. Market quotations for these securities may be volatile and/or subject to large spreads between bid and ask prices. No active trading market may exist for many floating rate loans, and many loans are subject to restrictions on resale. Any secondary market may be subject to irregular trading activity and extended trade settlement periods. In particular, loans may take longer than seven days to settle, potentially leading to the sale proceeds of loans not being available to meet redemptions for a substantial period of time after the sale of the loans. To the extent that sale proceeds of loans are not available, the fund may sell securities that have shorter settlement periods

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or may access other sources of liquidity to meet redemption requests. There is less readily available, reliable information about most senior loans than is the case for many other types of securities. Loans may not be considered "securities," and purchasers, such as the fund, therefore may not be entitled to rely on the anti-fraud protections afforded by federal securities laws.

**Collateral risk.** The value of collateral, if any, securing a floating rate loan can decline, and may be insufficient to meet the issuer's obligations or may be difficult to liquidate. In addition, the fund's access to collateral may be limited by bankruptcy or other insolvency laws. Uncollateralized loans involve a greater risk of loss.

**Risk of disadvantaged access to confidential information.** The adviser's decision not to receive material, non-public information about an issuer of a loan either held by, or considered for investment by, the fund, under normal circumstances could place it at a disadvantage, relative to other loan investors, in assessing a loan or the loan's issuer, and adversely affect the fund's investment performance.

**Risks of subordinated securities.** A holder of securities that are subordinated or "junior" to more senior securities of an issuer is entitled to payment after holders of more senior securities of the issuer. Subordinated securities are more likely to suffer a credit loss than non-subordinated securities of the same issuer, any loss incurred by the subordinated securities is likely to be proportionately greater, and any recovery of interest or principal may take more time. As a result, even a perceived decline in creditworthiness of the issuer is likely to have a greater impact on subordinated securities than more senior securities.

**U.S. Treasury obligations risk.** The market value of direct obligations of the U.S. Treasury may vary due to changes in interest rates. In addition, changes to the financial condition or credit rating of the U.S. government may cause the value of the fund's investments in obligations issued by the U.S. Treasury to decline.

**U.S. government agency obligations risk.** The fund invests in obligations issued by agencies and instrumentalities of the U.S. government. Government-sponsored entities such as the Federal National Mortgage Association (FNMA), the Federal Home Loan Mortgage Corporation (FHLMC) and the Federal Home Loan Banks (FHLBs), although chartered or sponsored by Congress, are not funded by congressional appropriations and the debt and mortgage-backed securities issued by them are neither guaranteed nor issued by the U.S. government. The maximum potential liability of the issuers of some U.S. government obligations may greatly exceed their current resources, including any legal right to support from the U.S. government. Such debt and mortgage-backed securities are subject to the risk of default on the payment of interest and/or principal, similar to debt of

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**Fund summary**

private issuers. Although the U.S. government has provided financial support to FNMA and FHLMC in the past, there can be no assurance that it will support these or other government-sponsored entities in the future.

**Mortgage-related and asset-backed securities risk.** The value of mortgage-related securities, including commercial mortgage-backed securities, collateralized mortgage-backed securities, credit risk transfer securities, and asset-backed securities, will be influenced by factors affecting the assets underlying such securities. As a result, during periods of declining asset value, difficult or frozen credit markets, swings in interest rates, or deteriorating economic conditions, mortgage-related and asset-backed securities may decline in value, face valuation difficulties, become more volatile and/or become illiquid. Mortgage-backed securities tend to be more sensitive to changes in interest rates than other types of debt securities. These securities are also subject to interest rate, prepayment and extension risks. Some of these securities may receive little or no collateral protection from the underlying assets and are thus subject to the risk of default. The risk of such defaults is generally higher in the case of mortgage-backed investments offered by non-governmental issuers and those that include so-called "sub-prime" mortgages. The structure of some of these securities may be complex and there may be less available information than for other types of debt securities. Upon the occurrence of certain triggering events or defaults, the fund may become the holder of underlying assets at a time when those assets may be difficult to sell or may be sold only at a loss.

**Risks of investing in collateralized debt obligations.** Investment in a collateralized debt obligation (CDO) is subject to the credit, subordination, interest rate, valuation, prepayment, extension and other risks of the obligations underlying the CDO and the tranche of the CDO in which the fund invests. CDOs are subject to liquidity risk. Synthetic CDOs are also subject to the risks of investing in derivatives, such as credit default swaps, and leverage risk.

**Risks of instruments that allow for balloon payments or negative amortization payments.** Certain debt instruments allow for balloon payments or negative amortization payments. Such instruments permit the borrower to avoid paying currently a portion of the interest accruing on the instrument. While these features make the debt instrument more affordable to the borrower in the near term, they increase the risk that the borrower will be unable to make the resulting higher payment or payments that become due at the maturity of the loan.

**Risks of investing in insurance-linked securities.** The fund could lose a portion or all of the principal it has invested in an insurance-linked security, and the right to additional interest and/or dividend payments with respect to the security,

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upon the occurrence of one or more trigger events, as defined within the terms of an insurance-linked security. Trigger events may include natural or other perils of a specific size or magnitude that occur in a designated geographic region during a specified time period, and/or that involve losses or other metrics that exceed a specific amount. The fund may also invest in insurance-linked securities that are subject to "indemnity triggers." An indemnity trigger is a trigger based on the actual losses of the ceding sponsor (i.e., the party seeking reinsurance). Insurance-linked securities subject to indemnity triggers are often regarded as being subject to potential moral hazard, since such insurance-linked securities are triggered by actual losses of the ceding sponsor and the ceding sponsor may have an incentive to take actions and/or risks that would have an adverse effect on the fund. There is no way to accurately predict whether a trigger event will occur and, accordingly, insurance-linked securities carry significant risk. In addition to the specified trigger events, insurance-linked securities may expose the fund to other risks, including but not limited to issuer (credit) default, adverse regulatory or jurisdictional interpretations and adverse tax consequences. Certain insurance-linked securities may have limited liquidity, or may be illiquid. The fund has limited transparency into the individual contracts underlying certain insurance-linked securities, which may make the risk assessment of such securities more difficult. Certain insurance-linked securities may be difficult to value.

**Risks of zero coupon bonds, payment in kind, deferred and contingent payment securities.** These securities may be more speculative and may fluctuate more in value than securities which pay income periodically and in cash. In addition, although the fund receives no periodic cash payments on such securities, the fund is deemed for tax purposes to receive income from such securities, which applicable tax rules require the fund to distribute to shareholders. Such distributions may be taxable when distributed to shareholders.

**Risks of non-U.S. investments.** Investing in non-U.S. issuers, or in U.S. issuers that have significant exposure to foreign markets, may involve unique risks compared to investing in securities of U.S. issuers. These risks are more pronounced for issuers in emerging markets or to the extent that the fund invests significantly in one region or country. These risks may include different financial reporting practices and regulatory standards, less liquid trading markets, extreme price volatility, currency risks, changes in economic, political, regulatory and social conditions, military conflicts and sanctions, terrorism, sustained economic downturns, financial instability, reduction of government or central bank support, inadequate accounting standards, tariffs, tax disputes or other tax burdens, nationalization or expropriation of assets, arbitrary application of laws and regulations or lack of rule of law, and investment and repatriation restrictions. Lack of information and less market

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**Fund summary**

regulation also may affect the value of these securities. Withholding and other non-U.S. taxes may decrease the fund's return. Non-U.S. issuers may be located in parts of the world that have historically been prone to natural disasters. Emerging market economies tend to be less diversified than those of more developed countries. They typically have fewer medical and economic resources than more developed countries and thus they may be less able to control or mitigate the effects of a pandemic. Investing in depositary receipts is subject to many of the same risks as investing directly in non-U.S. issuers. Depositary receipts may involve higher expenses and may trade at a discount (or premium) to the underlying security.

A number of countries in the European Union (EU) have experienced, and may continue to experience, severe economic and financial difficulties. In addition, the United Kingdom has withdrawn from the EU (commonly known as "Brexit"). The range and potential implications of possible political, regulatory, economic, and market outcomes of Brexit cannot be fully known but could be significant, potentially resulting in increased volatility, illiquidity and potentially lower economic growth in the affected markets, which will adversely affect the fund's investments.

If one or more stockholders of a supranational entity such as the World Bank fail to make necessary additional capital contributions, the entity may be unable to pay interest or repay principal on its debt securities. <br>

Sanctions or other government actions against certain countries could negatively impact the fund's investments in securities that have exposure to those countries. Circumstances that impact one country could have profound impacts on other countries and on global economies or markets. China and other developing market countries may be subject to considerable degrees of economic, political and social instability. The U.S. government has imposed restrictions on U.S. investor participation in certain Chinese investments. These matters could adversely affect China's economy. In addition, China's long-running conflict over Taiwan's sovereignty, border disputes with many neighbors and historically strained relations with other Asian countries could result in military conflict that could adversely impact the economies of China and other Asian countries, disrupt supply chains, and severely affect global economies and markets.

Russia launched a large-scale invasion of Ukraine on February 24, 2022. In response to the military action by Russia, various countries, including the U.S., the United Kingdom, and European Union, issued broad-ranging economic sanctions against Russia and Belarus and certain companies and individuals. Russia has taken retaliatory actions, including preventing repatriation of capital by U.S. and other investors. Since then, Russian securities have lost all, or nearly all, their market value, and many other issuers, securities and markets have been adversely affected. The ongoing

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conflict has resulted in significant market disruptions, including in certain markets, industries and sectors, such as the oil and natural gas markets, and negatively affected global supply chains, food supplies, inflation and global growth. The U.S. and other countries may impose sanctions on other countries, companies and individuals in light of Russia's military invasion. The extent and duration of the military action or future escalation of such hostilities, the extent and impact of existing and future sanctions, market disruptions and volatility, and the result of any diplomatic negotiations cannot be predicted. These and any related events could have a significant impact on the value and liquidity of certain fund investments, on fund performance and the value of an investment in the fund.

**Currency risk.** The fund could experience losses based on changes in the exchange rate between non-U.S. currencies and the U.S. dollar or as a result of currency conversion costs. Currency exchange rates can be volatile, and are affected by factors such as general economic conditions, the actions of the U.S. and foreign governments or central banks, the imposition of currency controls and speculation.

**Equity securities risk.** Equity securities represent an ownership interest in an issuer, rank junior in a company's capital structure to debt securities and consequently may entail greater risk of loss than debt securities. Equity securities are subject to the risk that stock prices may rise and fall in periodic cycles and may perform poorly relative to other investments. This risk may be greater in the short term.

**Risks of convertible securities.** The market values of convertible securities tend to decline as interest rates increase and, conversely, to increase as interest rates decline. A downturn in equity markets may cause the price of convertible securities to decrease relative to other fixed income securities.

**Preferred stocks risk.** Preferred stocks may pay fixed or adjustable rates of return. Preferred stocks are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company's preferred stocks generally pay dividends only after the company makes required payments to holders of its bonds and other debt. Thus, the value of preferred stocks will usually react more strongly than bonds and other debt to actual or perceived changes in the company's financial condition or prospects. The market value of preferred stocks generally decreases when interest rates rise. Also, the market prices of preferred stocks are more sensitive to changes in the issuer's creditworthiness than are the prices of debt securities. Generally, under normal circumstances, preferred stocks do not carry voting rights. Preferred stocks may trade less frequently and in a more limited volume and may be subject to more abrupt or erratic price movements than other securities. Preferred stocks of smaller companies may be more vulnerable to adverse developments than preferred stocks of larger companies.

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**Fund summary**

**Risks of investment in other funds.** Investing in other investment companies, including exchange-traded funds (ETFs) and closed-end funds, subjects the fund to the risks of investing in the underlying securities or assets held by those funds. When investing in another fund, the fund will bear a pro rata portion of the underlying fund's expenses, including management fees, in addition to its own expenses. ETFs and closed-end funds are bought and sold based on market prices and can trade at a premium or a discount to the ETF's or closed-end fund's net asset value. Such funds may trade at a discount for an extended period and may not ever realize their net asset value.

**Derivatives risk.** Using swaps, forward foreign currency exchange contracts, bond and interest rate futures and other derivatives can increase fund losses and reduce opportunities for gains when market prices, interest rates, currencies or the derivative instruments themselves behave in a way not anticipated by the fund. Using derivatives may increase the volatility of the fund's net asset value and may not provide the result intended. Derivatives may have a leveraging effect on the fund. Some derivatives have the potential for unlimited loss, regardless of the size of the fund's initial investment. Derivatives are generally subject to the risks applicable to the assets, rates, indices or other indicators underlying the derivative. Changes in a derivative's value may not correlate well with the referenced asset or metric. The fund also may have to sell assets at inopportune times to satisfy its obligations. Derivatives may be difficult to sell, unwind or value, and the counterparty may default on its obligations to the fund. Use of derivatives may have different tax consequences for the fund than an investment in the underlying security, and such differences may affect the amount, timing and character of income distributed to shareholders. The U.S. government and foreign governments have adopted and implemented or are in the process of adopting and implementing regulations governing derivatives markets, including mandatory clearing of certain derivatives, margin and reporting requirements. The ultimate impact of the regulations remains unclear. Additional regulation of derivatives may make them more costly, limit their availability or utility, otherwise adversely affect their performance or disrupt markets.

**Credit default swap risk.** Credit default swap contracts, a type of derivative instrument, involve special risks and may result in losses to the fund. Credit default swaps may in some cases be illiquid, and they increase credit risk since the fund has exposure to the issuer of the referenced obligation and either the counterparty to the credit default swap or, if it is a cleared transaction, the brokerage firm through which the trade was cleared and the clearing organization that is the counterparty to that trade.

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**Structured securities risk.** Structured securities may behave in ways not anticipated by the fund, or they may not receive the tax, accounting or regulatory treatment anticipated by the fund.

**Risks of investing in inverse floating rate obligations.** The interest rate on inverse floating rate obligations will generally decrease as short-term interest rates increase, and increase as short-term rates decrease. Due to their leveraged structure, the sensitivity of the market value of an inverse floating rate obligation to changes in interest rates is generally greater than a comparable long-term bond issued by the same issuer and with similar credit quality, redemption and maturity provisions. Inverse floating rate obligations may be volatile and involve leverage risk.

**Forward foreign currency transactions risk.** The fund may not fully benefit from or may lose money on forward foreign currency transactions if changes in currency rates do not occur as anticipated or do not correspond accurately to changes in the value of the fund's holdings, or if the counterparty defaults. Such transactions may also prevent the fund from realizing profits on favorable movements in exchange rates. Risk of counterparty default is greater for counterparties located in emerging markets.

**Leveraging risk.** The value of your investment may be more volatile and other risks tend to be compounded if the fund borrows or uses derivatives or other investments, such as ETFs, that have embedded leverage. Leverage generally magnifies the effect of any increase or decrease in the value of the fund's underlying assets and creates a risk of loss of value on a larger pool of assets than the fund would otherwise have, potentially resulting in the loss of all assets. Engaging in such transactions may cause the fund to liquidate positions when it may not be advantageous to do so to satisfy its obligations. New derivatives regulations require the fund, to the extent it uses derivatives to a material extent, to, among other things, comply with certain overall limits on leverage. These regulations may limit the ability of the fund to pursue its investment strategies and may not be effective to mitigate the fund's risk of loss from derivatives.

**Repurchase agreement risk.** In the event that the other party to a repurchase agreement defaults on its obligations, the fund may encounter delay and incur costs before being able to sell the security. Such a delay may involve loss of interest or a decline in price of the security. In addition, if the fund is characterized by a court as an unsecured creditor, it would be at risk of losing some or all of the principal and interest involved in the transaction.

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**Fund summary**

**Market segment risk.** To the extent the fund emphasizes, from time to time, investments in a market segment, the fund will be subject to a greater degree to the risks particular to that segment, and may experience greater market fluctuation than a fund without the same focus.

Industries in the financials segment, such as banks, insurance companies, broker-dealers and real estate investment trusts (REITs), may be sensitive to changes in interest rates, credit rating downgrades, decreased liquidity in credit markets, and general economic activity and are generally subject to extensive government regulation.

**Valuation risk.** Nearly all of the fund's investments are valued using a fair value methodology. The sales price the fund could receive for any particular portfolio investment may differ from the fund's valuation of the investment, particularly for illiquid securities and securities that trade in thin or volatile markets. These differences may increase significantly and affect fund investments more broadly during periods of market volatility. Investors who purchase or redeem fund shares may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the securities had not been fair-valued or if a different valuation methodology had been used. The fund's ability to value its investments may also be impacted by technological issues and/or errors by pricing services or other third party service providers.

**Redemption risk.** The fund may experience heavy redemptions that could cause the fund to liquidate its assets at inopportune times or at a loss or depressed value, or accelerate taxable gains or transaction costs, which could cause the value of your investment to decline.

**Cybersecurity risk.** Cybersecurity failures by and breaches of the fund's adviser, transfer agent, distributor, custodian, fund accounting agent or other service providers may disrupt fund operations, interfere with the fund's ability to calculate its NAV, prevent fund shareholders from purchasing, redeeming or exchanging shares or receiving distributions or receiving timely information regarding the fund or their investment in the fund, cause loss of or unauthorized access to private shareholder information, and result in financial losses to the fund and its shareholders, regulatory fines, penalties, reputational damage, or additional compliance costs.

**Expense risk.** Your actual costs of investing in the fund may be higher than the expenses shown in "Annual fund operating expenses" for a variety of reasons. For example, expense ratios may be higher than those shown if overall net assets decrease. Net assets are more likely to decrease and fund expense ratios are more likely to increase when markets are volatile.

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Please note that there are many other factors that could adversely affect your investment and that could prevent the fund from achieving its goals.

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 government agency.

**The fund's past performance**

The bar chart and table indicate the risks and volatility of an investment in the fund by showing how the fund has performed in the past. The bar chart shows changes in the performance of the fund's Class A shares from calendar year to calendar year. The table shows the average annual total returns for each class of the fund over time and compares these returns to the returns of the Morningstar LSTA US Performing Loan Index, a broad-based measure of market performance that has characteristics relevant to the fund's investment strategies. <br> You can obtain updated performance information by visiting https://www.amundi.com/usinvestors/Products/Mutual-Funds or by calling 1-800-225-6292.

The fund's past performance (before and after taxes) does not necessarily indicate how it will perform in the future.

The bar chart does not reflect any sales charge you may pay when you buy fund shares. If this amount was reflected, returns would be less than those shown.

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**Fund summary**

**Annual return Class A shares (%)**

(Year ended December 31)

![](floatrate.jpg)

For the period covered by the bar chart:

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| | | | |
|:---|:---|:---|:---|
|  | **Returns** | **Period Beginning** | **Period Ending** |
| Highest Calendar Quarter | &nbsp;&nbsp;&nbsp; 7.40% | 04/01/2020 to | 06/30/2020 |
| Lowest Calendar Quarter | -12.39% | 01/01/2020 to | 03/31/2020 |

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No performance information is presented for Class K shares because no Class K shares were outstanding during the most recent calendar year. Class K shares were in operation from December 10, 2013 through October 4, 2017. The returns for Class K would differ from those of other classes of shares because they have different expenses.

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**Average annual total return (%)**

(for periods ended December 31, 2022)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **1 Year** | **5 Years** | **10 Years** | **Since**<br> **Inception**<br>| **Inception**<br> **Date** <br>|
| Class A |  |  |  |  | 2/14/07 |
| Return before taxes | -7.66 | 0.74 | 1.92 | 2.69 |  |
| Return after taxes on distributions | -9.65 | -0.97 | 0.27 | 0.95 |  |
| Return after taxes on distributions and <br> sale of shares<br>| -4.53 | -0.15 | 0.73 | 1.31 |  |
| Class C | -4.82 | 1.08 | 1.72 | 2.24 | 2/14/07 |
| Class Y | -2.88 | 2.18 | 2.83 | 3.32 | 2/14/07 |
| Morningstar LSTA US Performing Loan <br> Index (reflects no deduction for fees, <br> expenses or taxes) <br>| -0.61 | 3.47 | 3.90 | 4.33 | 2/14/07 |

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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. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who hold fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns after taxes on distributions and sale of fund shares are higher than returns before taxes for certain periods shown because they reflect the tax benefit of capital losses realized on the sale of fund shares.

After-tax returns are shown only for Class A shares. After-tax returns for Class C, Class K and Class Y shares will vary.

**Management** 

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| | |
|:---|:---|
| **Investment adviser** | Amundi Asset Management US, Inc. ("Amundi <br> US")<br>|
| **Portfolio management** | Jonathan Sharkey, Senior Vice President of Amundi <br> US (portfolio manager of the fund since 2007)<br>|

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**Purchase and sale of fund shares**

You may purchase, exchange or sell (redeem) shares each day the New York Stock Exchange is open through your financial intermediary or, for accounts held directly with the fund, by contacting the fund in writing or by telephone: Pioneer Funds, P.O. Box 534427, Pittsburgh, PA 15253-4427, tel. 1-800-225-6292.

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**Fund summary**

Your initial investment for Class A or Class C shares must be at least $1,000. Additional investments must be at least $100 for Class A shares and $500 for Class C shares. Generally, the initial investment for Class K or Class Y shares must be at least $5 million. This amount may be invested in one or more of the Pioneer mutual funds that currently offer Class K or Class Y shares, as applicable. There is no minimum additional investment amount for Class K or Class Y shares.

**Tax information**

The fund intends to make distributions that may be taxed as ordinary income or capital gains.

**Payments to broker-dealers and other financial intermediaries**

If you purchase the fund through a broker-dealer or other financial intermediary (such as a bank), the fund and its related companies may pay the intermediary for the sale of fund shares and related services. These payments create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson or investment professional to recommend the fund over another investment. Ask your salesperson or investment professional or visit your financial intermediary's website for more information.

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**More on the fund's investment objective and strategies**

**Investment objective**

A high level of current income.

The fund's investment objective may be changed without shareholder approval. The fund will provide at least 30 days' written notice prior to implementing any change to its investment objective.

**Principal investment strategies**

Normally, the fund invests at least 80% of its net assets (plus the amount of borrowings, if any, for investment purposes) in floating rate loans and other floating rate investments. Derivative instruments that provide exposure to such floating rate securities or have similar economic characteristics may be used to satisfy the fund's 80% policy. Floating rate investments are securities and other instruments with interest rates that adjust or "float" periodically based on a specified interest rate or other reference and include senior secured floating rate loans, repurchase agreements, money market securities and shares of money market and short term bond funds. The fund also considers as floating rate instruments, and the fund may invest without limit in, adjustable rate securities, fixed rate securities with durations of less than or equal to one year, securities of other investment companies (including mutual funds, exchange-traded funds and closed-end funds) that invest primarily in floating rate instruments, and fixed rate securities with respect to which the fund has entered into derivative instruments to effectively convert the fixed rate interest payments into floating rate interest payments. The fund considers these investments as economic equivalents of floating rate instruments.

Floating rate loans typically are rated below investment grade (debt securities rated below investment grade are commonly referred to as "junk bonds"). The fund's investments in floating rate loans typically hold a senior position in the borrower's capital structure, but may also include unsecured or subordinated loans.

The fund will provide written notice to shareholders at least 60 days prior to any change to the requirement that it invest at least 80% of its assets in floating rate loans and other floating rate investments.

The fund's investments also may include revolving credit facility loans, high yield corporate bonds (also known as "junk bonds"), investment grade fixed income debt securities, preferred stocks and convertible securities. The fund may receive debt securities or equity securities as a result of the general restructuring of the debt of an issuer, the restructuring of a floating rate loan, or as part of a package of securities acquired with a loan.

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**More on the fund's investment objective and strategies**

The fund may invest up to 35% of its total assets in debt securities of non-U.S. issuers, including emerging market issuers. The fund does not currently intend to invest more than 25% of its total assets in any one non-U.S. country. The fund does not count securities of Canadian issuers against the limit on investment in securities of non-U.S. issuers.

The fund may invest without limit in securities of any rating, including those of issuers that are in default. The fund does not have a targeted maturity range for its portfolio. The fund invests in securities of any maturity. The maturity of a fixed income security is a measure of the time remaining until final payment on the security is due. The fund's investments may have fixed or variable principal payments and all types of interest rate and dividend payment and reset terms, including fixed rate, adjustable rate, floating rate, contingent, deferred, payment in kind and auction rate features. The fund has the ability to invest in a broad range of issuers and segments of the debt securities market. The fund may invest in securities of issuers in any market capitalization range, industry or market sector.

The fund may invest in mortgage-related securities, including commercial mortgage-backed securities, collateralized mortgage obligations, credit risk transfer securities and "sub-prime" mortgages and asset-backed securities. The fund's investments in mortgage-related securities may include instruments, the underlying assets of which allow for balloon payments (where a substantial portion of a mortgage loan balance is paid at maturity, which can shorten the average life of the mortgage-backed instrument) or negative amortization payments (where as a result of a payment cap, payments on a mortgage loan are less than the amount of principal and interest owed, with excess amounts added to the outstanding principal balance, which can extend the average life of the mortgage-backed instrument).

The fund also may invest in U.S. government securities, zero coupon securities, subordinated debt securities and insurance-linked securities.

Amundi Asset Management US, Inc. ("Amundi US" or "the adviser") considers both broad economic and issuer specific factors in selecting a portfolio designed to achieve the fund's investment objective. Amundi US selects individual securities based upon the terms of the securities (such as yields compared to U.S. Treasuries or comparable issues), liquidity and rating, sector and exposure to particular issuers and sectors. Amundi US also employs fundamental research to assess an issuer's credit quality, taking into account financial condition and profitability, future capital needs, potential for change in rating, industry outlook, the competitive environment and management ability. In making these portfolio decisions, Amundi US relies on the knowledge, experience and judgment of its staff and the staff of its affiliates who have access to a wide variety of research. Amundi US may sell a

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portfolio security when it believes the security no longer will contribute to meeting the fund's investment objective. Amundi US makes that determination based on the same criteria it uses to select portfolio securities.

The adviser integrates environmental, social and corporate governance (ESG) considerations into its investment research process by evaluating the business models and practices of issuers and their ESG-related risks. The adviser believes ESG analysis is a meaningful facet of fundamental research, the process of evaluating an issuer based on its financial position, business operations, competitive standing and management. This process considers ESG information, where available, in assessing an investment's performance potential. The adviser generally considers ESG information in the context of an issuer's respective sector or industry. The adviser may consider ESG ratings provided by third parties or internal sources, as well as issuer disclosures and public information, in evaluating issuers. ESG considerations are not a primary focus of the fund, and the weight given by the adviser to ESG considerations in making investment decisions will vary and, for any specific decision, they may be given little or no weight.

Notwithstanding the foregoing, the adviser generally will not invest fund assets in:

• companies that the adviser determines have significant involvement in the manufacturing of complete tobacco products;

• companies engaged in (i) the production, sale or storage of chemical, biological and depleted uranium weapons, or (ii) the production, sale, storage of, or providing services for, antipersonnel mines and cluster bombs prohibited by the Ottawa and Oslo treaties; or

• companies (i) with involvement in the production, sale or storage of nuclear weapons of countries that are non-parties to the Treaty on the Non-Proliferation of Nuclear Weapons, (ii) with involvement in the production of nuclear warheads and/or whole nuclear missiles; or (iii) that the adviser determines have significant involvement in the production or sale of nuclear weapons.

The fund's investment strategies and policies may be changed from time to time without shareholder approval, unless specifically stated otherwise in this prospectus or in the statement of additional information.

**Floating rate investments**

Floating rate investments are securities and other instruments with interest rates that adjust or "float" periodically based on a specified interest rate or other reference and include floating rate loans, repurchase agreements, money market securities and shares of money market and short-term bond funds.

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**More on the fund's investment objective and strategies**

**Floating rate loans**

Floating rate loans are provided by banks and other financial institutions to large corporate customers in connection with recapitalizations, acquisitions, and refinancings. These loans are generally acquired as a participation interest in, or assignment of, loans originated by a lender or other financial institution. These loans are rated below investment grade. The rates of interest on the loans typically adjust periodically by reference to a base lending rate, such as the London Interbank Offered Rate (LIBOR) or Secured Overnight Financing Rate (SOFR), a designated U.S. bank's prime or base rate or the overnight federal funds rate, plus a premium. Some loans reset on set dates, typically every 30 to 90 days, but not to exceed one year. Other loans reset periodically when the underlying rate resets.

In most instances, the fund's investments in floating rate loans hold a senior position in the capital structure of the borrower. Having a senior position means that, if the borrower becomes insolvent, senior debtholders, like the fund, will be paid before subordinated debtholders and stockholders of the borrower. Senior loans typically are secured by specific collateral.

Floating rate loans typically are structured and administered by a financial institution that acts as an agent for the holders of the loan. Loans can be acquired directly through the agent, by assignment from another holder of the loan, or as a participation interest in the loan. When the fund is a direct investor in a loan, the fund may have the ability to influence the terms of the loan, although the fund does not act as the sole negotiator or originator of the loan. Participation interests are fractional interests in a loan issued by a lender or other financial institution. When the fund invests in a loan participation, the fund does not have a direct claim against the borrower and must rely upon an intermediate participant to enforce any rights against the borrower.

**Second lien loans and other subordinated securities**

The fund may invest in second lien loans and other securities that are subordinated or "junior" to more senior securities of the issuer. The investor in a subordinated security of an issuer is entitled to payment after other holders of debt in that issuer.

**Investment grade securities**

A debt security is considered investment grade if it is:

• Rated BBB or higher at the time of purchase by Standard & Poor's Financial Services LLC;

• Rated the equivalent rating by a nationally recognized statistical rating organization; or

• Determined to be of equivalent credit quality by Amundi US.

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Securities in the lowest category of investment grade (i.e., BBB) are considered to have speculative characteristics. An investor can still lose significant amounts when investing in investment grade securities.

**Below investment grade securities ("junk bonds")**

The fund may invest in debt securities rated below investment grade or, if unrated, of equivalent quality as determined by Amundi US. A debt security is below investment grade if it is rated BB or lower by Standard & Poor's Financial Services LLC or the equivalent rating by another nationally recognized statistical rating organization or determined to be of equivalent credit quality by Amundi US. Debt securities rated below investment grade are commonly referred to as "junk bonds" and are considered speculative. Below investment grade debt securities involve greater risk of loss, are subject to greater price volatility and are less liquid, especially during periods of economic uncertainty or change, than higher quality debt securities. Below investment grade securities also may be more difficult to value.

**Debt rating considerations**

For purposes of the fund's credit quality policies, if a security receives different ratings from nationally recognized statistical rating organizations, the fund will use the rating chosen by the portfolio manager as most representative of the security's credit quality. The ratings of nationally recognized statistical rating organizations represent their opinions as to the quality of the securities that they undertake to rate and may not accurately describe the risks of the securities. A rating organization may have a conflict of interest with respect to a security for which it assigns a quality rating. In addition, there may be a delay between a change in the credit quality of a security or other asset and a change in the quality rating assigned to the security or other asset by a rating organization. If a rating organization changes the quality rating assigned to one or more of the fund's securities, Amundi US will consider if any action is appropriate in light of the fund's investment objective and policies. These ratings are used as criteria for the selection of portfolio securities, in addition to Amundi US's own assessment of the credit quality of potential investments.

**Non-U.S. investments**

The fund may invest in securities of non-U.S. issuers, including securities of emerging markets issuers. Non-U.S. issuers are issuers that are organized and have their principal offices outside of the United States. Non-U.S. securities may be issued by non-U.S. governments, banks or corporations, or private issuers, and certain supranational organizations, such as the World Bank and the European Union. The fund considers emerging market issuers to include issuers organized under the laws of an emerging market country, issuers with a principal office in an emerging

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**More on the fund's investment objective and strategies**

market country, issuers that derive at least 50% of their gross revenues or profits from goods or services produced in emerging market countries or sales made in emerging market countries, or issuers that have at least 50% of their assets in emerging market countries. Emerging markets generally will include, but not be limited to, countries included in the Morgan Stanley Capital International (MSCI) Emerging + Frontier Markets Index.

**U.S. government securities**

The fund may invest in U.S. government securities. U.S. government securities are obligations of, or guaranteed by, the U.S. government, its agencies or government-sponsored entities. U.S. government securities include obligations: directly issued by or supported by the full faith and credit of the U.S. government, like Treasury bills, notes and bonds and Government National Mortgage Association (GNMA) certificates; supported by the right of the issuer to borrow from the U.S. Treasury, like those of the Federal Home Loan Banks (FHLBs); supported by the discretionary authority of the U.S. government to purchase the agency's securities, like those of the Federal National Mortgage Association (FNMA); or supported only by the credit of the issuer itself, like the Tennessee Valley Authority. U.S. government securities include issues by non-governmental entities (like financial institutions) that carry direct guarantees from U.S. government agencies. U.S. government securities include zero coupon securities that make payments of interest and principal only upon maturity and which therefore tend to be subject to greater volatility than interest-bearing securities with comparable maturities.

Although the U.S. government guarantees principal and interest payments on securities issued by the U.S. government and some of its agencies, such as securities issued by GNMA, this guarantee does not apply to losses resulting from declines in the market value of these securities. Some of the U.S. government securities that the fund may hold are not guaranteed or backed by the full faith and credit of the U.S. government, such as those issued by FNMA and the Federal Home Loan Mortgage Corporation (FHLMC).

**Mortgage-backed securities**

The fund may invest in mortgage-backed securities. Mortgage-backed securities may be issued by private issuers, by government-sponsored entities, such as FNMA or FHLMC, or by agencies of the U.S. government, such as GNMA. Mortgage-backed securities represent direct or indirect participation in, or are collateralized by and payable from, mortgage loans secured by real property. The fund's investments in mortgage-related securities may include mortgage derivatives and structured securities.

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The fund may invest in collateralized mortgage obligations (CMOs). A CMO is a mortgage-backed bond that is issued in multiple classes, each with a specified fixed or floating interest rate and a final scheduled distribution date. The holder of an interest in a CMO is entitled to receive specified cash flows from a pool of underlying mortgages or other mortgage-backed securities. Depending upon the class of CMO purchased, the holder may be entitled to payment before the cash flow from the pool is used to pay holders of other classes of the CMO or, alternatively, the holder may be paid only to the extent that there is cash remaining after the cash flow has been used to pay other classes. A subordinated interest may serve as a credit support for the senior securities purchased by other investors.

The fund may invest in commercial mortgage-backed securities ("CMBS"). CMBS are subject to the risks generally associated with mortgage-backed securities. CMBS may not be backed by the full faith and credit of the U.S. government and are subject to risk of default on the underlying mortgages. CMBS issued by non-government entities may offer higher yields than those issued by government entities, but also may be subject to greater volatility than government issues. CMBS react differently to changes in interest rates than other bonds and the prices of CMBS may reflect adverse economic and market conditions. Small movements in interest rates (both increases and decreases) may quickly and significantly reduce the value of CMBS.

The commercial mortgages underlying certain commercial mortgage-backed securities generally allow all or a substantial portion of the loan balance to be paid at maturity, commonly known as a balloon payment. Some mortgage loans restrict periodic adjustments by limiting changes in the borrower's monthly principal and interest payments rather than limiting interest rate changes. These payment caps may result in negative amortization, where payments are less than the amount of principal and interest owed, with excess amounts added to the outstanding principal balance, which can extend the average life of the mortgage-backed securities.

The fund may invest in credit risk transfer securities. Credit risk transfer securities are a type of mortgage-related security that transfers the credit risk related to certain types of mortgage-backed securities to the owner of the credit risk transfer security. Credit risk transfer securities are commonly issued by government-sponsored enterprises (GSEs), such as FNMA or FHLMC, but may also be issued by private entities such as banks or other financial institutions. Credit risk transfer securities issued by GSEs are unguaranteed and unsecured fixed or floating rate general obligations and are typically issued at par and have stated final maturities. In addition, GSE-issued credit risk transfer securities are structured so that: (i) interest is paid directly by the issuing GSE; and (ii) principal is paid by the issuing GSE in

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accordance with the principal payments and default performance of a pool of residential mortgage loans acquired by the GSE. In this regard, holders of GSE credit risk transfer securities receive compensation for providing credit protection to the GSE and, when a specified level of losses on the underlying mortgage loans occurs, the principal balance and certain payments owed to the holders of such GSE credit risk transfer securities may be reduced.

In the event that a government-sponsored enterprise fails to pay principal or interest on its credit risk transfer securities or goes through a bankruptcy, insolvency or similar proceeding, holders of such credit risk transfer securities have no direct recourse to the underlying mortgage loans and will generally receive recovery on par with other unsecured note holders in such a scenario. The risks associated with an investment in credit risk transfer securities are different than the risks associated with an investment in mortgage-backed securities issued by FNMA and FHLMC, or other government-sponsored enterprise or issued by a private issuer, because some or all of the mortgage default or credit risk associated with the underlying mortgage loans is transferred to investors. As a result, investors in these securities could lose some or all of their investment in these securities if the underlying mortgage loans default.

**Asset-backed securities**

The fund may invest in asset-backed securities. Asset-backed securities represent participations in, or are secured by and payable from, assets such as installment sales or loan contracts, leases, credit card receivables and other categories of receivables. The fund's investments in asset-backed securities may include derivative and structured securities.

The fund may invest in asset-backed securities issued by special entities, such as trusts, that are backed by a pool of financial assets. The fund may invest in collateralized debt obligations (CDOs), which include collateralized bond obligations (CBOs), collateralized loan obligations (CLOs) and other similarly structured securities. A CDO is a trust backed by a pool of fixed income securities. The trust typically is split into two or more portions, called tranches, which vary in credit quality, yield, credit support and right to repayment of principal and interest. Lower tranches pay higher interest rates but represent lower degrees of credit quality and are more sensitive to the rate of defaults in the pool of obligations. Certain CDOs may use derivatives, such as credit default swaps, to create synthetic exposure to assets rather than holding such assets directly.

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**Insurance-linked securities**

The fund may invest in insurance-linked securities (ILS). The fund could lose a portion or all of the principal it has invested in an ILS, and the right to additional interest or dividend payments with respect to the security, upon the occurrence of one or more trigger events, as defined within the terms of an insurance-linked security. Trigger events, generally, are hurricanes, earthquakes, or other natural events of a specific size or magnitude that occur in a designated geographic region during a specified time period, and/or that involve losses or other metrics that exceed a specific amount. There is no way to accurately predict whether a trigger event will occur, and accordingly, ILS carry significant risk. The fund is entitled to receive principal and interest and/or dividend payments so long as no trigger event occurs of the description and magnitude specified by the instrument. In addition to the specified trigger events, ILS may expose the fund to other risks, including but not limited to issuer (credit) default, adverse regulatory or jurisdictional interpretations and adverse tax consequences.

The fund's investments in ILS may include event-linked bonds. ILS also may include securities issued by special purpose vehicles ("SPVs") or similar instruments structured to comprise a portion of a reinsurer's catastrophe-oriented business, known as quota share instruments (sometimes referred to as reinsurance sidecars), or to provide reinsurance relating to specific risks to insurance or reinsurance companies through a collateralized instrument, known as collateralized reinsurance. Structured reinsurance investments also may include industry loss warranties ("ILWs"). A traditional ILW takes the form of a bilateral reinsurance contract, but there are also products that take the form of derivatives, collateralized structures, or exchange-traded instruments. The fund may invest in interests in pooled entities that invest primarily in ILS.

Where the ILS are based on the performance of underlying reinsurance contracts, the fund has limited transparency into the individual underlying contracts, and therefore must rely upon the risk assessment and sound underwriting practices of the insurer and/or reinsurer. Accordingly, it may be more difficult for Amundi US to fully evaluate the underlying risk profile of the fund's structured reinsurance investments, and therefore the fund's assets are placed at greater risk of loss than if Amundi US had more complete information. Structured reinsurance instruments generally will be considered illiquid securities by the fund.

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**Zero coupon securities**

The fund may invest in zero coupon securities. Zero coupon securities are debt instruments that do not pay interest during the life of the security but are issued at a discount from the amount the investor will receive when the issuer repays the amount borrowed (the face value). The discount approximates the total amount of interest that would be paid at an assumed interest rate.

**Repurchase agreements**

In a repurchase agreement, the fund purchases securities from a broker/dealer or a bank, called the counterparty, upon the agreement of the counterparty to repurchase the securities from the fund at a later date, and at a specified price, which is typically higher than the purchase price paid by the fund. The securities purchased serve as the fund's collateral for the obligation of the counterparty to repurchase the securities. If the counterparty does not repurchase the securities, the fund is entitled to sell the securities, but the fund may not be able to sell them for the price at which they were purchased, thus causing a loss. Additionally, if the counterparty becomes insolvent, there is some risk that the fund will not have a right to the securities, or the immediate right to sell the securities.

**Derivatives**

The fund may, but is not required to, use futures and options on securities, indices and currencies, forward foreign currency exchange contracts, swaps and other derivatives. The fund also may enter into credit default swaps, which can be used to acquire or to transfer the credit risk of a security or index of securities without buying or selling the security or securities comprising the relevant index. A derivative is a security or instrument whose value is determined by reference to the value or the change in value of one or more securities, currencies, indices or other financial instruments. The fund may use derivatives for a variety of purposes, including:

• In an attempt to hedge against adverse changes in the market prices of securities, interest rates or currency exchange rates

• As a substitute for purchasing or selling securities

• To attempt to increase the fund's return as a non-hedging strategy that may be considered speculative

• To manage portfolio characteristics (for example, the duration or credit quality of the fund's portfolio)

• As a cash flow management technique

The fund may choose not to make use of derivatives for a variety of reasons, and any use may be limited by applicable law and regulations.

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**Inverse floating rate obligations**

The fund may invest in inverse floating rate obligations (a type of derivative instrument). The interest rate on inverse floating rate obligations will generally decrease as short-term interest rates increase, and increase as short-term rates decrease. Due to their leveraged structure, the sensitivity of the market value of an inverse floating rate obligation to changes in interest rates is generally greater than a comparable long-term bond issued by the same issuer and with similar credit quality, redemption and maturity provisions. Inverse floating rate obligations may be volatile and involve leverage risk.

**Cash management and temporary investments**

Normally, the fund invests substantially all of its assets to meet its investment objective. The fund may invest the remainder of its assets in securities with remaining maturities of less than one year or cash equivalents, or may hold cash. For temporary defensive purposes, including during periods of unusual cash flows, the fund may depart from its principal investment strategies and invest part or all of its assets in these securities or may hold cash. The fund may adopt a defensive strategy when the adviser believes securities in which the fund normally invests have special or unusual risks or are less attractive due to adverse market, economic, political or other conditions. During such periods, it may be more difficult for the fund to achieve its investment objective.

**Additional investment strategies and related risks**

In addition to the principal investment strategies and related risks discussed in this prospectus, the fund may also use other techniques, including the following non-principal investment strategies and related risks.

**Reverse repurchase agreements and borrowing**

The fund may enter into reverse repurchase agreements pursuant to which the fund transfers securities to a counterparty in return for cash, and the fund agrees to repurchase the securities at a later date and for a higher price. Reverse repurchase agreements are treated as borrowings by the fund, are a form of leverage and may make the value of an investment in the fund more volatile and increase the risks of investing in the fund. The fund also may borrow money from banks or other lenders for temporary purposes. The fund may borrow up to 33 <sup>1</sup>∕3% of its total assets. Entering into reverse repurchase agreements and other borrowing transactions may cause the fund to liquidate positions when it may not be advantageous to do so in order to satisfy its obligations.

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**Short-term trading**

The fund usually does not trade for short-term profits. The fund will sell an investment, however, even if it has only been held for a short time, if it no longer meets the fund's investment criteria. If the fund does a lot of trading, it may incur additional operating expenses, which would reduce performance, and could cause shareowners to incur a higher level of taxable income or capital gains.

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**Principal investment risks**

You could lose money on your investment in the fund. As with any mutual fund, there is no guarantee that the fund will achieve its objective.

**Market risk.** The market prices of securities or other assets held by the fund may go up or down, sometimes rapidly or unpredictably, due to general market conditions, such as real or perceived adverse economic, political, or regulatory conditions, political instability, recessions, inflation, changes in interest or currency rates, lack of liquidity in the bond markets, the spread of infectious illness or other public health issues, armed conflict, market disruptions caused by tariffs, trade disputes, sanctions or other government actions, or other factors or adverse investor sentiment. If the market prices of the fund's securities and assets fall, the value of your investment will go down. A change in financial condition or other event affecting a single issuer or market may adversely impact securities markets as a whole.

Changes in market conditions may not have the same impact on all types of securities. The value of securities may also fall due to specific conditions that affect a particular sector of the securities market or a particular issuer. In the past decade, financial markets throughout the world have experienced increased volatility, depressed valuations, decreased liquidity and heightened uncertainty. Governmental and non-governmental issuers have defaulted on, or been forced to restructure, their debts. These conditions may continue, recur, worsen or spread. Events that have contributed to these market conditions include, but are not limited to, major cybersecurity events; geopolitical events (including wars, terror attacks and economic sanctions); measures to address budget deficits; downgrading of sovereign debt; changes in oil and commodity prices; dramatic changes in currency exchange rates; global pandemics; and public sentiment. The fallout from the COVID-19 pandemic and subsequent variants of COVID-19, and the long-term impact on economies, markets, industries and individual issuers, are not known. Some sectors of the economy and individual issuers have experienced or may experience particularly large losses. Periods of extreme volatility in the financial markets; reduced liquidity of many instruments; and disruptions to supply chains, consumer demand and employee availability, may continue for some time.

Raising the ceiling on U.S. government debt has become increasingly politicized. Any failure to increase the ceiling on U.S. government debt could lead to a default on U.S. government obligations, with unpredictable consequences for economies and markets in the U.S. and elsewhere. Recently, inflation and interest rates have increased and may rise further. These circumstances could adversely affect the value and liquidity of the fund's investments, impair the fund's ability to satisfy redemption requests, and negatively impact the fund's performance. Following

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Russia's invasion of Ukraine, Russian securities have lost all, or nearly all, their market value. Other securities or markets could be similarly affected by past or future political, geopolitical or other events or conditions.

Governments and central banks, including the U.S. Federal Reserve, have taken extraordinary and unprecedented actions to support local and global economies and the financial markets. These actions have resulted in significant expansion of public debt, including in the U.S. The consequences of high public debt, including its future impact on the economy and securities markets, may not be known for some time. U.S. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including increases or decreases in interest rates, or contrary actions by different governments, could negatively affect financial markets generally, increase market volatility and reduce the value and liquidity of securities in which the fund invests. Policy and legislative changes in the U.S. and in other countries are affecting many aspects of financial regulation, and these and other events affecting global markets, such as the United Kingdom's exit from the European Union (or Brexit), potential trade imbalances with China or other countries, or sanctions or other government actions against Russia, other nations or individuals or companies (or their countermeasures), may contribute to decreased liquidity and increased volatility in the financial markets. The impact of these changes on the markets, and the implications for market participants, may not be fully known for some time.

The United States and other countries are periodically involved in disputes over trade and other matters, which may result in tariffs, investment restrictions and adverse impacts on affected companies and securities. For example, the United States has imposed tariffs and other trade barriers on Chinese exports, has restricted sales of certain categories of goods to China, and has established barriers to investments in China. Trade disputes may adversely affect the economies of the United States and its trading partners, as well as companies directly or indirectly affected and financial markets generally. The United States government has prohibited U.S. persons, such as the fund, from investing in Chinese companies designated as related to the Chinese military. These and possible future restrictions could limit the fund's opportunities for investment and require the sale of securities at a loss or make them illiquid. Moreover, the Chinese government is involved in a longstanding dispute with Taiwan that has included threats of invasion. If the political climate between the United States and China does not improve or continues to deteriorate, if China were to attempt unification of Taiwan by force, or if other geopolitical conflicts develop or get worse, economies, markets and individual securities may be severely affected both regionally and globally, and the value of the fund's assets may go down.

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Economies and financial markets throughout the world are increasingly interconnected. Economic, financial or political events, trading and tariff arrangements, armed conflict including Russia's military invasion of Ukraine, terrorism, natural disasters, infectious illness or public health issues, cybersecurity events, supply chain disruptions, sanctions against Russia, other nations or individuals or companies and possible countermeasures, and other circumstances in one country or region, could have profound impacts on other countries or regions and on global economies or markets. As a result, whether or not the fund invests in securities of issuers located in or with significant exposure to the countries or regions directly affected, the value and liquidity of the fund's investments may be negatively affected. The fund may experience a substantial or complete loss on any security or derivative position.

LIBOR (London Interbank Offered Rate) is used extensively in the U.S. and globally as a "benchmark" or "reference rate" for various commercial and financial contracts, including corporate and municipal bonds, bank loans, asset-backed and mortgage-related securities, and interest rate swaps and other derivatives. ICE Benchmark Administration, the administrator of LIBOR, ceased publication of most LIBOR settings on a representative basis at the end of 2021 and is expected to cease publication of a majority of U.S. dollar LIBOR settings on a representative basis after June 30, 2023. In addition, global regulators have announced that, with limited exceptions, no new LIBOR-based contracts should be entered into after 2021. Actions by regulators have resulted in the establishment of alternative reference rates to LIBOR in most major currencies. Markets are developing in response to these new rates, but questions around liquidity in these rates and how to appropriately adjust these rates to eliminate any economic value transfer at the time of transition remain a significant concern. The effect of any changes to—or discontinuation of—LIBOR on the fund will vary depending on, among other things, existing fallback provisions in individual contracts and whether, how, and when industry participants develop and widely adopt new reference rates and fallbacks for both legacy and new products and instruments. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that rely on LIBOR. The transition may also result in a reduction in the value of certain LIBOR-based investments held by the fund or reduce the effectiveness of related transactions such as hedges. Any such effects of the transition away from LIBOR as well as other unforeseen effects, could result in losses for the fund. Because the usefulness of LIBOR as a benchmark may deteriorate during the transition period, these effects could occur at any time.

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**High yield or "junk" bond risk.** Debt securities that are below investment grade, called "junk bonds," are speculative, have a higher risk of default or are already in default, tend to be less liquid and are more difficult to value than higher grade securities and may involve major risk of exposure to adverse conditions and negative sentiments. These securities have a higher risk of issuer default because, among other reasons, issuers of junk bonds often have more debt in relation to total capitalization than issuers of investment grade securities. Junk bonds tend to be volatile and more susceptible to adverse events and negative sentiments. These risks are more pronounced for securities that are already in default. The fund may not receive interest payments on defaulted securities and may incur costs to protect its investment. In addition, defaulted securities involve the substantial risk that principal will not be repaid. Changes in economic conditions or developments regarding the individual issuer are more likely to cause price volatility and weaken the capacity of such securities to make principal and interest payments than is the case for higher grade debt securities. The value of lower-quality debt securities often changes in response to company, political, or economic developments and can decline significantly over short as well as long periods of time or during periods of general or regional economic difficulty. Junk bonds may also be less liquid than higher-rated securities, which means that the fund may have difficulty selling them at times, and it may have to apply a greater degree of judgment in establishing a price for purposes of valuing fund shares. Junk bonds generally are issued by less creditworthy issuers. Issuers of junk bonds may have a larger amount of outstanding debt securities relative to their assets than issuers of investment grade bonds. In the event of an issuer's bankruptcy, claims of other creditors may have priority over the claims of junk bond holders, leaving few or no assets available to repay junk bond holders. The fund may incur expenses to the extent necessary to seek recovery upon default or to negotiate new terms with a defaulting issuer. Junk bonds frequently have redemption features that permit an issuer to repurchase the security from the fund before it matures. If the issuer redeems junk bonds, the fund may have to invest the proceeds in bonds with lower yields and may lose income.

**Interest rate risk.** The market prices of the fund's fixed income securities may fluctuate significantly when interest rates change. When interest rates rise, the value of fixed income securities and therefore the value of your investment in the fund, generally falls. For example, if interest rates increase by 1%, the value of a fund's portfolio with a portfolio duration of ten years would be expected to decrease by 10%, all other things being equal.

In recent years, interest rates and credit spreads in the U.S. have been at historic lows. The U.S. Federal Reserve has raised certain interest rates, and interest rates may continue to go up. A general rise in interest rates could adversely affect the

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price and liquidity of fixed income securities and could also result in increased redemptions from the fund. A change in interest rates will not have the same impact on all fixed income securities. Generally, the longer the maturity or duration of a fixed income security, the greater the impact of a rise in interest rates on the security's value. The maturity of a security may be significantly longer than its effective duration. A security's maturity and other features may be more relevant than its effective duration in determining the security's sensitivity to other factors affecting the issuer or markets generally, such as changes in credit quality or in the yield premium that the market may establish for certain types of securities (sometimes called "credit spread"). In general, the longer its maturity the more a security may be susceptible to these factors. When the credit spread for a fixed income security goes up or "widens," the value of the security will generally go down. Calculations of duration and maturity may be based on estimates and may not reliably predict a security's price sensitivity to changes in interest rates. Moreover, securities can change in value in response to other factors, such as credit risk. In addition, different interest rate measures (such as short- and long-term interest rates and U.S. and foreign interest rates), or interest rates on different types of securities or securities of different issuers, may not necessarily change in the same amount or in the same direction. When interest rates go down, the income received by the fund, and the fund's yield, may decline. Also, when interest rates decline, investments made by the fund may pay a lower interest rate, which would reduce the income received and distributed by the fund.

Certain fixed income securities pay interest at variable or floating rates. Variable rate securities tend to reset at specified intervals, while floating rate securities may reset whenever there is a change in a specified index rate. In most cases, these reset provisions reduce the impact of changes in market interest rates on the value of the security. However, some securities do not track the underlying index directly, but reset based on formulas that may produce a leveraging effect; others may also provide for interest payments that vary inversely with market rates. The market prices of these securities may fluctuate significantly when interest rates change. Yield generated by the fund may decline due to a decrease in market interest rates.

The values of securities with floating interest rates generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as prevailing interest rates. In addition, rising interest rates can also lead to increased default rates, as issuers of floating rate securities find themselves faced with higher payments. Further, in the case of some instruments, if the underlying reference interest rate does not move by at least a prescribed increment, no adjustment will occur in the floating rate instrument's interest rate. This means that, when prevailing interest rates increase, a corresponding increase

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in the instrument's interest rate may not result and the instrument may decline in value. Similarly, certain floating rate obligations have an interest rate floor feature, which prevents the interest rate payable by the security from dropping below a specified level as compared to a reference interest rate. Such a floor protects the fund from losses resulting from a decrease in the reference interest rate below the specified level. However, if the reference interest rate is below the floor, there will be a lag between a rise in the reference interest rate and a rise in the interest rate payable by the obligation, and the fund may not benefit from increasing interest rates for a significant amount of time. Unlike fixed rate securities, floating rate securities generally will not increase in value if interest rates decline. Changes in interest rates also will affect the amount of interest income the fund earns on its floating rate investments. Unlike fixed rate securities, when prevailing interest rates decrease, the interest rate payable on floating rate investments will decrease.

The interest rates of some floating rate obligations adjust only periodically. Between the times that interest rates on floating rate obligations adjust, the interest rate on those obligations may not correlate to prevailing rates, which will affect the value of the loans and may cause the net asset values of the fund's shares to fluctuate.

**Credit risk.** If an obligor (such as the issuer itself or a party offering credit enhancement) for a security held by the fund fails to pay, otherwise defaults, is perceived to be less creditworthy, becomes insolvent or files for bankruptcy, a security's credit rating is downgraded or the credit quality or value of an underlying asset declines, the value of your investment could decline. Changes in actual or perceived creditworthiness may occur quickly. If the fund enters into financial contracts (such as certain derivatives, repurchase agreements, reverse repurchase agreements, and when-issued, delayed delivery and forward commitment transactions), the fund will be subject to the credit risk presented by the counterparty. In addition, the fund may incur expenses and suffer delays in an effort to protect the fund's interests or to enforce its rights. A security may change in price for a variety of reasons. For example, floating rate securities may have final maturities of ten or more years, but their effective durations will tend to be very short. If there is an adverse credit event, or a perceived change in the issuer's creditworthiness, these securities could experience a far greater negative price movement than would be predicted by the change in the security's yield in relation to their effective duration. The fund evaluates the credit quality of issuers and counterparties prior to investing in securities. Credit risk is broadly gauged by the credit ratings of the securities in which the fund invests. However, ratings are only the opinions of the companies issuing them and are not guarantees as to quality. Securities rated in the lowest category of investment grade (Baa/BBB) may possess certain speculative characteristics.

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**Prepayment or call risk.** Many fixed income securities give the issuer the option to prepay or call the security prior to its maturity date. Issuers often exercise this right when interest rates fall. Accordingly, if the fund holds a fixed income security that can be prepaid or called prior to its maturity date, it will not benefit fully from the increase in value that other fixed income securities generally experience when interest rates fall. Upon prepayment of the security, the fund also would be forced to reinvest the proceeds at then current yields, which would be lower than the yield of the security that was prepaid or called. In addition, if the fund purchases a fixed income security at a premium (at a price that exceeds its stated par or principal value), the fund may lose the amount of the premium paid in the event of prepayment.

**Extension risk.** During periods of rising interest rates, the average life of certain types of securities may be extended because of slower than expected principal payments. This may lock in a below market interest rate, increase the security's duration and reduce the value of the security.

To the extent the fund invests significantly in mortgage-related and asset-backed securities, its exposure to extension risks may be greater than if it invested in other fixed income securities.

**Liquidity risk.** Liquidity risk is the risk that particular investments, or investments generally, may be or become impossible or difficult to purchase or sell. Although most of the fund's securities and other investments must be liquid at the time of investment, securities and other investments may become illiquid after purchase by the fund, particularly during periods of market turmoil or due to adverse changes in the conditions of a particular issuer. Liquidity and value of investments can deteriorate rapidly. Markets may become illiquid when, for instance, there are few, if any, interested buyers and sellers or when dealers are unwilling to make a market for certain securities or when dealer market-making capacity is otherwise reduced. During times of market turmoil, there have been, and may be, no buyers for securities in entire asset classes, including U.S. Treasury securities. A lack of liquidity or other adverse credit market conditions may affect the fund's ability to sell the securities in which it invests or to find and purchase suitable investments. When the fund holds illiquid investments, the fund may be harder to value, especially in changing markets. If the fund is forced to sell or unwind an illiquid investment to meet redemption requests or for other cash needs, or to try to limit losses, the fund may suffer a substantial loss or may not be able to sell at all. The fund may experience heavy redemptions that could cause the fund to liquidate its assets at inopportune times or at a loss or depressed value, which could cause the value of your investment to decline. In addition, when there is illiquidity in the market for certain securities and other investments, the fund, due to limitations on investments in illiquid

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securities, may be unable to achieve its desired level of exposure to a certain sector. Further, certain securities, once sold, may not settle for an extended period (for example, several weeks or even longer). The fund will not receive its sales proceeds until that time, which may constrain the fund's ability to meet its obligations (including obligations to redeeming shareholders). Liquidity risk may be magnified in an environment of rising interest rates or widening credit spreads in which investor redemptions from fixed income mutual funds may be higher than normal. If an auction fails for an auction rate security, there may be no secondary market for the security and the fund may be forced to hold the security until the security is refinanced by the issuer or a secondary market develops. To the extent the fund holds a material percentage of the outstanding debt securities of an issuer, this practice may impact adversely the liquidity and market value of those investments.

**Portfolio selection risk.** The adviser's judgment about the quality, relative yield, relative value or market trends affecting a particular sector or region, market segment, security, industry or about interest rates or other market factors may prove to be incorrect or may not produce the desired results, or there may be imperfections, errors or limitations in the models, tools and information used by the adviser.

**ESG risk.** The fund's adviser may consider ESG information in its investment research process. This may mean forgoing some investment opportunities available to funds that do not consider ESG information. In considering ESG information, the adviser may use third party ESG ratings information that it believes to be reliable, but such information may not be accurate or complete, or may be biased. ESG considerations are not a primary focus of the fund, and the weight given by the adviser to ESG considerations in making investment decisions will vary and, for any specific decision, they may be given little or no weight.

**Risks of investing in loans**. Floating rate loans and similar investments may be illiquid or less liquid than other investments and difficult to value. Market quotations for these securities may be volatile and/or subject to large spreads between bid and ask prices. No active trading market may exist for many floating rate loans, and many loans are subject to restrictions on resale. Any secondary market may be subject to irregular trading activity and extended trade settlement periods. An economic downturn generally leads to a higher non-payment rate, and a loan may lose significant value before a default occurs.

When the fund invests in a loan participation, the fund does not have a direct claim against the borrower and must rely upon an intermediate participant to enforce any rights against the borrower. As a result, the fund is subject to the risk that an intermediate participant between the fund and the borrower will fail to

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meet its obligations to the fund, in addition to the risk that the issuer of the loan will default on its obligations. Also the fund may be regarded as the creditor of the agent lender (rather than the borrower), subjecting the fund to the creditworthiness of the lender as well as the borrower.

There is less readily available, reliable information about most senior loans than is the case for many other types of securities. Although the features of senior loans, including being secured by collateral and having priority over other obligations of the issuer, reduce some of the risks of investment in below investment grade securities, the loans are subject to significant risks. Amundi US believes, based on its experience, that senior floating rate loans generally have more favorable loss recovery rates than most other types of below investment grade obligations. However, there can be no assurance that the fund's actual loss recovery experience will be consistent with Amundi US's prior experience or that the senior loans in which the fund invests will achieve any specific loss recovery rate.

Loans may take longer than seven days to settle, potentially leading to the sale proceeds of loans not being available to meet redemption requests for a substantial period of time after the sale of the loans. To the extent that sale proceeds of loans are not available, the fund may sell securities that have shorter settlement periods or may access other sources of liquidity to meet redemption requests. During periods of heightened redemption activity or distressed market conditions, the fund may seek to obtain expedited trade settlement, which will generally incur additional costs (although expedited trade settlement will not always be available).

The types of covenants included in loan agreements generally vary depending on market conditions, the creditworthiness of the issuer, the nature of the collateral securing the loan, and other factors. Loans may have restrictive covenants that limit the ability of a borrower to further encumber its assets. If a borrower fails to comply with the covenants included in a loan agreement, the borrower may default in payment of the loan.

Some of the loans in which the fund may invest may be "covenant lite." Covenant lite loans contain fewer maintenance covenants, or no maintenance covenants at all, than traditional loans and may not include terms that allow the lender to monitor the financial performance of the borrower and declare a default if certain criteria are breached. This may expose the fund to greater credit risk associated with the borrower and reduce the fund's ability to restructure a problematic loan and mitigate potential loss. As a result the fund's exposure to losses on such investments may be increased, especially during a downturn in the credit cycle.

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Second lien loans generally are subject to similar risks as those associated with senior loans. Because second lien loans are subordinated or unsecured and thus lower in priority on payment to senior loans, they are subject to the additional risk that the cash flow of the borrower and property securing the loan or debt, if any, may be insufficient to meet scheduled payments after giving effect to the senior secured obligations of the borrower. This risk is generally higher for subordinated unsecured loans or debt, which are not backed by a security interest in any specific collateral. Second lien loans generally have greater price volatility than senior loans and may be less liquid.

Certain floating rate loans and other corporate debt securities involve refinancings, recapitalizations, mergers and acquisitions, and other financings for general corporate purposes. Other loans are incurred in restructuring or "work-out" scenarios, including debtor-in-possession facilities in bankruptcy. Loans in restructuring or similar scenarios may be especially vulnerable to the inherent uncertainties in restructuring processes. In addition, the highly leveraged capital structure of the borrowers in any of these transactions, whether acquisition financing or restructuring, may make the loans especially vulnerable to adverse economic or market conditions and the risk of default.

Loans to entities located outside of the U.S. may have substantially different lender protections and covenants as compared to loans to U.S. entities and may involve greater risks. The fund may have difficulties and incur expense enforcing its rights with respect to non-U.S. loans and such loans could be subject to bankruptcy laws that are materially different than in the U.S.

Because affiliates of Amundi US may participate in the primary and secondary market for senior loans, limitations under applicable law may restrict the fund's ability to participate in structuring a senior loan or to acquire some senior loans, or affect the timing or price of such acquisition.

Loans may not be considered "securities," and purchasers, such as the fund, therefore may not be entitled to rely on the anti-fraud protections afforded by federal securities laws.

**Collateral risk.** The value of collateral, if any, securing a floating rate loan can decline, and may be insufficient to meet the issuer's obligations or may be difficult to liquidate. In addition, the fund's access to collateral may be limited by bankruptcy or other insolvency laws. These laws may be less developed and more cumbersome with respect to the fund's non-U.S. floating rate investments. Floating rate loans may not be fully collateralized or may be uncollateralized. Uncollateralized loans involve a greater risk of loss. In the event of a default, the fund may have difficulty

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collecting on any collateral and would not have the ability to collect on any collateral for an uncollateralized loan. In addition, the lender's security interest or their enforcement of their security interest under the loan agreement may be found by a court to be invalid or the collateral may be used to pay other outstanding obligations of the borrower. Further, the fund's access to collateral, if any, may be limited by bankruptcy law. To the extent that a loan is collateralized by stock of the borrower or its affiliates, this stock may lose all or substantially all of its value in the event of bankruptcy of the borrower. Loans that are obligations of a holding company are subject to the risk that, in a bankruptcy of a subsidiary operating company, creditors of the subsidiary may recover from the subsidiary's assets before the lenders to the holding company would receive any amount on account of the holding company's interest in the subsidiary.

**Risk of disadvantaged access to confidential information.** The issuer of a floating rate loan may offer to provide material, non-public information about the issuer to investors, such as the fund. Normally, Amundi US will seek to avoid receiving this type of information about the issuer of a loan either held by, or considered for investment by, the fund. Amundi US's decision not to receive the information may place it at a disadvantage, relative to other loan investors, in assessing a loan or the loan's issuer. For example, in instances where holders of floating rate loans are asked to grant amendments, waivers or consents, Amundi US's inability to assess the impact of these actions may adversely affect the value of the portfolio. For this and other reasons, it is possible that Amundi US's decision not to receive material, non-public information under normal circumstances could adversely affect the fund's investment performance.

**Risks of subordinated securities.** A holder of securities that are subordinated or "junior" to more senior securities of an issuer is entitled to payment after holders of more senior securities of the issuer. Subordinated securities are more likely to suffer a credit loss than non-subordinated securities of the same issuer, any loss incurred by the subordinated securities is likely to be proportionately greater, and any recovery of interest or principal may take more time. If there is a default, bankruptcy or liquidation of the issuer, most subordinated securities are paid only if sufficient assets remain after payment of the issuer's non-subordinated securities. As a result, even a perceived decline in creditworthiness of the issuer is likely to have a greater impact on subordinated securities than more senior securities.

**U.S. Treasury obligations risk.** The market value of direct obligations of the U.S. Treasury may vary due to changes in interest rates. In addition, changes to the financial condition or credit rating of the U.S. government may cause the value of the fund's investments in obligations issued by the U.S. Treasury to decline.

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**U.S. government agency obligations risk.** The fund invests in obligations issued by agencies and instrumentalities of the U.S. government. Government-sponsored entities such as FNMA, FHLMC and the FHLBs, although chartered or sponsored by Congress, are not funded by congressional appropriations and the debt and mortgage-backed securities issued by them are neither guaranteed nor issued by the U.S. government. The maximum potential liability of the issuers of some U.S. government obligations may greatly exceed their current resources, including any legal right to support from the U.S. government. Such debt and mortgage-backed securities are subject to the risk of default on the payment of interest and/or principal, similar to debt of private issuers. Although the U.S. government has provided financial support to FNMA and FHLMC in the past, there can be no assurance that it will support these or other government-sponsored entities in the future.

**Mortgage-related and asset-backed securities risk.** The repayment of certain mortgage-backed and asset-backed securities depends primarily on the cash collections received from the issuer's underlying asset portfolio and, in certain cases, the issuer's ability to issue replacement securities. As a result, there could be losses to the fund in the event of credit or market value deterioration in the issuer's underlying portfolio, mismatches in the timing of the cash flows of the underlying asset interests and the repayment obligations of maturing securities, or the issuer's inability to issue new or replacement securities. Mortgage-backed securities tend to be more sensitive to changes in interest rates than other types of debt securities. These securities are also subject to interest rate, prepayment and extension risks. Upon the occurrence of certain triggering events or defaults, the investors in a security held by the fund may become the holders of underlying assets at a time when those assets may be difficult to sell or may be sold only at a loss. In the event of a default, the value of the underlying collateral may be insufficient to pay certain expenses, such as litigation and foreclosure expenses, and inadequate to pay any principal or unpaid interest. The risk of default is generally higher in the case of mortgage-backed investments offered by private issuers and those that include so-called "sub-prime" mortgages. Privately issued mortgage-backed and asset-backed securities are not traded on an exchange and may have a limited market. Without an active trading market, these securities may be particularly difficult to value given the complexities in valuing the underlying collateral.

Certain mortgage-backed and asset-backed securities may pay principal only at maturity or may represent only the right to receive payments of principal or interest on the underlying obligations, but not both. The value of these types of instruments may change more than the value of debt securities that pay both principal and interest during periods of changing interest rates. Principal only instruments

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generally increase in value if interest rates decline, but are also subject to the risk of prepayment. Interest only instruments generally increase in value in a rising interest rate environment when fewer of the underlying obligations are prepaid. Interest only instruments could lose their entire value in a declining interest rate environment if the underlying obligations are prepaid.

Unlike mortgage-related securities issued or guaranteed by the U.S. government or its agencies and instrumentalities, mortgage-related securities issued by private issuers do not have a government or government-sponsored entity guarantee (but may have other credit enhancement), and may, and frequently do, have less favorable collateral, credit risk or other characteristics. The fund may invest in other mortgage-related securities, including mortgage derivatives and structured securities. These securities typically are not secured by real property. Because these securities have embedded leverage features, small changes in interest or prepayment rates may cause large and sudden price movements. These securities also can become illiquid and difficult to value in volatile or declining markets. Privately issued mortgage-related securities are also not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the fund's portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.

Mortgage-backed securities are particularly susceptible to prepayment and extension risks, because prepayments on the underlying mortgages tend to increase when interest rates fall and decrease when interest rates rise. Prepayments may also occur on a scheduled basis or due to foreclosure. When market interest rates increase, mortgage refinancings and prepayments slow, which lengthens the effective duration of these securities. As a result, the negative effect of the interest rate increase on the market value of mortgage-backed securities is usually more pronounced than it is for other types of fixed income securities, potentially increasing the volatility of the fund. Conversely, when market interest rates decline, while the value of mortgage-backed securities may increase, the rates of prepayment of the underlying mortgages tend to increase, which shortens the effective duration of these securities. Mortgage-backed securities are also subject to the risk that the underlying borrowers will be unable to meet their obligations.

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At times, some of the mortgage-backed securities in which the fund may invest will have higher than market interest rates and therefore will be purchased at a premium above their par value. Prepayments may cause losses on securities purchased at a premium.

The value of mortgage-backed and asset-backed securities may be affected by changes in credit quality or value of the mortgage loans or other assets that support the securities. In addition, for mortgage-backed securities, when market conditions result in an increase in the default rates on the underlying mortgages and the foreclosure values of the underlying real estate are below the outstanding amount of the underlying mortgages, collection of the full amount of accrued interest and principal on these investments may be less likely.

The fund may invest in CMOs. Principal prepayments on the underlying mortgage loans may cause a CMO to be retired substantially earlier than its stated maturity or final distribution date. If there are defaults on the underlying mortgage loans, the fund will be less likely to receive payments of principal and interest, and will be more likely to suffer a loss. This risk may be increased to the extent the underlying mortgages include sub-prime mortgages. As market conditions change, and particularly during periods of rapid or unanticipated changes in market interest rates, the attractiveness of a CMO class and the ability of the structure to provide the anticipated investment characteristics may be significantly reduced. Such changes can result in volatility in the market value, and in some instances reduced liquidity, of a CMO class.

The fund may invest in credit risk transfer ("CRT") securities. CRT securities are unguaranteed and unsecured fixed income securities issued by government-sponsored or private entities that transfer the credit risk related to certain types of mortgage-backed securities to the holder of the CRT security. In the event of an issuer default, the holder of a CRT security has no direct recourse to the underlying mortgage loans. In addition, if the underlying mortgage loans default, the principal of the holders of the CRT security is used to pay back holders of the mortgage-backed securities. As a result, all or part of the mortgage default or credit risk associated with the underlying mortgage loans is transferred to the fund. Therefore, the fund could lose all or part of its investments in credit risk transfer securities in the event of default by the underlying mortgage loans.

The fund may invest in commercial mortgage-backed securities ("CMBS"). CMBS are subject to the risks generally associated with mortgage-backed securities. CMBS may not be backed by the full faith and credit of the U.S. government and are subject to risk of default on the underlying mortgages. CMBS issued by non-government entities may offer higher yields than those issued by government

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entities, but also may be subject to greater volatility than government issues. CMBS react differently to changes in interest rates than other bonds and the prices of CMBS may reflect adverse economic and market conditions. Small movements in interest rates (both increases and decreases) may quickly and significantly reduce the value of CMBS.

Asset-backed securities are structured like mortgage-backed securities and are subject to many of the same risks. The ability of an issuer of asset-backed securities to enforce its security interest in the underlying assets or to otherwise recover from the underlying obligor may be limited. Certain asset-backed securities present a heightened level of risk because, in the event of default, the liquidation value of the underlying assets may be inadequate to pay any unpaid principal or interest.

**Risks of investing in collateralized debt obligations.** Investment in a collateralized debt obligation (CDO) is subject to the credit, subordination, interest rate, valuation, prepayment, extension and other risks of the obligations underlying the CDO and the tranche of the CDO in which the fund invests. CDOs are subject to liquidity risk. CDOs carry additional risks including, but not limited to: (i) the possibility that distributions from collateral securities will not be adequate to make interest or other payments; (ii) the risk that the collateral may default or decline in value or be downgraded, if rated by a nationally recognized statistical rating organization; (iii) the fund may invest in tranches of CDOs that are subordinate to other tranches; (iv) the structure and complexity of the transaction and the legal documents could lead to disputes among investors regarding the characterization of proceeds; (v) the investment return achieved by the fund could be significantly different than those predicted by financial models; (vi) the lack of a readily available secondary market for CDOs; (vii) the risk of forced "fire sale" liquidation due to technical defaults such as coverage test failures; and (viii) the CDO's manager may perform poorly. In addition, investments in CDOs may be characterized by the fund as illiquid securities. CDOs may be highly leveraged (which could make them highly volatile). Synthetic CDOs are also subject to the risks of investing in derivatives, such as credit default swaps, and leverage risk. The fund may invest in or be exposed to CDOs that are sometimes referred to as "covenant-lite" obligations, which generally are debt obligations that lack financial maintenance covenants or possess fewer or contingent financial maintenance covenants and other financial protections for lenders and investors. These "covenant-lite" obligations typically are particularly subject to the risks associated with investments in loans as described in this prospectus.

**Risks of instruments that allow for balloon payments or negative amortization payments.** Certain debt instruments allow for balloon payments or negative amortization payments. Such instruments permit the borrower to

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avoid paying currently a portion of the interest accruing on the instrument. While these features make the debt instrument more affordable to the borrower in the near term, they increase the risk that the borrower will be unable to make the resulting higher payment or payments that become due at the maturity of the loan.

**Risks of investing in insurance-linked securities.** The fund could lose a portion or all of the principal it has invested in an insurance-linked security, and the right to additional interest and/or dividend payments with respect to the security, upon the occurrence of one or more trigger events, as defined within the terms of an insurance-linked security. Trigger events may include natural or other perils of a specific size or magnitude that occur in a designated geographic region during a specified time period, and/or that involve losses or other metrics that exceed a specific amount. Natural perils include disasters such as hurricanes, earthquakes, windstorms, fires, floods and other weather-related occurrences, as well as mortality or longevity events. Non-natural perils include disasters resulting from human-related activity such as commercial and industrial accidents or business interruptions. Major natural disasters (such as in the cases of Super Typhoon Goni in the Philippines in 2020, monsoon flooding in China in 2020, Hurricane Irma in Florida and the Caribbean in 2017, Super Storm Sandy in 2012, and Hurricane Ian in Florida in 2022) or commercial and industrial accidents (such as aviation disasters and oil spills) can result in significant losses, and investors in ILS with exposure to such natural or other disasters may also experience substantial losses. If the likelihood and severity of natural and other large disasters increase, the risk of significant losses to reinsurers may increase. Typically, one significant triggering event (even in a major metropolitan area) will not result in financial failure to a reinsurer. However, a series of major triggering events could cause the failure of a reinsurer. Similarly, to the extent the fund invests in ILS for which a triggering event occurs, losses associated with such event will result in losses to the fund and a series of major triggering events affecting a large portion of the ILS held by the fund will result in substantial losses to the fund. The fund may also invest in insurance-linked securities that are subject to "indemnity triggers." An indemnity trigger is a trigger based on the actual losses of the ceding sponsor (i.e., the party seeking reinsurance). Insurance-linked securities subject to indemnity triggers are often regarded as being subject to potential moral hazard, since such insurance-linked securities are triggered by actual losses of the ceding sponsor and the ceding sponsor may have an incentive to take actions and/or risks that would have an adverse effect on the fund. For example, a ceding sponsor might inflate its total claims paid above the ILS trigger level, in order to share its losses with investors in the ILS. Thus, bonds with indemnity triggers may be subject to moral hazard, because the trigger depends on the ceding sponsor to properly identify and calculate losses that do and do not

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apply in determining whether the trigger amount has been reached. In short, "moral hazard" refers to this potential for the sponsor to influence bond performance, as payouts are based on the individual policy claims against the sponsor and the way the sponsor settles those claims. There is no way to accurately predict whether a trigger event will occur and, accordingly, insurance-linked securities carry significant risk. In addition to the specified trigger events, insurance-linked securities may expose the fund to other risks, including but not limited to issuer (credit) default, adverse regulatory or jurisdictional interpretations and adverse tax consequences. Insurance-linked securities are also subject to the risk that the model used to calculate the probability of a trigger event was not accurate and underestimated the likelihood of a trigger event. Insurance-linked securities may provide for extensions of maturity in order to process and audit loss claims in those cases when a trigger event has, or possibly has, occurred. Certain insurance-linked securities may have limited liquidity, or may be illiquid. Upon the occurrence or possible occurrence of a trigger event, and until the completion of the processing and auditing of applicable loss claims, the fund's investment in an insurance-linked security may be priced using fair value methods. Lack of a liquid market may impose the risk of higher transaction costs and the possibility that the fund may be forced to liquidate positions when it would not be advantageous to do so. Certain insurance-linked securities represent interests in baskets of underlying reinsurance contracts. The fund has limited transparency into the individual contracts underlying such securities and therefore must rely on the risk assessment and sound underwriting practices of the insurer and/or reinsurer. Certain insurance-linked securities may be difficult to value.

**Risks of zero coupon bonds, payment in kind, deferred and contingent payment securities.** Zero coupon bonds (which do not pay interest until maturity) and payment in kind securities (which pay interest in the form of additional securities) may be more speculative and may fluctuate more in value than securities which pay income periodically and in cash. Payment in kind securities are usually less volatile than zero coupon bonds, but more volatile than cash pay securities. These securities are more likely to respond to changes in interest rates than interest-bearing securities having similar maturities and credit quality. The higher interest rates of payment in kind securities reflect the payment deferral and increased credit risk associated with these instruments, and payment in kind instruments generally represent a significantly higher credit risk than coupon bonds. These securities are more sensitive to the credit quality of the underlying issuer. Payment in kind securities may be difficult to value because their continuing accruals require continuing judgments about the collectability of the deferred payments and the value of any associated collateral. Deferred interest securities are obligations that

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generally provide for a period of delay before the regular payment of interest begins and are issued at a significant discount from face value. The interest rate on contingent payment securities is determined by the outcome of an event, such as the performance of a financial index. If the financial index does not increase by a prescribed amount, the fund may receive no interest.

Unlike bonds that pay interest throughout the period to maturity, the fund generally will realize no cash until maturity and, if the issuer defaults, the fund may obtain no return at all on its investment. In addition, although the fund receives no periodic cash payments on such securities, the fund is deemed for tax purposes to receive income from such securities, which applicable tax rules require the fund to distribute to shareholders. Such distributions may be taxable when distributed to shareholders and, in addition, could reduce the fund's reserve position and require the fund to sell securities and incur a gain or loss at a time it may not otherwise want in order to provide the cash necessary for these distributions.

**Risks of non-U.S. investments.** Investing in non-U.S. issuers, or in U.S. issuers that have significant exposure to foreign markets, may involve unique risks compared to investing in securities of U.S. issuers. These risks are more pronounced for issuers in emerging markets or to the extent that the fund invests significantly in one region or country. These risks may include:

• Less information about non-U.S. issuers or markets may be available due to less rigorous disclosure or accounting standards or regulatory practices

• Many non-U.S. markets are smaller, less liquid and more volatile. In a changing market, the adviser may not be able to sell the fund's securities at times, in amounts and at prices it considers reasonable

• Adverse effect of currency exchange rates or controls on the value of the fund's investments, or its ability to convert non-U.S. currencies to U.S. dollars

• The economies of non-U.S. countries may grow at slower rates than expected or may experience a downturn or recession

• Economic, political, regulatory and social developments, military conflicts and sanctions, nationalization or expropriation of assets, arbitrary application of laws and regulations or lack of rule of law, may adversely affect the securities markets

• It may be difficult for the fund to pursue claims or enforce judgments against a foreign bank, depository or issuer of a security, or any of their agents, in the courts of a foreign country

• The value of the fund's foreign investments may also be affected by foreign tax laws, special U.S. tax considerations and restrictions on receiving the investment proceeds from a foreign country. Withholding and other non-U.S. taxes may

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decrease the fund's return. The value of the fund's foreign investments also may be affected by U.S. tax considerations and restrictions in receiving investment proceeds from a foreign country

• Some markets in which the fund may invest are located in parts of the world that have historically been prone to natural disasters that could result in a significant adverse impact on the economies of those countries and investments made in those countries

• It is often more expensive for the fund to buy, sell and hold securities in certain foreign markets than in the U.S.

• A governmental entity may delay, or refuse or be unable to pay, interest or principal on its sovereign debt due to cash flow problems, insufficient foreign currency reserves, political considerations, the relative size of the governmental entity's debt position in relation to the economy or the failure to put in place economic reforms

• Investing in depositary receipts is subject to many of the same risks as investing directly in non-U.S. issuers. Depositary receipts may involve higher expenses and may trade at a discount (or premium) to the underlying security. In addition, depositary receipts may not pass through voting and other shareholder rights, and may be less liquid than the underlying securities listed on an exchange

• A number of countries in the European Union (EU) have experienced, and may continue to experience, severe economic and financial difficulties. Additional EU member countries may also fall subject to such difficulties. A number of countries in Europe have suffered terror attacks, and additional attacks may occur in the future. In addition, the United Kingdom has withdrawn from the EU (commonly known as "Brexit"). The range and potential implications of possible political, regulatory, economic, and market outcomes of Brexit cannot be fully known but could be significant, potentially resulting in increased volatility, illiquidity and potentially lower economic growth in the affected markets, which will adversely affect the fund's investments, particularly in euro-denominated securities and derivative contracts, securities of issuers located in the EU or with significant exposure to EU issuers or countries

• China and other developing market countries may be subject to considerable degrees of economic, political and social instability. Markets in China and other Asian countries are relatively new and undeveloped. China's economic health is largely dependent upon exports, and may be dependent upon the economies of other Asian countries. Investments in Chinese and other Asian issuers could be adversely affected by changes in government policies, or trade or political disputes with major trading partners, including the U.S. China's growing trade surplus with the U.S. has given rise to trade disputes and the imposition of tariffs. The U.S. has also restricted the sale of certain goods to China. In addition, the U.S.

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government has imposed restrictions on U.S. investor participation in certain Chinese investments. These matters could adversely affect China's economy. China's central government exercises significant control over China's economy and may intervene in the financial markets, such as by imposing trading restrictions, and investments in Chinese issuers could be adversely affected by changes in government policies. The Chinese economy could be adversely affected by supply chain disruptions. The effect of China's recent relaxation of its zero-COVID policy on China's economy and global supply chains may not be fully known for some time. An economic slowdown in China could adversely affect economies of other emerging market countries that trade with China, as well as companies operating in those countries. Economies of Asian countries and Asian issuers could be adversely affected by regional security threats. In addition, China's long-running conflict over Taiwan's sovereignty, border disputes with many neighbors and historically strained relations with other Asian countries could result in military conflict that could adversely impact the economies of China and other Asian countries, disrupt supply chains, and severely affect global economies and markets

• If one or more stockholders of a supranational entity such as the World Bank fail to make necessary additional capital contributions, the entity may be unable to pay interest or repay principal on its debt securities

• Sanctions or other government actions against certain countries could negatively impact the fund's investments in securities that have exposure to those countries

• Russia launched a large-scale invasion of Ukraine on February 24, 2022. In response to the military action by Russia, various countries, including the U.S., the United Kingdom, and European Union, issued broad-ranging economic sanctions against Russia and Belarus and certain companies and individuals. Russia has taken retaliatory actions, including preventing repatriation of capital by U.S. and other investors. Since then, Russian securities have lost all, or nearly all, their market value, and many other issuers, securities and markets have been adversely affected. The ongoing conflict has resulted in significant market disruptions, including in certain markets, industries and sectors, such as the oil and natural gas markets, and negatively affected global supply chains, food supplies, inflation and global growth. The U.S. and other countries may impose sanctions on other countries, companies and individuals in light of Russia's military invasion. The extent and duration of the military action or future escalation of such hostilities, the extent and impact of existing and future sanctions, market disruptions and volatility, and the result of any diplomatic negotiations cannot be predicted. These and any related events could have a significant impact on the value and liquidity of certain fund investments, on fund performance and the value of an investment in the fund

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• Circumstances that impact one country could have profound impacts on other countries and on global economies or markets

Additional risks of investing in emerging markets include:

• The extent of economic development, political stability, market depth, infrastructure, capitalization and regulatory oversight can be less than in more developed markets. Emerging market economies tend to be less diversified than those of more developed countries. They typically have fewer medical and economic resources than more developed countries and thus they may be less able to control or mitigate the effects of a pandemic

• Emerging market countries may experience rising interest rates, or, more significantly, rapid inflation or hyperinflation

• The fund could experience a loss from settlement and custody practices in some emerging markets

• The possibility that a counterparty may not complete a currency or securities transaction

• Low trading volumes may result in a lack of liquidity and in extreme price volatility

**Currency risk.** Because the fund may invest in non-U.S. currencies, securities denominated in non-U.S. currencies, and other currency-related investments, the fund is subject to currency risk, meaning that the fund could experience losses based on changes in the exchange rate between non-U.S. currencies and the U.S. dollar or as a result of currency conversion costs. Currency exchange rates can be volatile, and are affected by factors such as general economic conditions, the actions of the U.S. and foreign governments or central banks, the imposition of currency controls and speculation.

**Equity securities risk.** Equity securities represent an ownership interest in an issuer, rank junior in a company's capital structure to debt securities and consequently may entail greater risk of loss than debt securities. Equity securities are subject to the risk that stock prices may rise and fall in periodic cycles and may perform poorly relative to other investments. This risk may be greater in the short term.

**Risks of convertible securities.** Convertible securities generally offer lower interest or dividend yields than non-convertible securities of similar quality. As with all fixed income securities, the market values of convertible securities tend to decline as interest rates increase and, conversely, to increase as interest rates decline. However, when the market price of the common stock underlying a convertible security approaches or exceeds the conversion price, the convertible security tends to reflect the market price of the underlying common stock. As the market price of the underlying common stock declines, the convertible security tends to trade increasingly on a yield basis and thus may not decline in price to the same extent

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as the underlying common stock. Convertible securities rank senior to common stocks in an issuer's capital structure and consequently entail less risk than the issuer's common stock. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible security is composed of two or more separate securities or instruments, each with its own market value. If the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.

**Preferred stocks risk**. Preferred stocks may pay fixed or adjustable rates of return. Preferred stocks are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company's preferred stocks generally pay dividends only after the company makes required payments to holders of its bonds and other debt. Thus, the value of preferred stocks will usually react more strongly than bonds and other debt to actual or perceived changes in the company's financial condition or prospects. The market value of preferred stocks generally decreases when interest rates rise. Also, the market prices of preferred stocks are more sensitive to changes in the issuer's creditworthiness than are the prices of debt securities. Generally, under normal circumstances, preferred stocks do not carry voting rights. Preferred stocks may trade less frequently and in a more limited volume and may be subject to more abrupt or erratic price movements than other securities. Preferred stocks of smaller companies may be more vulnerable to adverse developments than preferred stocks of larger companies.

**Risks of investment in other funds.** Investing in other investment companies, including exchange-traded funds (ETFs) and closed-end funds, subjects the fund to the risks of investing in the underlying securities or assets held by those funds. When investing in another fund, the fund will bear a pro rata portion of the underlying fund's expenses, including management fees, in addition to its own expenses. ETFs and closed-end funds are bought and sold based on market prices and can trade at a premium or a discount to the ETF's or closed-end fund's net asset value. Such funds may trade at a discount for an extended period and may not ever realize their net asset value.

**Derivatives risk.** Using swaps, forward foreign currency exchange contracts, bond and interest rate futures and other derivatives exposes the fund to special risks and costs and may result in losses to the fund, even when used for hedging purposes. Using derivatives can increase losses and reduce opportunities for gain when market prices, interest rates or currencies, or the derivative instruments themselves, behave in a way not anticipated by the fund, especially in abnormal market conditions. Using derivatives can have a leveraging effect (which may

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increase investment losses) and increase the fund's volatility, which is the degree to which the fund's share price may fluctuate within a short time period. Certain derivatives have the potential for unlimited loss, regardless of the size of the fund's initial investment. Derivatives are generally subject to the risks applicable to the assets, rates, indices or other indicators underlying the derivative. If changes in a derivative's value do not correspond to changes in the value of the fund's other investments or do not correlate well with the underlying assets, rate or index, the fund may not fully benefit from, or could lose money on, or could experience unusually high expenses as a result of, the derivative position. The other parties to certain derivative transactions present the same types of credit risk as issuers of fixed income securities. Derivatives also tend to involve greater liquidity risk and they may be difficult to value. The fund may be unable to terminate or sell its derivative positions. In fact, many over-the-counter derivatives will not have liquidity beyond the counterparty to the instrument. The fund also may have to sell assets at inopportune times to satisfy its obligations. Use of derivatives or similar instruments may have different tax consequences for the fund than an investment in the underlying security, and those differences may affect the amount, timing and character of income distributed to shareholders. The fund's use of derivatives may also increase the amount of taxes payable by shareholders. Risks associated with the use of derivatives are magnified to the extent that an increased portion of the fund's assets are committed to derivatives in general or are invested in just one or a few types of derivatives.

The U.S. government and foreign governments have adopted and implemented or are in the process of adopting and implementing regulations governing derivatives markets, including mandatory clearing of certain derivatives, margin and reporting requirements. The ultimate impact of the regulations remains unclear. Additional regulation of derivatives may make derivatives more costly, limit their availability or utility, otherwise adversely affect their performance or disrupt markets. The fund may be exposed to additional risks as a result of the additional regulations. The extent and impact of the regulations are not yet fully known and may not be for some time.

The fund will be required to maintain its positions with a clearing organization through one or more clearing brokers. The clearing organization will require the fund to post margin and the broker may require the fund to post additional margin to secure the fund's obligations. The amount of margin required may change from time to time. In addition, cleared transactions may be more expensive to maintain than over-the-counter transactions and may require the fund to deposit larger amounts of margin. The fund may not be able to recover margin amounts if the broker has financial difficulties. Also, the broker may require the fund to terminate

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**More on the risks of investing in the fund**

a derivatives position under certain circumstances. This may cause the fund to lose money. The fund's ability to use certain derivative instruments currently is limited by Commodity Futures Trading Commission rules.

**Credit default swap risk.** Credit default swap contracts, a type of derivative instrument, involve heightened risks and may result in losses to the fund. Credit default swaps may in some cases be illiquid and difficult to value, and they increase credit risk since the fund has exposure to both the issuer of the referenced obligation and the counterparty to the credit default swap. If the fund buys a credit default swap, it will be subject to the risk that the credit default swap may expire worthless, as the credit default swap would only generate income in the event of a default on the underlying debt security or other specified event. As a buyer, the fund would also be subject to credit risk relating to the seller's payment of its obligations in the event of a default (or similar event). If the fund sells a credit default swap, it will be exposed to the credit risk of the issuer of the obligation to which the credit default swap relates. As a seller, the fund would also be subject to leverage risk, because it would be liable for the full notional amount of the swap in the event of default (or similar event). Swaps may be difficult to unwind or terminate. Certain index-based credit default swaps are structured in tranches, whereby junior tranches assume greater default risk than senior tranches. The absence of a central exchange or market for swap transactions may lead, in some instances, to difficulties in trading and valuation, especially in the event of market disruptions. New regulations require many kinds of swaps to be executed through a centralized exchange or regulated facility and be cleared through a regulated clearinghouse. Although this clearing mechanism is generally expected to reduce counterparty credit risk, it may disrupt or limit the swap market and may not result in swaps being easier to trade or value. As swaps become more standardized, the fund may not be able to enter into swaps that meet its investment needs. The fund also may not be able to find a clearinghouse willing to accept the swaps for clearing. In a cleared swap, a central clearing organization will be the counterparty to the transaction. The fund will assume the risk that the clearinghouse may be unable to perform its obligations.

**Structured securities risk.** The structured securities in which the fund invests are a type of derivative instrument. The payment and credit qualities of these instruments derive from the underlying assets and the terms of the particular security, and they may behave in ways not anticipated by the fund. Some of these instruments may have the effect of increasing the fund's exposure to interest rate, market or credit risk, even if they are not primarily intended for these purposes. Distributions from collateral securities may not be adequate to make interest or other payments, and the quality of the collateral may decline in value or default. Investments in structured securities raise certain tax, legal, regulatory and accounting

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issues that may not be presented by direct investments in the underlying assets. These issues could be resolved in a manner that could hurt the performance of the fund. Certain structured securities are thinly traded or have limited trading markets. The structured securities may be subordinate to other classes.

**Risks of investing in inverse floating rate obligations.** The interest rate on inverse floating rate obligations will generally decrease as short-term interest rates increase, and increase as short-term rates decrease. Due to their leveraged structure, the sensitivity of the market value of an inverse floating rate obligation to changes in interest rates is generally greater than a comparable long-term bond issued by the same issuer and with similar credit quality, redemption and maturity provisions. Inverse floating rate obligations may be volatile and involve leverage risk.

**Forward foreign currency transactions risk.** To the extent that the fund enters into forward foreign currency transactions, it may not fully benefit from or may lose money on the transactions if changes in currency rates do not occur as anticipated or do not correspond accurately to changes in the value of the fund's holdings, or if the counterparty defaults. Such transactions may also prevent the fund from realizing profits on favorable movements in exchange rates. Risk of counterparty default is greater for counterparties located in emerging markets. The fund's ability to use forward foreign currency transactions successfully depends on a number of factors, including the forward foreign currency transactions being available at prices that are not too costly, the availability of liquid markets, and Amundi US's judgment regarding the direction of changes in currency exchange rates.

**Leveraging risk.** The value of your investment may be more volatile and other risks tend to be compounded if the fund borrows or uses derivatives or other investments, such as ETFs, that have embedded leverage. Leverage generally magnifies the effect of any increase or decrease in the value of the fund's underlying assets and creates a risk of loss of value on a larger pool of assets than the fund would otherwise have, potentially resulting in the loss of all assets. Engaging in such transactions may cause the fund to liquidate positions when it may not be advantageous to do so to satisfy its obligations. New derivatives regulations require the fund, to the extent it uses derivatives to a material extent, to, among other things, comply with certain overall limits on leverage. These regulations may limit the ability of the fund to pursue its investment strategies and may not be effective to mitigate the fund's risk of loss from derivatives.

**Repurchase agreement risk.** In the event that the other party to a repurchase agreement defaults on its obligations, the fund may encounter delay and incur costs before being able to sell the security. Such a delay may involve loss of interest

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**More on the risks of investing in the fund**

or a decline in price of the security. In addition, if the fund is characterized by a court as an unsecured creditor, it would be at risk of losing some or all of the principal and interest involved in the transaction.

**Market segment risk.** To the extent the fund emphasizes, from time to time, investments in a market segment, the fund will be subject to a greater degree to the risks particular to that segment, and may experience greater market fluctuation, than a fund without the same focus.

Industries in the financials segment, such as banks, insurance companies, broker-dealers and real estate investment trusts (REITs), may be sensitive to changes in interest rates, credit rating downgrades, decreased liquidity in credit markets, and general economic activity and are generally subject to extensive government regulation.

Industries in the consumer discretionary segment, such as consumer durables, hotels, restaurants, media, retailing and automobiles, may be significantly affected by the performance of domestic and international economies, interest rates, competition, consumer confidence and spending, and changes in demographics and consumer tastes.

Industries in the industrials segment, such as companies engaged in the production, distribution or service of products or equipment for manufacturing, agriculture, forestry, mining and construction, can be significantly affected by general economic trends, including such factors as employment and economic growth, interest rate changes, changes in consumer spending, legislative and governmental regulation and spending, import controls, litigation, liability for environmental damage and product liability claims, trading and tariff arrangements, trade disruptions, commodity prices and availability, exchange rates and worldwide competition. The value of securities issued by companies in the industrials sector may be adversely affected by supply and demand related to their specific products or services and industrials sector products in general. The products of manufacturing companies may face obsolescence due to rapid technological developments and frequent new product introduction.

Industries in the health care segment, such as health care supplies, health care services, biotechnology and pharmaceuticals, may be significantly affected by government regulation and reimbursement rates, approval of products by government agencies, and patent expirations, increases or decreases in the cost of medical products, services and patient care, shortages of skilled personnel and increased personnel costs, and product liability claims, among other factors. Many health care companies are heavily dependent on patent protection, and the expiration of

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a company's patent may adversely affect that company's profitability. Health care companies are subject to competitive forces that may result in price discounting, and may be thinly capitalized and susceptible to product obsolescence.

Industries in the materials segment, such as chemicals, construction materials, containers and packaging, metals and mining and paper and forest products, may be significantly affected by the level and volatility of commodity prices, currency rates, import controls and other regulations, labor relations, global competition and resource depletion.

Industries in the technology segment, such as information technology, communications equipment, computer hardware and software, and office and scientific equipment, are generally subject to risks of rapidly evolving technology, short product lives, rates of corporate expenditures, falling prices and profits, competition from new market entrants, and general economic conditions. They are also heavily dependent on intellectual property rights and may be adversely affected by the loss or impairment of, or inability to enforce, those rights.

**Valuation risk.** Many factors may influence the price at which the fund could sell any particular portfolio investment. The sales price may well differ - higher or lower - from the fund's valuation of the investment, and such differences could be significant, particularly for illiquid securities and securities that trade in thin markets and/or markets that experience extreme volatility. These differences may increase significantly and affect fund investments more broadly during periods of market volatility. Nearly all of the fund's investments are valued using fair value methodologies. Investors who purchase or submit a redemption request of fund shares may receive fewer or more shares, or lower or higher redemption proceeds, than they would have received if the securities had not been fair-valued or if a different valuation methodology had been used. Fixed income securities are typically valued using fair value methodologies. The value of foreign securities, certain fixed income securities and currencies, as applicable, may be materially affected by events after the close of the markets on which they are traded, but before the fund determines its net asset value. The fund's ability to value its investments may also be impacted by technological issues and/or errors by pricing services or other third party service providers.

**Redemption risk.** The fund may experience periods of heavy redemptions that could cause the fund to liquidate its assets at inopportune times or at a loss or depressed value, or accelerate taxable gains or transaction costs, particularly during periods of declining or illiquid markets. Redemption risk is greater to the extent that the fund has investors with large shareholdings, short investment horizons, or unpredictable cash flow needs. In addition, redemption risk is heightened during

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**More on the risks of investing in the fund**

periods of overall market turmoil. The redemption by one or more large shareholders of their holdings in the fund could hurt performance and/or cause the remaining shareholders in the fund to lose money. If one decision maker has control of fund shares owned by separate fund shareholders, including clients or affiliates of the fund's adviser, redemptions by these shareholders may further increase the fund's redemption risk. If the fund is forced to liquidate its assets under unfavorable conditions or at inopportune times, the value of your investment could decline.

**Cybersecurity risk.** Cybersecurity failures by and breaches of the fund's adviser, transfer agent, distributor, custodian, fund accounting agent or other service providers may disrupt fund operations, interfere with the fund's ability to calculate its NAV, prevent fund shareholders from purchasing, redeeming or exchanging shares or receiving distributions or receiving timely information regarding the fund or their investment in the fund, cause loss of or unauthorized access to private shareholder information, and result in financial losses to the fund and its shareholders, regulatory fines, penalties, reputational damage, or additional compliance costs. Substantial costs may be incurred in order to prevent any cyber incidents in the future. The fund and its shareholders could be negatively impacted as a result.

**Cash management risk.** The value of the investments held by the fund for cash management or temporary defensive purposes may be affected by market risks, changing interest rates and by changes in credit ratings of the investments. To the extent that the fund has any uninvested cash, the fund would be subject to credit risk with respect to the depository institution holding the cash. If the fund holds cash uninvested, the fund will not earn income on the cash and the fund's yield will go down. During such periods, it may be more difficult for the fund to achieve its investment objective.

**Expense risk.** Your actual costs of investing in the fund may be higher than the expenses shown in "Annual fund operating expenses" for a variety of reasons. For example, expense ratios may be higher than those shown if overall net assets decrease. Net assets are more likely to decrease and fund expense ratios are more likely to increase when markets are volatile.

To learn more about the fund's investments and risks, you should obtain and read the statement of additional information. Please note that there are many other factors that could adversely affect your investment and that could prevent the fund from achieving its goals.

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**Disclosure of portfolio holdings**

The fund's policies and procedures with respect to disclosure of the fund's securities are described in the statement of additional information.

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**Management**

**Investment adviser**

Amundi Asset Management US, Inc. ("Amundi US"), the fund's investment adviser, selects the fund's investments and oversees the fund's operations.

Amundi US is an indirect, wholly owned subsidiary of Amundi and Amundi's wholly owned subsidiary, Amundi Holdings US, Inc. Amundi, one of the world's largest asset managers, is headquartered in Paris, France. As of December 31, 2022, Amundi had more than $2.03 trillion in assets under management worldwide. As of December 31, 2022, Amundi US (and its U.S. affiliates) had over $88 billion in assets under management.

Amundi US's main office is at 60 State Street, Boston, Massachusetts 02109.

The firm's U.S. mutual fund investment history includes creating in 1928 one of the first mutual funds.

Amundi US has received an order from the Securities and Exchange Commission that permits Amundi US, subject to the approval of the fund's Board of Trustees, to hire and terminate a subadviser that is not affiliated with Amundi US (an "unaffiliated subadviser") or to materially modify an existing subadvisory contract with an unaffiliated subadviser for the fund without shareholder approval. Amundi US retains the ultimate responsibility to oversee and recommend the hiring, termination and replacement of any unaffiliated subadviser.

**Portfolio management**

Day-to-day management of the fund's portfolio is the responsibility of Jonathan Sharkey. Mr. Sharkey is supported by the fixed income team. Members of this team manage other Pioneer funds investing primarily in fixed income securities. The portfolio manager and the team also may draw upon the research and investment management expertise of the global research teams, which provide fundamental and quantitative research on companies and include members from one or more of Amundi US's affiliates. Mr. Sharkey, a Senior Vice President, joined Amundi US in 2006.

The fund's statement of additional information provides additional information about the portfolio manager's compensation, other accounts managed by the portfolio manager, and the portfolio manager's ownership of shares of the fund.

**Management fee**

The fund pays Amundi US a fee for managing the fund and to cover the cost of providing certain services to the fund.

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Amundi US's annual fee is equal to 0.60% of the fund's average daily net assets up to $500 million, 0.55% of the next $1.5 billion of the fund's average daily net assets and 0.50% of the fund's average daily net assets over $2 billion. The fee is accrued daily and paid monthly. <br>

For the fiscal year ended October 31, 2022, the fund paid management fees (excluding waivers and/or assumption of expenses) equivalent to 0.60% of the fund's average daily net assets.

A discussion regarding the basis for the Board of Trustees' approval of the management contract is available in the fund's annual report to shareholders for the period ended October 31, 2022.

**Distributor**

Amundi Distributor US, Inc. is the fund's distributor. The fund compensates the distributor for its services. The distributor is an affiliate of Amundi US.

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**Pricing of shares**

**Net asset value**

The fund's net asset value is the value of its securities plus any other assets minus its accrued operating expenses and other liabilities. The fund calculates a net asset value for each class of shares every day the New York Stock Exchange is open as of the close of regular trading (normally 4:00 p.m. Eastern time). On days when the New York Stock Exchange is closed for trading, including certain holidays listed in the statement of additional information, a net asset value is not calculated. The fund's most recent net asset value is available on the fund's website, amundi.com/us.

The fund generally values debt securities and certain derivative instruments by using the prices supplied by independent third party pricing services. A pricing service may use market prices or quotations from one or more brokers or other sources, a pricing matrix, or other fair value methods or techniques to provide an estimated value of the security or instrument. A pricing matrix is a means of valuing a debt security on the basis of current market prices for other debt securities, historical trading patterns in the market for fixed income securities and/or other factors. Non-U.S. debt securities that are listed on an exchange will be valued at the bid price obtained from an independent third party pricing service.

Senior loans are valued at the mean between the last available bid and asked prices for one or more brokers or dealers as obtained from an independent third party pricing service. If no reliable prices are available from either the primary or an alternative pricing service, broker quotes will be solicited. Event-linked bonds are valued at the bid price obtained from an independent third party pricing service. Other insurance-linked securities may be valued at the bid price obtained from an independent third party pricing service, or through a third party using a pricing matrix, insurance industry valuation models, or other fair value methods or techniques to provide an estimated value of the instrument.

The fund generally values its equity securities and certain derivative instruments that are traded on an exchange using the last sale price on the principal exchange on which they are traded. Equity securities that are not traded on the date of valuation, or securities for which no last sale prices are available, are valued at the mean between the last bid and asked prices or, if both last bid and asked prices are not available, at the last quoted bid price. Last sale, bid and asked prices are provided by independent third party pricing services. In the case of equity securities not traded on an exchange, prices are typically determined by independent third party pricing services using a variety of techniques and methods. Amundi US, the fund's valuation designee, may use a fair value model developed by an independent pricing service to value non-U.S. equity securities.

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To the extent that the fund invests in shares of other funds that are not traded on an exchange, such shares of other funds are valued at their net asset values as provided by those funds. The prospectuses for those funds explain the circumstances under which those funds will use fair value pricing methods and the effects of using fair value pricing methods.

The valuations of securities traded in non-U.S. markets and certain fixed income securities will generally be determined as of the earlier closing time of the markets on which they primarily trade. When the fund holds securities or other assets that are denominated in a foreign currency, the fund will normally use the currency exchange rates as of 3:00 p.m. (Eastern time). Non-U.S. markets are open for trading on weekends and other days when the fund does not price its shares. Therefore, the value of the fund's shares may change on days when you will not be able to purchase or redeem fund shares.

Amundi US has been designated as the fund's valuation designee, with responsibility for fair valuation subject to oversight by the fund's Board of Trustees. When independent third party pricing services are unable to supply prices for an investment, or when prices or market quotations are considered by Amundi US to be unreliable, the value of that security may be determined using quotations from one or more broker-dealers. When such prices or quotations are not available, or when they are considered by Amundi US to be unreliable, Amundi US uses other fair value methods to value the fund's securities. Amundi US also may use fair value methods if it is determined that a significant event has occurred between the time at which a price is determined and the time at which the fund's net asset value is calculated. Because the fund may invest in securities rated below investment grade – some of which may be thinly traded and for which prices may not be readily available or may be unreliable – Amundi US may use fair value methods more frequently with respect to the fund's investments than funds that primarily invest in securities that are more widely traded. Valuing securities using fair value methods may cause the net asset value of the fund's shares to differ from the net asset value that would be calculated only using market prices.

The prices used by Amundi US to value the fund's securities may differ from the amounts that would be realized if these securities were sold, and these differences may be significant, particularly for securities that trade in relatively thin markets and/or markets that experience extreme volatility.

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**Choosing a class of shares**

The fund offers four classes of shares through this prospectus. Each class has different eligibility requirements, sales charges and expenses, allowing you to choose the class that best meets your needs.

Factors you should consider include:

• The eligibility requirements that apply to purchases of a particular share class

• The expenses paid by each class

• The initial sales charges and contingent deferred sales charges (CDSCs), if any, applicable to each class

• Whether you qualify for any reduction or waiver of sales charges

• How long you expect to own the shares

• Any services you may receive from a financial intermediary

When choosing between Class A or Class C shares, you should be aware that, generally speaking, the longer your investment horizon, the more likely it will be that Class C shares will not be as advantageous as Class A shares. The annual distribution and service fees on Class C shares may cost you more over the longer term than the initial sales charge and distribution and service fees you would have paid for purchases of Class A shares.

If you are eligible to purchase Class K or Class Y shares, you should be aware that Class K and Class Y shares are not subject to an initial sales charge, CDSC or distribution and service fees and generally have lower annual expenses than Class A or Class C shares. However, if you invest in Class K shares or Class Y shares through an investment professional or financial intermediary, that investment professional or financial intermediary may charge you a commission in an amount determined and separately disclosed to you by that investment professional or financial intermediary.

Your investment professional can help you determine which class meets your goals. Your investment professional or financial intermediary may receive different compensation depending upon which class you choose, and may impose its own investment fees and practices for purchasing and selling fund shares, which are not described in this prospectus or in the statement of additional information. Consult your investment professional or financial intermediary about the availability of fund shares, the investment professional or financial intermediary's practices, and other information.

Please note that the fund does not charge any initial sales charge, CDSC or other asset-based fee for sales or distribution of Class K shares or Class Y shares. However, if you invest in Class K shares or Class Y shares through an investment professional

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or financial intermediary, that investment professional or financial intermediary may charge you a commission in an amount determined and separately disclosed to you by that investment professional or financial intermediary.

Because the fund is not party to any commission arrangement between you and your investment professional or financial intermediary, any purchases and redemptions of Class K shares or Class Y shares will be made by the fund at the applicable net asset value (before imposition of the sales commission). Any commissions charged by an investment professional or financial intermediary are not reflected in the fees and expenses listed in the fee table or expense example in this prospectus nor are they reflected in the performance in the bar chart and table in this prospectus because these commissions are not charged by the fund.

For information on the fund's expenses, please see "Fund Summary."

The availability of certain sales charge waivers and discounts may depend on whether you purchase and sell your shares directly from the fund or through a financial intermediary. Specific intermediaries may have different policies and procedures regarding the availability of front-end sales charge waivers or contingent deferred (back-end) sales charge (CDSC) waivers, which are discussed under "Intermediary defined sales charge waiver policies." In all instances, it is your responsibility to notify the fund or your financial intermediary at the time of purchase of any relationship or other facts qualifying you for sales charge waivers or discounts. For waivers and discounts not available through a particular intermediary, you will have to purchase fund shares directly from the fund or through another intermediary to receive these waivers or discounts. Please see the "Intermediary defined sales charge waiver policies" section to determine any sales charge discounts and waivers that may be available to you through your financial intermediary.

**Class A shares**

• You pay a sales charge of up to 4.50% of the offering price, which is reduced or waived for large purchases and certain types of investors. At the time of your purchase, your investment firm may receive a commission from the distributor of up to 4%, declining as the size of your investment increases.

• There is no contingent deferred sales charge, except in certain circumstances when no initial sales charge is charged.

• Distribution and service fees of 0.25% of average daily net assets.

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**Choosing a class of shares**

**Class C shares**

• A 1% contingent deferred sales charge is assessed if you sell your shares within one year of purchase. Your investment firm may receive a commission from the distributor at the time of your purchase of up to 1%.

• Distribution and service fees of 1.00% of average daily net assets.

• Maximum purchase amount (per transaction) of $499,999.

• Class C shares automatically convert to Class A shares after 8 years.

**Class K shares**

• No initial or contingent deferred sales charge. However, if you invest in Class K shares through an investment professional or financial intermediary, that investment professional or financial intermediary may charge you a commission in an amount determined and separately disclosed to you by that investment professional or financial intermediary.

• Initial investments by discretionary accounts and direct investors are subject to a $5 million investment minimum, which may be waived in some circumstances.

• There is no investment minimum for other eligible investors.

**Class Y shares**

• No initial or contingent deferred sales charge. However, if you invest in Class Y shares through an investment professional or financial intermediary, that investment professional or financial intermediary may charge you a commission in an amount determined and separately disclosed to you by that investment professional or financial intermediary.

• Initial investments are subject to a $5 million investment minimum, which may be waived in some circumstances.

**Share class eligibility**

**Class K shares**

Class K shares are available to certain discretionary accounts at Amundi US or its affiliates, certain direct investors, other funds in the Pioneer Funds mutual fund complex, and certain tax-deferred retirement plans (including 401(k) plans, employer-sponsored 403(b) plans, 457 plans, health savings accounts, profit sharing and money purchase pension plans, defined benefit plans and non-qualified deferred compensation plans) held in plan level or omnibus accounts.

Direct investors may be individuals, institutions, trusts, foundations and other institutional investors.

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Class K shares are also available to certain mutual fund programs. See "Minimum investment amounts - Waivers of the minimum investment amount for Class K."

**Automatic conversion of Class C Shares**

Class C shares automatically convert to Class A shares after 8 years. Conversions of Class C shares to Class A shares occur during the month of or following the 8th anniversary of the share purchase date. The automatic conversion is based on the relative net asset values of the two share classes without the imposition of a sales charge or fee. Generally, in order for your Class C shares to be eligible for automatic conversion to Class A shares, the fund or the financial intermediary through which you purchased your shares must have records which confirm that your Class C shares have been held for 8 years. Class C shares held through group retirement plan recordkeeping platforms of certain financial intermediaries that hold such shares in an omnibus account and do not track participant level share lot aging to facilitate such a conversion are not eligible for automatic conversion to Class A shares. Specific intermediaries may have different policies and procedures regarding the conversion of Class C shares to Class A shares

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**Distribution and service arrangements**

**Distribution plan**

The fund has adopted a distribution plan for Class A and Class C shares in accordance with Rule 12b-1 under the Investment Company Act of 1940. Under the plan, the fund pays distribution and service fees to the distributor. Because these fees are an ongoing expense of the fund, over time they increase the cost of your investment and your shares may cost more than shares that are subject to other types of sales charges.

**Additional payments to financial intermediaries**

Your financial intermediary may receive compensation from the fund, Amundi US or its affiliates for the sale of fund shares and related services. Compensation may include sales commissions and distribution and service (Rule 12b-1) fees, as well as compensation for administrative services and transaction processing.

Amundi US or its affiliates may make additional payments to your financial intermediary. These payments may provide your financial intermediary with an incentive to favor the Pioneer funds over other mutual funds or assist the distributor in its efforts to promote the sale of the fund's shares. Financial intermediaries include broker-dealers, banks (including bank trust departments), registered investment advisers, financial planners, retirement plan administrators and other types of intermediaries.

Amundi US or its affiliates make these additional payments (sometimes referred to as "revenue sharing") to financial intermediaries out of its own assets, which may include profits derived from services provided to the fund, or from the retention of a portion of sales charges or distribution and service fees. Amundi US may base these payments on a variety of criteria, including the amount of sales or assets of the Pioneer funds attributable to the financial intermediary or as a per transaction fee.

Not all financial intermediaries receive additional compensation and the amount of compensation paid varies for each financial intermediary. In certain cases, these payments may be significant. Amundi US determines which firms to support and the extent of the payments it is willing to make, generally choosing firms that have a strong capability to effectively distribute shares of the Pioneer funds and that are willing to cooperate with Amundi US's promotional efforts. Amundi US also may compensate financial intermediaries (in addition to amounts that may be paid by the fund) for providing certain administrative services and transaction processing services.

Amundi US may benefit from revenue sharing if the intermediary features the Pioneer funds in its sales system (such as by placing certain Pioneer funds on its preferred fund list or giving access on a preferential basis to members of the financial

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intermediary's sales force or management). In addition, the financial intermediary may agree to participate in the distributor's marketing efforts (such as by helping to facilitate or provide financial assistance for conferences, seminars or other programs at which Amundi US personnel may make presentations on the Pioneer funds to the intermediary's sales force). To the extent intermediaries sell more shares of the Pioneer funds or retain shares of the Pioneer funds in their clients' accounts, Amundi US receives greater management and other fees due to the increase in the Pioneer funds' assets. The intermediary may earn a profit on these payments if the amount of the payment to the intermediary exceeds the intermediary's costs.

The compensation that Amundi US pays to financial intermediaries is discussed in more detail in the fund's statement of additional information. Your intermediary may charge you additional fees or commissions other than those disclosed in this prospectus. Intermediaries may categorize and disclose these arrangements differently than in the discussion above and in the statement of additional information. You can ask your financial intermediary about any payments it receives from Amundi US or the Pioneer funds, as well as about fees and/or commissions it charges.

Amundi US and its affiliates may have other relationships with your financial intermediary relating to the provision of services to the Pioneer funds, such as providing omnibus account services or effecting portfolio transactions for the Pioneer funds. If your intermediary provides these services, Amundi US or the Pioneer funds may compensate the intermediary for these services. In addition, your intermediary may have other relationships with Amundi US or its affiliates that are not related to the Pioneer funds.

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**Sales charges**

**Initial sales charges (Class A shares only)**

You pay the offering price (the net asset value per share plus any initial sales charge) when you buy Class A shares unless you qualify to purchase shares at net asset value. You pay a lower sales charge as the size of your investment increases. You do not pay a sales charge when you reinvest dividends or capital gain distributions paid by the fund.

**Sales charges for Class A shares** 

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| | | |
|:---|:---|:---|
|  | **Sales charge as % of** | **Sales charge as % of** |
| **Amount of purchase**  | **Offering**<br> **price**<br>| **Net amount**<br> **invested**<br>|
| Less than $100,000  | 4.50  | 4.71 |
| $100,000 but less than $250,000 | 3.50  | 3.63 |
| $250,000 but less than $500,000  | 2.50 | 2.56 |
| $500,000 or more | -0- | -0- |

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The dollar amount of the sales charge is the difference between the offering price of the shares purchased (based on the applicable sales charge in the table) and the net asset value of those shares. Since the offering price is calculated to two decimal places using standard rounding methodology, the dollar amount of the sales charge as a percentage of the offering price and of the net amount invested for any particular purchase of fund shares may be higher or lower due to rounding.

**Reduced sales charges – Class A shares**

You may qualify for a reduced Class A sales charge if you own or are purchasing shares of Pioneer mutual funds. The investment levels required to obtain a reduced sales charge are commonly referred to as "breakpoints." Amundi US offers two principal means of taking advantage of breakpoints in sales charges for aggregate purchases of Class A shares of the Pioneer funds over time if:

• The amount of shares you own of the Pioneer funds plus the amount you are investing now is at least $100,000 (Rights of accumulation)

• You plan to invest at least $100,000 over the next 13 months (Letter of intent)

**Rights of accumulation – Class A shares only**

If you qualify for rights of accumulation, your sales charge will be based on the combined value (at the current offering price) of all your Pioneer mutual fund shares, the shares of your spouse and the shares of any children under the age of 21.

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**Letter of intent - Class A shares only**

You can use a letter of intent to qualify for reduced sales charges in <br> two situations:

• If you plan to invest at least $100,000 (excluding any reinvestment of dividends and capital gain distributions) in the fund's Class A shares during the next 13 months

• If you include in your letter of intent the value (at the current offering price) of all of your Class A shares of the fund and Class A shares of all other Pioneer mutual fund shares held of record in the amount used to determine the applicable sales charge for the fund shares you plan to buy

Completing a letter of intent does not obligate you to purchase additional shares, but if you do not buy enough shares to qualify for the projected level of sales charges by the end of the 13-month period (or when you sell your shares, if earlier), the distributor will recalculate your sales charge. Any share class for which no sales charge is paid cannot be included under the letter of intent. For more information regarding letters of intent, please contact your investment professional or obtain and read the statement of additional information.

**Qualifying for a reduced Class A sales charge**

In calculating your total account value in order to determine whether you have met sales charge breakpoints, you can include your Pioneer mutual fund shares, those of your spouse and the shares of any children under the age of 21. Amundi US will use each fund's current offering price to calculate your total account value. Certain trustees and fiduciaries may also qualify for a reduced sales charge.

To receive a reduced sales charge, you or your investment professional must, at the time of purchase, notify the distributor of your eligibility. In order to verify your eligibility for a discount, you may need to provide your investment professional or the fund with information or records, such as account numbers or statements, regarding shares of the fund or other Pioneer mutual funds held in all accounts by you, your spouse or children under the age of 21 with that investment professional or with any other financial intermediary. Eligible accounts may include joint accounts, retirement plan accounts, such as IRA and 401(k) accounts, and custodial accounts, such as ESA, UGMA and UTMA accounts.

It is your responsibility to confirm that your investment professional has notified the distributor of your eligibility for a reduced sales charge at the time of sale. If you or your investment professional do not notify the distributor of your eligibility, you will risk losing the benefits of a reduced sales charge.

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**Sales charges**

For this purpose, Pioneer mutual funds include any fund for which the distributor is principal underwriter and, at the distributor's discretion, may include funds organized outside the U.S. and managed by Amundi US or an affiliate.

You can locate information regarding the reduction or waiver of sales charges free of charge on Amundi US's website at amundi.com/us. The website includes hyperlinks that facilitate access to this information.

**Class A purchases at net asset value**

You may purchase Class A shares at net asset value (without a sales charge) as follows. If you believe you qualify for any of the Class A sales charge waivers discussed below, contact your investment professional or the distributor. You are required to provide written confirmation of your eligibility. You may not resell these shares except to or on behalf of the fund.

**Class A purchases at net asset value are available to:**

• Current or former trustees and officers of the fund;

• Partners and employees of legal counsel to the fund (at the time of initial share purchase);

• Directors, officers, employees or sales representatives of Amundi US and its affiliates (at the time of initial share purchase);

• Directors, officers, employees or sales representatives of any subadviser or a predecessor adviser (or their affiliates) to any investment company for which Amundi US serves as investment adviser (at the time of initial share purchase);

• Officers, partners, employees or registered representatives of broker-dealers (at the time of initial share purchase) which have entered into sales agreements with the distributor;

• Employees of Regions Financial Corporation and its affiliates (at the time of initial share purchase);

• Members of the immediate families of any of the persons above;

• Any trust, custodian, pension, profit sharing or other benefit plan of the foregoing persons;

• Insurance company separate accounts;

• Certain wrap accounts for the benefit of clients of investment professionals or other financial intermediaries adhering to standards established by the distributor;

• Other funds and accounts for which Amundi US or any of its affiliates serves as investment adviser or manager;

• Investors in connection with certain reorganization, liquidation or acquisition transactions involving other investment companies or personal holding companies;

• Certain unit investment trusts;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• Group employer-sponsored retirement plans with at least $500,000 in total plan assets. Waivers for group employer-sponsored retirement plans do not apply to traditional IRAs, Roth IRAs, SEPs, SARSEPs, SIMPLE IRAs, KEOGHs, individual 401(k) or individual 403(b) plans, or to brokerage relationships in which sales charges are customarily imposed;

• Group employer-sponsored retirement plans with accounts established with Amundi US on or before March 31, 2004 with 100 or more eligible employees or at least $500,000 in total plan assets;

• Participants in an employer-sponsored 403(b) plan or employer-sponsored 457 plan if (i) your employer has made special arrangements for your plan to operate as a group through a single broker, dealer or financial intermediary and (ii) all participants in the plan who purchase shares of a Pioneer mutual fund do so through a single broker, dealer or other financial intermediary designated by your employer;

• Investors purchasing shares pursuant to the reinstatement privilege applicable to Class A shares;

• Redemption proceeds from a non-retirement account used by the shareholder to purchase fund shares in an IRA or other individual-type retirement account: and

• Shareholders of record (i.e., shareholders whose shares are not held in the name of a broker or an omnibus account) on the date of the reorganization of a predecessor Safeco fund into a corresponding Pioneer fund, shareholders who owned shares in the name of an omnibus account provider on that date that agrees with the fund to distinguish beneficial holders in the same manner, and retirement plans with assets invested in the predecessor Safeco fund on that date.

In addition, Class A shares may be purchased at net asset value through certain mutual fund programs sponsored by qualified intermediaries, such as broker-dealers and investment advisers. In each case, the intermediary has entered into an agreement with Amundi US to include the Pioneer funds in their program without the imposition of a sales charge. The intermediary provides investors participating in the program with additional services, including advisory, asset allocation, recordkeeping or other services. You should ask your investment firm if it offers and you are eligible to participate in such a mutual fund program and whether participation in the program is consistent with your investment goals. The intermediaries sponsoring or participating in these mutual fund programs also may offer their clients other classes of shares of the funds, and investors may receive different levels of services or pay different fees depending upon the class of shares included in the program. Investors should consider carefully any separate transaction and other fees charged by these programs in connection with investing in each available share class before

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**Sales charges**

selecting a share class. Such mutual fund programs include certain self-directed brokerage services accounts held through qualified intermediaries that may or may not charge participating investors transaction fees.

**Contingent deferred sales charges (CDSCs)**

**Class A shares**

Purchases of Class A shares of $500,000 or more may be subject to a contingent deferred sales charge upon redemption. A contingent deferred sales charge is payable to the distributor in the event of a share redemption within 12 months following the share purchase at the rate of 1% of the lesser of the value of the shares redeemed (exclusive of reinvested dividend and capital gain distributions) or the total cost of such shares. However, the contingent deferred sales charge is waived for redemptions of Class A shares purchased by an employer-sponsored retirement plan that has at least $500,000 in total plan assets (or that has 1,000 or more eligible employees for plans with accounts established with Amundi US on or before March 31, 2004).

**Class C shares**

You buy Class C shares at net asset value per share without paying an initial sales charge. However, if you sell your Class C shares within one year of purchase, upon redemption you will pay the distributor a contingent deferred sales charge of 1% of the current market value or the original cost of the shares you are selling, whichever is less.

**Paying the contingent deferred sales charge (CDSC)**

Several rules apply for calculating CDSCs so that you pay the lowest possible CDSC.

• The CDSC is calculated on the current market value or the original cost of the shares you are selling, whichever is less

• You do not pay a CDSC on reinvested dividends or distributions

• If you sell only some of your shares, the transfer agent will first sell your shares that are not subject to any CDSC and then the shares that you have owned the longest

• CDSCs are not imposed when Class C shares are exchanged for Class C shares of another fund in the Pioneer Funds mutual fund complex, but the new shares will remain subject to the CDSC based on the original purchase date of the exchanged shares. The transfer agent processes exchanges in proportion to your shares subject to a CDSC, not subject to a CDSC, and purchased through reinvestment of dividends and distributions.

• You may qualify for a waiver of the CDSC normally charged. See "Waiver or reduction of contingent deferred sales charges"

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**Waiver or reduction of contingent deferred sales charges**

It is your responsibility to confirm that your investment professional has notified the distributor of your eligibility for a reduced sales charge at the time of sale. If you or your investment professional do not notify the distributor of your eligibility, you will risk losing the benefits of a reduced sales charge.

The distributor may waive or reduce the CDSC for Class A shares that are subject to a CDSC or for Class C shares if:

• The distribution results from the death of all registered account owners or a participant in an employer-sponsored plan. For UGMAs, UTMAs and trust accounts, the waiver applies only upon the death of all beneficial owners;

• You become disabled (within the meaning of Section 72 of the Internal Revenue Code of 1986, as amended (the "Internal Revenue Code")) after the purchase of the shares being sold. For UGMAs, UTMAs and trust accounts, the waiver only applies upon the disability of all beneficial owners;

• The distribution is made in connection with limited automatic redemptions as described in "Systematic withdrawal plans" (limited in any year to 10% of the value of the account in the fund at the time the withdrawal plan is established);

• The distribution is from any type of IRA, 403(b) or employer-sponsored plan described under Section 401(a) or 457 of the Internal Revenue Code and, in connection with the distribution, one of the following applies:

-

It is part of a series of substantially equal periodic payments made over the life expectancy of the participant or the joint life expectancy of the participant and his or her beneficiary (limited in any year to 10% of the value of the participant's account at the time the distribution amount is established);

-

It is a required minimum distribution due to the attainment of age 70½, in which case the distribution amount may exceed 10% (based solely on total plan assets held in Pioneer mutual funds);

-

It is rolled over to or reinvested in another fund in the Pioneer Funds mutual fund complex in the same class of shares, which will be subject to the CDSC of the shares originally held; or

-

It is in the form of a loan to a participant in a plan that permits loans (each repayment applied to the purchase of shares will be subject to a CDSC as though a new purchase);

• The distribution is to a participant in an employer-sponsored retirement plan described under Section 401(a) of the Internal Revenue Code or to a participant in an employer-sponsored 403(b) plan or employer-sponsored 457 plan if (i) your employer has made special arrangements for your plan to operate as a group through a single broker, dealer or financial intermediary and (ii) all participants

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**Sales charges**

in the plan who purchase shares of a Pioneer mutual fund do so through a single broker, dealer or other financial intermediary designated by your employer and is or is in connection with:

-

A return of excess employee deferrals or contributions;

-

A qualifying hardship distribution as described in the Internal Revenue Code;

-

Due to retirement or termination of employment;

-

From a qualified defined contribution plan and represents a participant's directed transfer, provided that this privilege has been preauthorized through a prior agreement with the distributor regarding participant directed transfers;

• The distribution is made pursuant to the fund's right to liquidate or involuntarily redeem shares in a shareholder's account;

• The distribution is made to pay an account's advisory or custodial fees; or

• The distributor does not pay the selling broker a commission normally paid at the time of the sale.

Please see the fund's statement of additional information for more information regarding reduced sales charges and breakpoints.

The availability of certain sales charge waivers and discounts may depend on whether you purchase your shares directly from the fund or through a financial intermediary. Please see the "Intermediary defined sales charge waiver policies" section for more information.

**Class K shares**

Class K shares are purchased at net asset value with no initial sales charge and no CDSC when redeemed. However, if you invest in Class K shares through an investment professional or financial intermediary, that investment professional or financial intermediary may charge you a commission in an amount determined and separately disclosed to you by that investment professional or financial intermediary.

**Class Y shares**

Class Y shares are purchased at net asset value with no initial sales charge and no CDSC when redeemed. However, if you invest in Class Y shares through an investment professional or financial intermediary, that investment professional or financial intermediary may charge you a commission in an amount determined and separately disclosed to you by that investment professional or financial intermediary.

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**Buying, exchanging and selling shares**

**Opening your account**

You may open an account by completing an account application and sending it to the fund by mail or by fax. Please call the fund to obtain an account application. Certain types of accounts, such as retirement accounts, have separate applications.

Use your account application to select options and privileges for your account. You can change your selections at any time by sending a completed account options form to the fund. You may be required to obtain a signature guarantee to make certain changes to an existing account.

Call or write to the fund for account applications, account options forms and other account information:

**Pioneer Funds** <br>P.O. Box 534427 <br>Pittsburgh, PA 15253-4427 <br>Telephone 1-800-225-6292

Please note that there may be a delay in receipt by the fund's transfer agent of applications submitted by regular mail to a post office address.

Each fund is generally available for purchase in the United States, Puerto Rico, Guam, American Samoa and the U.S. Virgin Islands. Except to the extent otherwise permitted by the funds' distributor, the funds will only accept accounts from U.S. citizens with a U.S. address (including an APO or FPO address) or resident aliens with a U.S. address (including an APO or FPO address) and a U.S. taxpayer identification number.

**Identity verification**

To help the government fight the funding of terrorism and money laundering activities, federal law requires all financial institutions to obtain, verify and record information that identifies each person who opens an account. When you open an account, you will need to supply your name, address, date of birth, and other information that will allow the fund to identify you.

The fund may close your account if we cannot adequately verify your identity. The redemption price will be the net asset value on the date of redemption.

**Investing through financial intermediaries and retirement plans**

If you invest in the fund through your financial intermediary or through a retirement plan, the options and services available to you may be different from those discussed in this prospectus. Shareholders investing through financial intermediaries, programs sponsored by financial intermediaries and retirement plans may only purchase funds and classes of shares that are available. When you invest through an account

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**Buying, exchanging and selling shares**

that is not in your name, you generally may buy and sell shares and complete other transactions only through the account. Ask your investment professional or financial intermediary for more information.

Additional conditions may apply to your investment in the fund, and the investment professional or intermediary may charge you a transaction-based, administrative or other fee for its services. These conditions and fees are in addition to those imposed by the fund and its affiliates. You should ask your investment professional or financial intermediary about its services and any applicable fees.

**Share prices for transactions**

If you place an order to purchase, exchange or sell shares that is received in good order by the fund's transfer agent or an authorized agent by the close of regular trading on the New York Stock Exchange (usually 4:00 p.m. Eastern time), the share price for your transaction will be based on the net asset value determined as of the close of regular trading on the New York Stock Exchange on that day (plus or minus any applicable sales charges). If your order is received by the fund's transfer agent or an authorized agent after the close of regular trading on the New York Stock Exchange, or your order is not in good order, the share price will be based on the net asset value next determined after your order is received in good order by the fund or authorized agent. The authorized agent is responsible for transmitting your order to the fund in a timely manner.

**Good order means that:**

• You have provided adequate instructions

• There are no outstanding claims against your account

• There are no transaction limitations on your account

• Your request includes a signature guarantee if you:

-

Are selling over $100,000 or exchanging over $500,000 worth of shares

-

Changed your account registration or address within the last 30 days

-

Instruct the transfer agent to mail the check to an address different from the one on your account

-

Want the check paid to someone other than the account's record owner(s)

-

Are transferring the sale proceeds to a Pioneer mutual fund account with a different registration

**Transaction limitations**

Your transactions are subject to certain limitations, including the limitation on the purchase of the fund's shares within 30 calendar days of a redemption. See "Excessive trading."

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**Buying**

You may buy fund shares from any financial intermediary that has a sales agreement or other arrangement with the distributor.

You can buy shares at net asset value per share plus any applicable sales charge. The distributor may reject any order until it has confirmed the order in writing and received payment. Normally, your financial intermediary will send your purchase request to the fund's transfer agent. **Consult your investment professional for more information.** Your investment firm receives a commission from the distributor, and may receive additional compensation from Amundi US, for your purchase of fund shares.

**Minimum investment amounts**

**Class A and Class C shares**

Your initial investment must be at least $1,000. Additional investments must be at least $100 for Class A shares and $500 for Class C shares.

You may qualify for lower initial or subsequent investment minimums if you are establishing an automatic investment plan or placing your trade through your investment firm. The fund may waive the initial or subsequent investment minimums. Minimum investment amounts may be waived for, among other things, share purchases made through certain mutual fund programs (e.g., asset based fee program accounts) sponsored by qualified intermediaries, such as broker-dealers and investment advisers, that have entered into an agreement with Amundi US.

**Class K shares**

Initial investments by discretionary accounts and direct investors in Class K shares must be at least $5 million. There is no investment minimum for other eligible investors. This amount may be invested in one or more of the Pioneer mutual funds that currently offer Class K shares. There is no minimum additional investment amount. The fund may waive the initial investment amount, if applicable.

**Waivers of the minimum investment amount for Class K**

The fund will accept an initial investment of less than $5 million if:

(a) The investment is made by a retirement plan that is an eligible investor in Class K shares; or

(b) The investment is made by another fund in the Pioneer Funds mutual fund complex; or

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**Buying, exchanging and selling shares**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

(c) The investment is made through certain mutual fund programs sponsored by qualified intermediaries, such as broker-dealers and investment advisers. In each case, the intermediary has an arrangement with Amundi US to include Class K shares of the Pioneer mutual funds in their program. In one model, the intermediary provides investors participating in the program with additional services, including advisory, asset allocation, recordkeeping or other services, as a combined service offering. In another model, a brokerage firm may provide transactional services in accordance with a commission schedule set by the firm. <br>You should ask your investment firm if it offers and you are eligible to participate in such a mutual fund program and whether participation in the program is consistent with your investment goals. The intermediaries sponsoring or participating in these mutual fund programs also may offer their clients other classes of shares of the funds, and investors may receive different levels of services or pay different fees depending upon the class of shares included in the program. Investors should consider carefully any separate transaction and other fees charged by these programs in connection with investing in each available share class before selecting a share class.

The fund reserves the right to waive the initial investment minimum in other circumstances.

**Class Y shares**

Your initial investment in Class Y shares must be at least $5 million. This amount may be invested in one or more of the Pioneer mutual funds that currently offer Class Y shares. There is no minimum additional investment amount. The fund may waive the initial investment amount.

**Waivers of the minimum investment amount for Class Y**

The fund will accept an initial investment of less than $5 million if:

(a) The investment is made by a trust company or bank trust department which is initially investing at least $1 million in any of the Pioneer mutual funds and, at the time of the purchase, such assets are held in a fiduciary, advisory, custodial or similar capacity over which the trust company or bank trust department has full or shared investment discretion; or

(b) The investment is at least $1 million in any of the Pioneer mutual funds and the purchaser is an insurance company separate account; or

(c) The account is not represented by a broker-dealer and the investment is made by (1) an ERISA-qualified retirement plan that meets the requirements of Section 401 of the Internal Revenue Code, (2) an employer-sponsored retirement

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plan that meets the requirements of Sections 403 or 457 of the Internal Revenue Code, (3) a private foundation that meets the requirements of Section 501(c)(3) of the Internal Revenue Code or (4) an endowment or other organization that meets the requirements of Section 509(a)(1) of the Internal Revenue Code; or

(d) The investment is made by an employer-sponsored retirement plan established for the benefit of (1) employees of Amundi US or its affiliates, or (2) employees or the affiliates of broker-dealers who have a Class Y shares sales agreement with the distributor; or

(e) The investment is made through certain mutual fund programs sponsored by qualified intermediaries, such as broker-dealers and investment advisers. In each case, the intermediary has an arrangement with Amundi US to include Class Y shares of the Pioneer mutual funds in its program. In one model, the intermediary provides investors participating in the program with additional services, including advisory, asset allocation, recordkeeping or other services, as a combined service offering. In another model, a brokerage firm may provide transactional services in accordance with a commission schedule set by the firm.

You should ask your investment firm if it offers and you are eligible to participate in such a mutual fund program and whether participation in the program is consistent with your investment goals. The intermediaries sponsoring or participating in these mutual fund programs also may offer their clients other classes of shares of the funds, and investors may receive different levels of services or pay different fees depending upon the class of shares included in the program. Investors should consider carefully any separate transaction and other fees charged by these programs in connection with investing in each available share class before selecting a share class; or

(f) The investment is made by another fund in the Pioneer Funds mutual fund complex.

The fund reserves the right to waive the initial investment minimum in other circumstances.

**Maximum purchase amounts**

Purchases of fund shares are limited to $499,999 for Class C shares. This limit is applied on a per transaction basis. Class A, Class K and Class Y shares are not subject to a maximum purchase amount.

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**Buying, exchanging and selling shares**

**Retirement plan accounts**

You can purchase fund shares through tax-deferred retirement plans for individuals, businesses and tax-exempt organizations.

Your initial investment for most types of retirement plan accounts must be at least $1,000. Additional investments for most types of retirement plans must be at least $100.

You may not use the account application accompanying this prospectus to establish an Amundi US retirement plan. You can obtain retirement plan applications from your investment firm or by calling the Retirement Plans Department at 1-800-622-0176.

**How to buy shares**

**Through your investment firm**

Normally, your investment firm will send your purchase request to the fund's distributor and/or transfer agent. **Consult your investment professional for more information.** Your investment firm receives a commission from the distributor, and may receive additional compensation from Amundi US, for your purchase of fund shares.

**By phone or online**

**You can use the telephone or online purchase privilege if** you have an existing non-retirement account. Certain IRAs can use the telephone purchase privilege. If your account is eligible, you can purchase additional fund shares by phone or online if:

• You established your bank account of record at least 30 days ago

• Your bank information has not changed for at least 30 days

• You are not purchasing more than $100,000 worth of shares per account per day

• You can provide the proper account identification information

When you request a telephone or online purchase, the fund's transfer agent will electronically debit the amount of the purchase from your bank account of record. The fund's transfer agent will purchase fund shares for the amount of the debit at the offering price determined after the fund's transfer agent receives your telephone or online purchase instruction and good funds. It usually takes three business days for the fund's transfer agent to receive notification from your bank that good funds are available in the amount of your investment.

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**In writing, by mail**

You can purchase fund shares for an existing fund account by **mailing a check to the fund**. Make your check payable to the fund. Neither initial nor subsequent investments should be made by third party check, travelers check, or credit card check. Your check must be in U.S. dollars and drawn on a U.S. bank. Include in your purchase request the fund's name, the account number and the name or names in the account registration. Please note that there may be a delay in receipt by the fund's transfer agent of purchase orders submitted by regular mail to a post office address.

**By wire (Class K or Class Y shares only)**

If you have an existing (Class K or Class Y shares only) account, you may wire funds to purchase shares. Note, however, that:

• BNY Mellon must receive your wire no later than 11:00 a.m. Eastern time on the business day after the fund receives your request to purchase shares

• If BNY Mellon does not receive your wire by 11:00 a.m. Eastern time on the next business day, your transaction will be canceled at your expense and risk

• Wire transfers normally take two or more hours to complete and a fee may be charged by the sending bank

• Wire transfers may be restricted on holidays and at certain other times

**Instruct your bank to wire funds to:** 

Receiving Bank: BNY Mellon, NA ABA Routing No. 011001234 BNY Mellon Investment Servicing (US) Inc. as agent FBO Amundi US Funds Consolidated Account Account 727296 <br> For further credit to: Shareholder Name Existing Pioneer Account No. Floating Rate Fund

The fund's transfer agent must receive your account application before you send your initial check or federal funds wire. In addition, you must provide a bank wire address of record when you establish your account.

**Exchanging**

You may, under certain circumstances, exchange your shares for shares of the same class of another fund in the Pioneer Funds mutual fund complex.

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**Buying, exchanging and selling shares**

Your exchange request must be for at least $1,000. The fund allows you to exchange your shares at net asset value without charging you either an initial or contingent deferred sales charge at the time of the exchange. Shares you acquire as part of an exchange will continue to be subject to any contingent deferred sales charge that applies to the shares you originally purchased. When you ultimately sell your shares, the date of your original purchase will determine your contingent deferred sales charge.

Before you request an exchange, consider each fund's investment objective(s) and policies as described in the fund's prospectus. You generally will have to pay income taxes on an exchange.

**Same-fund exchange privilege**

Certain shareholders may be eligible to exchange their shares for shares of another class. If eligible, no sales charges or other charges will apply to any such exchange. Generally, shareholders will not recognize a gain or loss for federal income tax purposes upon such an exchange. Investors should contact their financial intermediary to learn more about the details of this privilege.

**How to exchange shares**

**Through your investment firm**

Normally, your investment firm will send your exchange request to the fund's transfer agent. **Consult your investment professional for more information about exchanging your shares.** 

**By phone or online**

After you establish an eligible fund account, **you can exchange fund shares by phone or online if:**

• You are exchanging into an existing account or using the exchange to establish a new account, provided the new account has a registration identical to the original account

• The fund into which you are exchanging offers the same class of shares

• You are not exchanging more than $500,000 worth of shares per account per day

• You can provide the proper account identification information

**In writing, by mail or by fax**

You can exchange fund shares by **mailing or faxing a letter of instruction to the fund.** You can exchange fund shares directly through the fund only if your account is registered in your name. However, you may not fax an exchange request for more than $500,000. Include in your letter:

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• The name and signature of all registered owners

• A signature guarantee for each registered owner if the amount of the exchange is more than $500,000

• The name of the fund out of which you are exchanging and the name of the fund into which you are exchanging

• The class of shares you are exchanging

• The dollar amount or number of shares you are exchanging

Please note that there may be a delay in receipt by the fund's transfer agent of exchange requests submitted by regular mail to a post office address.

**Selling**

Your shares will be sold at the share price (net asset value less any applicable sales charge) next calculated after the fund or its authorized agent, such as a broker-dealer, receives your request in good order. If a signature guarantee is required, you must submit your request in writing.

If the shares you are selling are subject to a deferred sales charge, it will be deducted from the sale proceeds. The fund generally will send your sale proceeds by check, bank wire or electronic funds transfer. Your redemption proceeds normally will be sent within 1 business day after your request is received in good order, but in any event within 7 days, regardless of the method the fund uses to make such payment. If you recently sent a check to purchase the shares being sold, the fund may delay payment of the sale proceeds until your check has cleared. This may take up to 10 calendar days from the purchase date.

Your redemption proceeds may be delayed, or your right to receive redemption proceeds suspended, if the New York Stock Exchange is closed (other than on weekends or holidays) or trading is restricted, if the Securities and Exchange Commission determines an emergency or other circumstances exist that make it impracticable for the fund to sell or value its portfolio securities, or otherwise as permitted by the rules of or by the order of the Securities and Exchange Commission.

If you are selling shares from a non-retirement account or certain IRAs, you may use any of the methods described below. If you are selling shares from a retirement account other than an IRA, you must make your request in writing.

You generally will have to pay income taxes on a sale.

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**Buying, exchanging and selling shares**

If you must use a written request to exchange or sell your shares and your account is registered in the name of a corporation or other fiduciary you must include the name of an authorized person and a certified copy of a current corporate resolution, certificate of incumbency or similar legal document showing that the named individual is authorized to act on behalf of the record owner.

Under normal circumstances, the fund expects to meet redemption requests by using cash or cash equivalents in its portfolio and/or selling portfolio assets to generate cash. Under stressed or abnormal market conditions or circumstances, including circumstances adversely affecting the liquidity of the fund's investments, the fund may be more likely to be forced to sell portfolio assets to meet redemptions than under normal market circumstances. Under such circumstances, the fund could be forced to liquidate assets at inopportune times or at a loss or depressed value. The fund also may pay redemption proceeds using cash obtained through a committed, unsecured revolving credit facility, or an interfund lending facility, if available, and other borrowing arrangements that may be available from time to time.

The fund reserves the right to redeem in kind, that is, to pay all or a portion of your redemption proceeds by giving you securities. If the fund redeems in kind, it generally will deliver to you a proportionate share of the portfolio securities owned by the fund. Securities you receive this way may increase or decrease in value while you hold them and you may incur brokerage and transaction charges and tax liability when you convert the securities to cash. The fund may redeem in kind at a shareholder's request or if, for example, the fund reasonably believes that a cash redemption may have a substantial impact on the fund and its remaining shareholders.

During periods of deteriorating or stressed market conditions, when an increased portion of the fund's portfolio may be comprised of less-liquid investments, or during extraordinary or emergency circumstances, the fund may be more likely to pay redemption proceeds with cash obtained through short-term borrowing arrangements (if available) or by giving you securities.

**How to sell shares**

**Through your investment firm**

Normally, your investment firm will send your request to sell shares to the fund's transfer agent. Please note that your investment firm may have its own earlier deadlines for the receipt of a request to sell shares. **Consult your investment professional for more information.** The fund has authorized the distributor to act as its agent in the repurchase of fund shares from qualified investment firms. The fund reserves the right to terminate this procedure at any time.

------

**By phone or online**

**If you have an eligible non-retirement account, you may sell up to $100,000 per account per day by phone or online.** You may sell fund shares held in a retirement plan account by phone only if your account is an eligible IRA (tax penalties may apply). You may not sell your shares by phone or online if you have changed your address (for checks) or your bank information (for wires and transfers) in the last 30 days.

You may receive your sale proceeds:

• By check, provided the check is made payable exactly as your account is registered

• By bank wire or by electronic funds transfer, provided the sale proceeds are being sent to your bank address of record

For Class Y shares, shareholders may sell up to $5 million per account per day if the proceeds are directed to your bank account of record ($100,000 per account per day if the proceeds are not directed to your bank account of record).

**In writing, by mail or by fax**

You can sell some or all of your fund shares by **writing directly to the fund** only if your account is registered in your name. Include in your request your name, the fund's name, your fund account number, the class of shares to be sold, the dollar amount or number of shares to be sold and any other applicable requirements as described below. The fund's transfer agent will send the sale proceeds to your address of record unless you provide other instructions. Your request must be signed by all registered owners and be in good order.

The fund's transfer agent will not process your request until it is received in good order.

You may sell up to $100,000 per account per day by fax.

Please note that there may be a delay in receipt by the fund's transfer agent of redemption requests submitted by regular mail to a post office address.

**How to contact us**

**By phone**

For information or to request a telephone transaction between 8:00 a.m. and 7:00 p.m. (Eastern time) by speaking with a shareholder services <br> representative call <br>**1-800-225-6292**

To request a transaction using FactFone<sup>SM</sup> call <br>**1-800-225-4321**

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**Buying, exchanging and selling shares**

**By mail**

Send your written instructions to: <br>**Pioneer Funds** <br>P.O. Box 534427 <br>Pittsburgh, PA 15253-4427

**Amundi US website**

amundi.com/us

**By fax**

Fax your exchange and sale requests to: <br>**1-800-225-4240**

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**Account options**

See the account application form for more details on each of the following services or call the fund for details and availability.

**Telephone transaction privileges**

If your account is registered in your name, you can buy, exchange or sell fund shares by telephone. If you do not want your account to have telephone transaction privileges, you must indicate that choice on your account application or by writing to the fund.

When you request a telephone transaction the fund's transfer agent will try to confirm that the request is genuine. The transfer agent records the call, requires the caller to provide validating information for the account and sends you a written confirmation. The fund may implement other confirmation procedures from time to time. Different procedures may apply if you have a non-U.S. account or if your account is registered in the name of an institution, broker-dealer or other third party. If the fund's confirmation procedures are followed, neither the fund nor its agents will bear any liability for these transactions.

**Online transaction privileges**

If your account is registered in your name, you may be able to buy, exchange or sell fund shares online. Your investment firm may also be able to buy, exchange or sell your fund shares online.

To establish online transaction privileges:

• For new accounts, complete the online section of the account application

• For existing accounts, complete an account options form, write to the <br> fund or complete the online authorization screen at amundi.com/us

To use online transactions, you must read and agree to the terms of an online transaction agreement available on the Amundi US website. When you or your investment firm requests an online transaction, the fund's transfer agent electronically records the transaction, requires an authorizing password and sends a written confirmation. The fund may implement other procedures from time to time. Different procedures may apply if you have a non-U.S. account or if your account is registered in the name of an institution, broker-dealer or other third party. You may not be able to use the online transaction privilege for certain types of accounts, including most retirement accounts.

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**Account options**

**Periodic investments**

You can make periodic investments in the fund by setting up monthly bank drafts, government allotments, payroll deductions, or an Automatic Investment Plan. Periodic investments may be made only through U.S. banks. You may use a periodic investment plan to establish a Class A share account with a small initial investment. If you have a Class C share account and your balance is at least $1,000, you may establish a periodic investment plan.

**Automatic Investment Plan (AIP)**

If you establish an Automatic Investment Plan with Amundi US, the fund's transfer agent will make a periodic investment in fund shares by means of a preauthorized electronic funds transfer from your bank account. Your plan investments are voluntary. You may discontinue your plan at any time or change the plan's dollar amount, frequency or investment date by calling or writing to the fund's transfer agent. You should allow up to 30 days for the fund's transfer agent to establish your plan.

**Automatic exchanges**

You can automatically exchange your fund shares for shares of the same class of another fund in the Pioneer Funds mutual fund complex. The automatic exchange will begin on the day you select when you complete the appropriate section of your account application or an account options form. In order to establish automatic exchange:

• You must select exchanges on a monthly or quarterly basis

• Both the originating and receiving accounts must have identical registrations

• The originating account must have a minimum balance of $5,000

You may have to pay income taxes on an exchange.

**Distribution options**

The fund offers three distribution options. Any fund shares you buy by reinvesting distributions will be priced at the applicable net asset value per share.

(1) Unless you indicate another option on your account application, any dividends and capital gain distributions paid to you by the fund will automatically be invested in additional fund shares.

(2) You may elect to have the amount of any dividends paid to you in cash and any capital gain distributions reinvested in additional shares.

(3) You may elect to have the full amount of any dividends and/or capital gain distributions paid to you in cash.

------

Options (2) and (3) are not available to retirement plan accounts or accounts with a current value of less than $500. When electing a cash distribution option, you may only select one destination for the cash distribution portion (i.e., bank account or directed to another mutual fund). The other distribution portion must be reinvested into your current mutual fund account or follow the same cash election.

If you are under 59½, taxes and tax penalties may apply.

If your distribution check is returned to the fund's transfer agent or you do not cash the check for six months or more, the fund's transfer agent may reinvest the amount of the check in your account and automatically change the distribution option on your account to option (1) until you request a different option in writing. If the amount of a distribution check would be less than $25, the fund may reinvest the amount in additional shares of the fund instead of sending a check. Additional shares of the fund will be purchased at the then-current net asset value.

**Directed dividends**

You can invest the dividends paid by one of your Pioneer mutual fund accounts in a second Pioneer mutual fund account. The value of your second account must be at least $1,000. You may direct the investment of any amount of dividends. There are no fees or charges for directed dividends.

**Systematic withdrawal plans**

When you establish a systematic withdrawal plan for your account, the transfer agent will sell the number of fund shares you specify on a periodic basis and the proceeds will be paid to you or to any person you select. You must obtain a signature guarantee to direct payments to another person after you have established your systematic withdrawal plan. Payments can be made either by check or by electronic transfer to a U.S. bank account you designate.

To establish a systematic withdrawal plan:

• Your account must have a total value of at least $10,000 when you establish your plan

• You may not request a periodic withdrawal of more than 10% of the value of any Class C share account (valued at the time the plan is implemented)

These requirements do not apply to scheduled (Internal Revenue Code Section 72(t) election) or mandatory (required minimum distribution) withdrawals from IRAs and certain retirement plans.

------

**Account options**

Systematic sales of fund shares may be taxable transactions for you. While you are making systematic withdrawals from your account, you may pay unnecessary initial sales charges on additional purchases of Class A shares or contingent deferred sales charges.

**Direct deposit**

If you elect to take dividends or dividends and capital gain distributions in cash, or if you establish a systematic withdrawal plan, you may choose to have those cash payments deposited directly into your savings, checking or NOW bank account.

**Voluntary tax withholding**

You may have the fund's transfer agent withhold 28% of the dividends and capital gain distributions paid from your fund account (before any reinvestment) and forward the amount withheld to the Internal Revenue Service as a credit against your federal income taxes. Voluntary tax withholding is not available for retirement plan accounts or for accounts subject to backup withholding.

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**Shareholder services and policies**

**Excessive trading**

Frequent trading into and out of the fund can disrupt portfolio management strategies, harm fund performance by forcing the fund to hold excess cash or to liquidate certain portfolio securities prematurely and increase expenses for all investors, including long-term investors who do not generate these costs. An investor may use short-term trading as a strategy, for example, if the investor believes that the valuation of the fund's portfolio securities for purposes of calculating its net asset value does not fully reflect the then-current fair market value of those holdings. The fund discourages, and does not take any intentional action to accommodate, excessive and short-term trading practices, such as market timing. Although there is no generally applied standard in the marketplace as to what level of trading activity is excessive, we may consider trading in the fund's shares to be excessive for a variety of reasons, such as if:

• You sell shares within 30 days after the shares were purchased;

• You make two or more purchases and redemptions within a short period of time;

• You enter into a series of transactions that indicate a timing pattern or strategy; or

• We reasonably believe that you have engaged in such practices in connection with other mutual funds.

The fund's Board of Trustees has adopted policies and procedures with respect to frequent purchases and redemptions of fund shares by fund investors. Pursuant to these policies and procedures, we monitor selected trades on a daily basis in an effort to detect excessive short-term trading. If we determine that an investor or a client of a broker or other intermediary has engaged in excessive short-term trading that we believe may be harmful to the fund, we will ask the investor, broker or other intermediary to cease such activity and we will refuse to process purchase orders (including purchases by exchange) of such investor, broker, other intermediary or accounts that we believe are under their control. In determining whether to take such actions, we seek to act in a manner that is consistent with the best interests of the fund's shareholders.

While we use our reasonable efforts to detect excessive trading activity, there can be no assurance that our efforts will be successful or that market timers will not employ tactics designed to evade detection. If we are not successful, your return from an investment in the fund may be adversely affected. Frequently, fund shares are held through omnibus accounts maintained by financial intermediaries such as brokers and retirement plan administrators, where the holdings of multiple shareholders, such as all the clients of a particular broker or other intermediary, are aggregated. Our ability to monitor trading practices by investors purchasing shares through omnibus accounts may be limited and dependent upon the cooperation of the broker or other intermediary in taking steps to limit this type of activity.

------

**Shareholder services and policies**

The fund may reject a purchase or exchange order before its acceptance or the issuance of shares. The fund may also restrict additional purchases or exchanges in an account. Each of these steps may be taken for any transaction, for any reason, without prior notice, including transactions that the fund believes are requested on behalf of market timers. The fund reserves the right to reject any purchase or exchange request by any investor or financial institution if the fund believes that any combination of trading activity in the account or related accounts is potentially disruptive to the fund. A prospective investor whose purchase or exchange order is rejected will not achieve the investment results, whether gain or loss, that would have been realized if the order had been accepted and an investment made in the fund. A fund and its shareholders do not incur any gain or loss as a result of a rejected order. The fund may impose further restrictions on trading activities by market timers in the future.

To limit the negative effects of excessive trading on the fund, the fund has adopted the following restriction on investor transactions. If an investor redeems $5,000 or more (including redemptions that are a part of an exchange transaction) from the fund, that investor shall be prevented (or "blocked") from purchasing shares of the fund (including purchases that are a part of an exchange transaction) for 30 calendar days after the redemption. This policy does not apply to systematic purchase or withdrawal plan transactions, transactions made through employer-sponsored retirement plans described under Section 401(a), 403(b) or 457 of the Internal Revenue Code or employee benefit plans, scheduled (Internal Revenue Code Section 72(t) election) or mandatory (required minimum distribution) withdrawals from IRAs, rebalancing transactions made through certain asset allocation or "wrap" programs, transactions by insurance company separate accounts or transactions by other funds that invest in the fund. This policy does not apply to purchase or redemption transactions of less than $5,000 or to Pioneer U.S. Government Money Market Fund or Pioneer Multi-Asset Ultrashort Income Fund.

We rely on financial intermediaries that maintain omnibus accounts to apply to their customers either the fund's policy described above or their own policies or restrictions designed to limit excessive trading of fund shares. However, we do not impose this policy at the omnibus account level.

Purchases pursuant to the reinstatement privilege (for Class A shares) are subject to this policy.

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**Purchases in kind**

You may use securities you own to purchase shares of the fund provided that Amundi US, in its sole discretion, determines that the securities are consistent with the fund's objective and policies and their acquisition is in the best interests of the fund. If the fund accepts your securities, they will be valued for purposes of determining the number of fund shares to be issued to you in the same way the fund will value the securities for purposes of determining its net asset value. For federal income tax purposes, you may be taxed in the same manner as if you sold the securities that you use to purchase fund shares for cash in an amount equal to the value of the fund shares that you purchase. Your broker may also impose a fee in connection with processing your purchase of fund shares with securities.

**Reinstatement privilege (Class A shares)**

If you recently sold all or part of your Class A shares, you may be able to reinvest all or part of your sale proceeds without a sales charge in Class A shares of any Pioneer mutual fund. To qualify for reinstatement:

• You must send a written request to the fund no more than 90 days after selling your shares and

• The registration of the account in which you reinvest your sale proceeds must be identical to the registration of the account from which you sold your shares.

Purchases pursuant to the reinstatement privilege are subject to limitations on investor transactions, including the limitation on the purchase of the fund's shares within 30 calendar days of redemption. See "Excessive trading."

When you elect reinstatement, you are subject to the provisions outlined in the selected fund's prospectus, including the fund's minimum investment requirement. Your sale proceeds will be reinvested in shares of the fund at the Class A net asset value per share determined after the fund receives your written request for reinstatement. You may realize a gain or loss for federal income tax purposes as a result of your sale of fund shares, and special tax rules may apply if you elect reinstatement. Consult your tax adviser for more information.

**Amundi US website** <br>**amundi.com/us**

The website includes a full selection of information on mutual fund investing. You can also use the website to get:

• Your current account information

• Prices, returns and yields of all publicly available Pioneer mutual funds

• Prospectuses, statements of additional information and shareowner reports for all the Pioneer mutual funds

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**Shareholder services and policies**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• A copy of Amundi US's privacy notice

If you or your investment firm authorized your account for the online transaction privilege, you may buy, exchange and sell shares online.

**FactFone**<sup>SM</sup> **1-800-225-4321**

You can use FactFone<sup>SM</sup> to:

• Obtain current information on your Pioneer mutual fund accounts

• Inquire about the prices of all publicly available Pioneer mutual funds

• Make computer-assisted telephone purchases, exchanges and redemptions for your fund accounts

• Request account statements

If you plan to use FactFone<sup>SM</sup> to make telephone purchases and redemptions, first you must activate your personal identification number and establish your bank account of record. If your account is registered in the name of a broker-dealer or other third party, you may not be able to use FactFone<sup>SM</sup> to obtain account information.

**Household delivery of fund documents**

With your consent, Amundi US may send a single proxy statement, prospectus and shareowner report to your residence for you and any other member of your household who has an account with the fund. If you wish to revoke your consent to this practice, you may do so by notifying Amundi US, by phone or in writing (see "How to contact us"). Amundi US will begin mailing separate proxy statements, prospectuses and shareowner reports to you within 30 days after receiving your notice.

**Confirmation statements**

The fund's transfer agent maintains an account for each investment firm or individual shareowner and records all account transactions. You will be sent confirmation statements showing the details of your transactions as they occur, except automatic investment plan transactions, which are confirmed quarterly. If you have more than one Pioneer mutual fund account registered in your name, the Pioneer combined account statement will be mailed to you each quarter.

**Tax information**

Early each year, the fund will mail you information about the tax status of the dividends and distributions paid to you by the fund.

------

**Tax information for IRA rollovers**

In January (or by the applicable Internal Revenue Service deadline) following the year in which you take a reportable distribution, the fund's transfer agent will mail you a tax form reflecting the total amount(s) of distribution(s) received by the end of January.

**Privacy**

The fund has a policy designed to protect the privacy of your personal information. A copy of Amundi US's privacy notice was given to you at the time you opened your account. The fund will send you a copy of the privacy notice each year. You may also obtain the privacy notice by calling the fund or through Amundi US's website.

**Signature guarantees and other requirements**

You are required to obtain a signature guarantee when:

• Requesting certain types of exchanges or sales of fund shares

• Requesting certain types of changes for your existing account

You can obtain a signature guarantee from most broker-dealers, banks, credit unions (if authorized under state law) and federal savings and loan associations. You cannot obtain a signature guarantee from a notary public.

The Pioneer funds generally accept only medallion signature guarantees. A medallion signature guarantee may be obtained from a domestic bank or trust company, broker, dealer, clearing agency, savings association, or other financial institution that is participating in a medallion program recognized by the Securities Transfer Association. Signature guarantees from financial institutions that are not participating in one of these programs are not accepted as medallion signature guarantees. The fund may accept other forms of guarantee from financial intermediaries in limited circumstances.

Fiduciaries and corporations are required to submit additional documents to sell fund shares.

**Minimum account size**

The fund requires that you maintain a minimum account value of $500. If you hold less than $500 in your account, the fund reserves the right to notify you that it intends to sell your shares and close your account. You will be given 60 days from the date of the notice to make additional investments to avoid having your shares sold. This policy does not apply to certain qualified retirement plan accounts.

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**Shareholder services and policies**

**Telephone and website access**

You may have difficulty contacting the fund by telephone or accessing amundi.com/us during times of market volatility or disruption in telephone or Internet service. On New York Stock Exchange holidays or on days when the exchange closes early, Amundi US will adjust the hours for the telephone center and for online transaction processing accordingly. If you are unable to access amundi.com/us or reach the fund by telephone, you should communicate with the fund in writing.

**Share certificates**

The fund does not offer share certificates. Shares are electronically recorded.

**Other policies**

The fund and the distributor reserve the right to:

• reject any purchase or exchange order for any reason, without prior notice

• charge a fee for exchanges or to modify, limit or suspend the exchange privilege at any time without notice. The fund will provide 60 days' notice of material amendments to or termination of the exchange privilege

• revise, suspend, limit or terminate the account options or services available to shareowners at any time, except as required by the rules of the Securities and Exchange Commission

The fund reserves the right to:

• charge transfer, shareholder servicing or similar agent fees, such as an account maintenance fee for small balance accounts, directly to accounts upon at least 30 days' notice. The fund may do this by deducting the fee from your distribution of dividends and/or by redeeming fund shares to the extent necessary to cover the fee

• close your account after a period of inactivity, as determined by state law, and transfer your shares to the appropriate state

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**Dividends, capital gains and taxes**

**Dividends and capital gains**

The fund declares dividends daily. The daily dividends consist of substantially all of the fund's net income (excluding any net short- and long-term capital gains). You begin to earn dividends on the first business day following receipt of payment for shares. You continue to earn dividends up to and including the date of sale. Dividends are normally paid on the last business day of each month.

The fund generally pays any distribution of net short- and long-term capital gains in November. The fund may also pay dividends and capital gain distributions at other times if necessary for the fund to avoid U.S. federal income or excise tax. If you invest in the fund shortly before a distribution described in this paragraph, generally you will pay a higher price per share and, unless you are exempt from tax, you will pay taxes on the amount of the distribution whether you reinvest the distribution in additional shares or receive it as cash.

**Taxes**

You will normally have to pay federal income taxes, and any state or local taxes, on the dividends and other distributions you receive from the fund, whether you take the distributions in cash or reinvest them in additional shares. For U.S. federal income tax purposes, distributions from the fund's net capital gains (if any) are considered long-term capital gains and are generally taxable to noncorporate shareholders at reduced rates. Distributions from the fund's net short-term capital gains are generally taxable as ordinary income. Other dividends are generally taxable as ordinary income. Since the fund's income is derived primarily from sources that do not pay dividends, it is not expected that a substantial portion of dividends paid by the fund will qualify either for the dividends-received deduction for corporations or for any favorable U.S. federal income tax rate available to noncorporate shareholders on "qualified dividend income."

The fund will report to shareholders annually the U.S. federal income tax status of all fund distributions.

If the fund declares a dividend in October, November or December, payable to shareholders of record in such a month, and pays it in January of the following year, you will be taxed on the dividend as if you received it in the year in which it was declared.

Sales and exchanges generally will be taxable transactions to shareowners. When you sell or exchange fund shares you will generally recognize a capital gain or capital loss in an amount equal to the difference between the net amount of sale proceeds (or, in the case of an exchange, the fair market value of the shares) that you receive and your tax basis for the shares that you sell or exchange.

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**Dividends, capital gains and taxes**

A 3.8% Medicare contribution tax generally applies to all or a portion of the net investment income of a shareholder who is an individual and not a nonresident alien for federal income tax purposes and who has adjusted gross income (subject to certain adjustments) that exceeds a threshold amount. This 3.8% tax also applies to all or a portion of the undistributed net investment income of certain shareholders that are estates and trusts. For these purposes, dividends, interest and certain capital gains are generally taken into account in computing a shareholder's net investment income.

You must provide your social security number or other taxpayer identification number to the fund along with the certifications required by the Internal Revenue Service when you open an account. If you do not or if it is otherwise legally required to do so, the fund will apply "backup withholding" tax on your dividends and other distributions, sale proceeds and any other payments to you that are subject to backup withholding. The backup withholding rate is currently 24%.

Shareholders that are exempt from U.S. federal income tax, such as retirement plans that are qualified under Section 401 of the Internal Revenue Code, generally are not subject to U.S. federal income tax on fund dividends or other distributions or on sales or exchanges of fund shares. However, in the case of fund shares held through a nonqualified deferred compensation plan, fund dividends and other distributions received by the plan and sales and exchanges of fund shares by the plan generally will be taxable to the employer sponsoring such plan in accordance with U.S. federal income tax laws that are generally applicable to shareholders receiving such dividends and other distributions from regulated investment companies such as the fund, or effecting such sales or exchanges.

Plan participants whose retirement plan invests in the fund generally are not subject to federal income tax on fund dividends or other distributions received by the plan or on sales or exchanges of fund shares by the plan. However, distributions to plan participants from a retirement plan generally are taxable to plan participants as ordinary income.

Distributions derived from interest on U.S. government obligations (but generally not distributions of gain from the sale of such obligations) may be exempt from certain state and local taxes.

You should ask your tax adviser about any federal, state, local and foreign tax considerations relating to an investment in the fund. You may also consult the fund's statement of additional information for a more detailed discussion of the U.S. federal income tax considerations that may affect the fund and its shareowners.

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**Financial highlights**

The financial highlights table helps you understand the fund's financial performance since the fund's inception.

Certain information reflects financial results for a single fund share. The total returns in the table represent the rate that you would have earned or lost on an investment in Class A, Class C or Class Y shares of the fund (assuming reinvestment of all dividends and distributions).

No financial information is presented for Class K shares because no Class K shares were outstanding during the most recent fiscal year.

The information below has been audited by Ernst & Young LLP, independent registered public accounting firm, whose report is included in the fund's annual report along with the fund's financial statements. The fund's annual report is incorporated by reference in the statement of additional information and is available upon request.

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**Financial highlights**

**Pioneer Floating Rate Fund** 

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year** <br>**Ended** <br>**10/31/22**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/21**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/20**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/19**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/18**<br>|
| **Class A** |  |  |  |  |  |
| Net asset value, beginning of period | $6.51 | $6.28 | $6.57 | $6.73 | $6.80 |
| Increase (decrease) from investment operations: |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp; Net investment income (loss) (a) | $0.26 | $0.19 | $0.21 | $0.31 | $0.26 |
| &nbsp;&nbsp;&nbsp; Net realized and unrealized gain (loss) on investments | &nbsp;&nbsp;&nbsp;&nbsp; (0.54) | &nbsp;&nbsp;&nbsp;&nbsp; 0.26 | &nbsp;&nbsp;&nbsp;&nbsp; (0.26) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (0.15) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (0.06) |
| **Net increase (decrease) from investment operations** | **$(0.28)** | **$0.45** | **$(0.05)** | **$0.16** | **$0.20** |
| Distributions to shareowners: |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp; Net investment income | $(0.23) | $(0.22) | $(0.24) | $(0.32) | $(0.27) |
| **Total distributions** | **$(0.23)** | **$(0.22)** | **$(0.24)** | **$(0.32)** | **$(0.27)** |
| **Net increase (decrease) in net asset value** | **$(0.51)** | **$0.23** | **$(0.29)** | **$(0.16)** | **$(0.07)** |
| Net asset value, end of period | $6.00 | $6.51 | $6.28 | $6.57 | $6.73 |
| **Total return (b)** | **(4.32)%** | **7.25%** | **(0.71)%** | **2.42%** | **2.96%** |
| Ratio of net expenses to average net assets | &nbsp;&nbsp;&nbsp;&nbsp; 1.05% | &nbsp;&nbsp;&nbsp;&nbsp; 1.05% | &nbsp;&nbsp;&nbsp;&nbsp; 1.12% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 1.07% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 1.01% |
| Ratio of net investment income (loss) to average net assets | &nbsp;&nbsp;&nbsp;&nbsp; 4.20% | &nbsp;&nbsp;&nbsp;&nbsp; 2.89% | &nbsp;&nbsp;&nbsp;&nbsp; 3.31% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 4.64% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 3.89% |
| Portfolio turnover rate | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 45% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 41% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 45% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 13% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 42% |
| Net assets, end of period (in thousands) | $84071 | $84417 | $69248 | $120559 | $161020 |
| &nbsp;&nbsp;&nbsp; Ratios with no waiver of fees and assumption of expenses by the Adviser <br> and no reduction for fees paid indirectly:<br>|  |  |  |  |  |
| &nbsp;&nbsp;&nbsp; Total expenses to average net assets | &nbsp;&nbsp;&nbsp;&nbsp; 1.22% | &nbsp;&nbsp;&nbsp;&nbsp; 1.26% | &nbsp;&nbsp;&nbsp;&nbsp; 1.17% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 1.11% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 1.01% |
| &nbsp;&nbsp;&nbsp; Net investment income (loss) to average net assets | &nbsp;&nbsp;&nbsp;&nbsp; 4.03% | &nbsp;&nbsp;&nbsp;&nbsp; 2.68% | &nbsp;&nbsp;&nbsp;&nbsp; 3.26% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 4.60% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 3.89% |

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;(a) The per-share data presented above is based on the average shares outstanding for the period presented.

&nbsp;&nbsp;&nbsp;&nbsp;(b) Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete
 redemption of the investment at net asset value at the end of each period and no sales charges. Total return would be reduced if sales charges
 were taken into account.

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**Pioneer Floating Rate Fund** 

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year** <br>**Ended** <br>**10/31/22**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/21**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/20**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/19**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/18**<br>|
| **Class C** |  |  |  |  |  |
| Net asset value, beginning of period | $6.57 | $6.34 | $6.57 | $6.74 | $6.80 |
| Increase (decrease) from investment operations: |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp; Net investment income (loss) (a) | $0.22 | $0.14 | $0.17 | $0.26 | $0.21 |
| &nbsp;&nbsp;&nbsp; Net realized and unrealized gain (loss) on investments | &nbsp;&nbsp;&nbsp;&nbsp; (0.55) | &nbsp;&nbsp;&nbsp;&nbsp; 0.26 | &nbsp;&nbsp;&nbsp;&nbsp; (0.21) | &nbsp;&nbsp;&nbsp;&nbsp; (0.16) | &nbsp;&nbsp;&nbsp;&nbsp; (0.05) |
| **Net increase (decrease) from investment operations** | **$(0.33)** | **$0.40** | **$(0.04)** | **$0.10** | **$0.16** |
| Distributions to shareowners: |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp; Net investment income | $(0.19) | $(0.17) | $(0.19) | $(0.27) | $(0.22) |
| **Total distributions** | **$(0.19)** | **$(0.17)** | **$(0.19)** | **$(0.27)** | **$(0.22)** |
| **Net increase (decrease) in net asset value** | **$(0.52)** | **$0.23** | **$(0.23)** | **$(0.17)** | **$(0.06)** |
| Net asset value, end of period | $6.05 | $6.57 | $6.34 | $6.57 | $6.74 |
| **Total return (b)** | **(5.11)%** | **6.39%** | **(0.54)%** | **1.52%** | **2.35%** |
| Ratio of net expenses to average net assets | &nbsp;&nbsp;&nbsp;&nbsp; 1.79% | &nbsp;&nbsp;&nbsp;&nbsp; 1.85% | &nbsp;&nbsp;&nbsp;&nbsp; 1.80% | &nbsp;&nbsp;&nbsp;&nbsp; 1.77% | &nbsp;&nbsp;&nbsp;&nbsp; 1.76% |
| Ratio of net investment income (loss) to average net assets | &nbsp;&nbsp;&nbsp;&nbsp; 3.42% | &nbsp;&nbsp;&nbsp;&nbsp; 2.12% | &nbsp;&nbsp;&nbsp;&nbsp; 2.63% | &nbsp;&nbsp;&nbsp;&nbsp; 3.94% | &nbsp;&nbsp;&nbsp;&nbsp; 3.15% |
| Portfolio turnover rate | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 45% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 41% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 45% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 13% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 42% |
| Net assets, end of period (in thousands) | $12520 | $14538 | $21352 | $39105 | $68364 |
| &nbsp;&nbsp;&nbsp; Ratios with no waiver of fees and assumption of expenses by the Adviser <br> and no reduction for fees paid indirectly:<br>|  |  |  |  |  |
| &nbsp;&nbsp;&nbsp; Total expenses to average net assets | &nbsp;&nbsp;&nbsp;&nbsp; 1.79% | &nbsp;&nbsp;&nbsp;&nbsp; 1.86% | &nbsp;&nbsp;&nbsp;&nbsp; 1.84% | &nbsp;&nbsp;&nbsp;&nbsp; 1.81% | &nbsp;&nbsp;&nbsp;&nbsp; 1.76% |
| &nbsp;&nbsp;&nbsp; Net investment income (loss) to average net assets | &nbsp;&nbsp;&nbsp;&nbsp; 3.42% | &nbsp;&nbsp;&nbsp;&nbsp; 2.11% | &nbsp;&nbsp;&nbsp;&nbsp; 2.59% | &nbsp;&nbsp;&nbsp;&nbsp; 3.90% | &nbsp;&nbsp;&nbsp;&nbsp; 3.15% |

---

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;(a) The per-share data presented above is based on the average shares outstanding for the period presented.

&nbsp;&nbsp;&nbsp;&nbsp;(b) Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete
 redemption of the investment at net asset value at the end of each period and no sales charges. Total return would be reduced if sales charges
 were taken into account.

------

**Financial highlights**

**Pioneer Floating Rate Fund** 

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year** <br>**Ended** <br>**10/31/22**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/21**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/20**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/19**<br>| &nbsp;&nbsp; **Year** <br>**Ended** <br>**10/31/18**<br>|
| **Class Y** |  |  |  |  |  |
| Net asset value, beginning of period | $6.58 | $6.34 | $6.59 | $6.75 | $6.82 |
| Increase (decrease) from investment operations: |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp; Net investment income (loss) (a) | $0.28 | $0.21 | $0.24 | $0.33 | $0.29 |
| &nbsp;&nbsp;&nbsp; Net realized and unrealized gain (loss) on investments | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (0.55) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.27 | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (0.22) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (0.15) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (0.07) |
| **Net increase (decrease) from investment operations** | **$(0.27)** | **$0.48** | **$0.02** | **$0.18** | **$0.22** |
| Distributions to shareowners: |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp; Net investment income | $(0.26) | $(0.24) | $(0.27) | $(0.34) | $(0.29) |
| **Total distributions** | **$(0.26)** | **$(0.24)** | **$(0.27)** | **$(0.34)** | **$(0.29)** |
| **Net increase (decrease) in net asset value** | **$(0.53)** | **$0.24** | **$(0.25)** | **$(0.16)** | **$(0.07)** |
| Net asset value, end of period | $6.05 | $6.58 | $6.34 | $6.59 | $6.75 |
| **Total return (b)** | **(4.25)%** | **7.70%** | **0.31%** | **2.74%** | **3.27%** |
| Ratio of net expenses to average net assets | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.75% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.75% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.71% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.70% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.70% |
| Ratio of net investment income (loss) to average net assets | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 4.39% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 3.16% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 3.71% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 5.00% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 4.22% |
| Portfolio turnover rate | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 45% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 41% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 45% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 13% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 42% |
| Net assets, end of period (in thousands) | $302184 | $366465 | $205324 | $336472 | $713216 |
| &nbsp;&nbsp;&nbsp; Ratios with no waiver of fees and assumption of expenses by the <br> Adviser and no reduction for fees paid indirectly:<br>|  |  |  |  |  |
| &nbsp;&nbsp;&nbsp; Total expenses to average net assets | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.82% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.81% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.86% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.85% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.77% |
| &nbsp;&nbsp;&nbsp; Net investment income (loss) to average net assets | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 4.32% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 3.10% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 3.56% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 4.85% | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 4.15% |

---

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;(a) The per-share data presented above is based on the average shares outstanding for the period presented.

&nbsp;&nbsp;&nbsp;&nbsp;(b) Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete
 redemption of the investment at net asset value at the end of each period and no sales charges. Total return would be reduced if sales charges
 were taken into account.

------

**Intermediary defined sales charge waiver policies**

The information below has been provided by the named financial intermediaries. Please contact the applicable financial intermediary with any questions regarding how it applies the policies described below and for assistance in determining whether you may qualify for a particular sales charge waiver or discount.

**Ameriprise Financial**

**Class A Shares Front-End Sales Charge Waivers Available at Ameriprise Financial:**

Effective January 15, 2021, the following information applies to Class A shares purchases if you have an account with or otherwise purchase Fund shares through Ameriprise Financial:

Shareholders purchasing Fund shares through an Ameriprise Financial brokerage account are eligible for the following front-end sales charge waivers, which may differ from those disclosed elsewhere in this Fund's prospectus or SAI:

• Employer-sponsored retirement plans (e.g., 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans). For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs or SAR-SEPs.

• Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same Fund (but not any other fund within the same fund family).

• Shares exchanged from Class C shares of the same fund in the month of or following the 7-year anniversary of the purchase date. To the extent that this prospectus elsewhere provides for a waiver with respect to exchanges of Class C shares or conversion of Class C shares following a shorter holding period, that waiver will apply.

• Employees and registered representatives of Ameriprise Financial or its affiliates and their immediate family members.

• Shares purchased by or through qualified accounts (including IRAs, Coverdell Education Savings Accounts, 401(k)s, 403(b) TSCAs subject to ERISA and defined benefit plans) that are held by a covered family member, defined as an Ameriprise financial advisor and/or the advisor's spouse, advisor's lineal ascendant (mother, father, grandmother, grandfather, great grandmother, great grandfather), advisor's lineal descendant (son, step-son, daughter, step-daughter, grandson, granddaughter, great grandson, great granddaughter) or any spouse of a covered family member who is a lineal descendant.

• Shares purchased from the proceeds of redemptions within the same fund family, provided (1) the repurchase occurs within 90 days following the redemption,

------

**Intermediary defined sales charge waiver policies**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;(2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales load (i.e. Rights of Reinstatement).

**Edward D. Jones & Co., L.P. ("Edward Jones")**

**Policies Regarding Transactions Through Edward Jones**

The following information has been provided by Edward Jones:

Effective on or after March 1, 2021, the following information supersedes prior information with respect to transactions and positions held in fund shares through an Edward Jones system. Clients of Edward Jones (also referred to as "shareholders") purchasing fund shares on the Edward Jones commission and fee-based platforms are eligible only for the following sales charge discounts (also referred to as "breakpoints") and waivers, which can differ from discounts and waivers described elsewhere in the mutual fund prospectus or statement of additional information ("SAI") or through another broker-dealer. In all instances, it is the shareholder's responsibility to inform Edward Jones at the time of purchase of any relationship, holdings of Pioneer Funds or other facts qualifying the purchaser for discounts or waivers. Edward Jones can ask for documentation of such circumstance. Shareholders should contact Edward Jones if they have questions regarding their eligibility for these discounts and waivers.

**Breakpoints**

• Breakpoint pricing, otherwise known as volume pricing, at dollar thresholds as described in the prospectus.

**Rights of Accumulation ("ROA")**

• The applicable sales charge on a purchase of Class A shares is determined by taking into account all share classes (except certain money market funds and any assets held in group retirement plans) of Pioneer Funds held by the shareholder or in an account grouped by Edward Jones with other accounts for the purpose of providing certain pricing considerations ("pricing groups"). If grouping assets as a shareholder, this includes all share classes held on the Edward Jones platform and/or held on another platform. The inclusion of eligible fund family assets in the ROA calculation is dependent on the shareholder notifying Edward Jones of such assets at the time of calculation. Money market funds are included only if such shares were sold with a sales charge at the time of purchase or acquired in exchange for shares purchased with a sales charge.

------

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• The employer maintaining a SEP IRA plan and/or SIMPLE IRA plan may elect to establish or change ROA for the IRA accounts associated with the plan to a plan-level grouping as opposed to including all share classes at a shareholder or pricing group level.

• ROA is determined by calculating the higher of cost minus redemptions or market value (current shares x NAV).

**Letter of Intent ("LOI")**

• Through a LOI, shareholders can receive the sales charge and breakpoint discounts for purchases shareholders intend to make over a 13-month period from the date Edward Jones receives the LOI. The LOI is determined by calculating the higher of cost or market value of qualifying holdings at LOI initiation in combination with the value that the shareholder intends to buy over a 13-month period to calculate the front-end sales charge and any breakpoint discounts. Each purchase the shareholder makes during that 13-month period will receive the sales charge and breakpoint discount that applies to the total amount. The inclusion of eligible fund family assets in the LOI calculation is dependent on the shareholder notifying Edward Jones of such assets at the time of calculation. Purchases made before the LOI is received by Edward Jones are not adjusted under the LOI and will not reduce the sales charge previously paid. Sales charges will be adjusted if LOI is not met.

• If the employer maintaining a SEP IRA plan and/or SIMPLE IRA plan has elected to establish or change ROA for the IRA accounts associated with the plan to a plan-level grouping, LOIs will also be at the plan-level and may only be established by the employer.

**Sales Charge Waivers**

Sales charges are waived for the following shareholders and in the following situations:

• Associates of Edward Jones and its affiliates and their family members who are in the same pricing group (as determined by Edward Jones under its policies and procedures) as the associate. This waiver will continue for the remainder of the associate's life if the associate retires from Edward Jones in good-standing and remains in good standing pursuant to Edward Jones' policies and procedures.

• Shares purchased in an Edward Jones fee-based program.

• Shares purchased through reinvestment of capital gains distributions and dividend reinvestment.

• Shares purchased from the proceeds of redeemed shares of the same fund family so long as the following conditions are met: 1) the proceeds are from the sale of

------

**Intermediary defined sales charge waiver policies**

shares within 60 days of the purchase, and 2) the sale and purchase are made in the same share class and the same account or the purchase is made in an individual retirement account with proceeds from liquidations in a non-retirement account.

• Shares exchanged into Class A shares from another share class so long as the exchange is into the same fund and was initiated at the discretion of Edward Jones. Edward Jones is responsible for any remaining CDSC due to the fund company, if applicable. Any future purchases are subject to the applicable sales charge as disclosed in the prospectus.

• Exchanges from Class C shares to Class A shares of the same fund, generally, in the 84<sup>th</sup> month following the anniversary of the purchase date or earlier at the discretion of Edward Jones.

**Contingent Deferred Sales Charge ("CDSC") Waivers**

If the shareholder purchases shares that are subject to a CDSC and those shares are redeemed before the CDSC is expired, the shareholder is responsible to pay the CDSC except in the following conditions:

• The death or disability of the shareholder.

• Systematic withdrawals with up to 10% per year of the account value.

• Return of excess contributions from an Individual Retirement Account (IRA).

• Shares sold as part of a required minimum distribution for IRA and retirement accounts if the redemption is taken in or after the year the shareholder reaches qualified age based on applicable IRS regulations.

• Shares sold to pay Edward Jones fees or costs in such cases where the transaction is initiated by Edward Jones.

• Shares exchanged in an Edward Jones fee-based program.

• Shares acquired through NAV reinstatement.

• Shares redeemed at the discretion of Edward Jones for Minimum Balances, as described below.

**Other Important Information Regarding Transactions Through Edward Jones**

**Minimum Purchase Amounts**

• Initial purchase minimum: $250

• Subsequent purchase minimum: none

**Minimum Balances**

• Edward Jones has the right to redeem at its discretion fund holdings with a balance of $250 or less. The following are examples of accounts that are not included in this policy:

-

A fee-based account held on an Edward Jones platform

------

-

A 529 account held on an Edward Jones platform

-

An account with an active systematic investment plan or LOI

**Exchanging Share Classes**

• At any time it deems necessary, Edward Jones has the authority to exchange at NAV a shareholder's holdings in a fund to Class A shares of the same fund.

**Janney Montgomery Scott**

Effective May 1, 2020, if you purchase fund shares through a Janney Montgomery Scott LLC ("Janney") brokerage account, you will be eligible for the following load waivers (front-end sales charge waivers and contingent deferred sales charge ("CDSC"), or back-end sales charge, waivers) and discounts, which may differ from those disclosed elsewhere in this fund's prospectus or statement of additional information.

**Front-end sales charge\* waivers on Class A shares available at Janney**

• Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other fund within the fund family).

• Shares purchased by employees and registered representatives of Janney or its affiliates and their family members as designated by Janney.

• Shares purchased from the proceeds of redemptions within the same fund family, provided (1) the repurchase occurs within ninety (90) days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales load (i.e., right of reinstatement).

• Employer-sponsored retirement plans (e.g., 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans). For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs, SAR-SEPs or Keogh plans.

• Shares acquired through a right of reinstatement.

• Class C shares that are no longer subject to a contingent deferred sales charge and are converted to Class A shares of the same fund pursuant to Janney's policies and procedures.

**CDSC waivers on Class A and C shares available at Janney**

• Shares sold upon the death or disability of the shareholder.

• Shares sold as part of a systematic withdrawal plan as described in the fund's prospectus.

• Shares purchased in connection with a return of excess contributions from an IRA account.

------

**Intermediary defined sales charge waiver policies**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• Shares sold as part of a required minimum distribution for IRA and retirement accounts if the redemption is taken in or after the year the shareholder reaches qualified age based on applicable IRS regulations

• Shares sold to pay Janney fees but only if the transaction is initiated by Janney.

• Shares acquired through a right of reinstatement.

• Shares exchanged into the same share class of a different fund.

**Front-end sales charge\* discounts available at Janney: breakpoints, rights of accumulation, and/or letters of intent**

• Breakpoints as described in the fund's prospectus.

• Rights of accumulation ("ROA"), which entitle shareholders to breakpoint discounts, will be automatically calculated based on the aggregated holding of fund family assets held by accounts within the purchaser's household at Janney. Eligible fund family assets not held at Janney may be included in the ROA calculation only if the shareholder notifies his or her financial advisor about such assets.

• Letters of intent which allow for breakpoint discounts based on anticipated purchases within a fund family, over a 13-month time period. Eligible fund family assets not held at Janney Montgomery Scott may be included in the calculation of letters of intent only if the shareholder notifies his or her financial advisor about such assets.

\*Also referred to as an "initial sales charge."

**Merrill Lynch**

The availability of certain sales charge waivers and discounts will depend on whether you purchase your shares directly from the fund or through a financial intermediary. Intermediaries may have different policies and procedures regarding the availability of front-end sales charge waivers or contingent deferred (back-end) sales charge ("CDSC") waivers, which are discussed below. In all instances, it is the purchaser's responsibility to notify the fund or the purchaser's financial intermediary at the time of purchase of any relationship or other facts qualifying the purchaser for sales charge waivers or discounts. For waivers and discounts not available through a particular intermediary, shareholders will have to purchase fund shares directly from the fund or through another intermediary to receive these waivers or discounts.

Shareholders purchasing fund shares through a Merrill Lynch platform or account will be eligible only for the following sales charge waivers (front-end sales charge waivers and contingent deferred or back-end, sales charge waivers) and discounts, which may differ from those disclosed elsewhere in this fund's prospectus or statement of additional information.

------

**Front-End Sales Charge Waivers on Class A Shares available at Merrill Lynch**

• Employer-sponsored retirement, deferred compensation and employee benefit plans (including health savings accounts) and trusts used to fund those plans, provided that the shares are not held in a commission-based brokerage account and shares are held for the benefit of the plan

• Shares purchased by a 529 Plan (does not include 529 Plan units or 529-specific share classes or equivalents)

• Shares purchased through a Merrill Lynch affiliated investment advisory program

• Shares exchanged due to the holdings moving from a Merrill Lynch affiliated investment advisory program to a Merrill Lynch brokerage (non-advisory) account pursuant to Merrill Lynch's policies relating to sales charge discounts and waivers

• Shares purchased by third party investment advisors on behalf of their advisory clients through Merrill Lynch's platform

• Shares of funds purchased through the Merrill Edge Self-Directed platform (if applicable)

• Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other fund within the fund family)

• Shares exchanged from Class C (i.e. level-load) shares of the same fund pursuant to Merrill Lynch's policies relating to sales charge discounts and waivers

• Employees and registered representatives of Merrill Lynch or its affiliates and their family members

• Directors or Trustees of the fund, and employees of the fund's investment adviser or any of its affiliates, as described in this prospectus

• Eligible shares purchased from the proceeds of redemptions within the same fund family, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales charge (known as Rights of Reinstatement). Automated transactions (i.e. systematic purchases and withdrawals) and purchases made after shares are automatically sold to pay Merrill Lynch's account maintenance fees are not eligible for reinstatement.

**CDSC Waivers on Class A and C Shares available at Merrill Lynch**

• Death or disability of the shareholder

• Shares sold as part of a systematic withdrawal plan as described in the fund's prospectus

• Return of excess contributions from an IRA Account

• Shares sold as part of a required minimum distribution for IRA and retirement accounts pursuant to the Internal Revenue Code

------

**Intermediary defined sales charge waiver policies**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• Shares sold to pay Merrill Lynch fees but only if the transaction is initiated by Merrill Lynch

• Shares acquired through a right of reinstatement

• Shares held in retirement brokerage accounts, that are exchanged for a lower cost share class due to transfer to certain fee based accounts or platforms (applicable to Class A and C shares only)

• Shares received through an exchange due to the holdings moving from a Merrill Lynch affiliated investment advisory program to a Merrill Lynch brokerage (non-advisory) account pursuant to Merrill Lynch's policies relating to sales charge discounts and waivers

**Front-End Sales Charge Discounts available at Merrill Lynch: Breakpoints, Rights of Accumulation and Letters of Intent**

• Breakpoints as described in this prospectus

• Rights of Accumulation (ROA), which entitle shareholders to breakpoint discounts as described in the fund's prospectus will be automatically calculated based on the aggregated holding of fund family assets held by accounts (including 529 program holdings, where applicable) within the purchaser's household at Merrill Lynch. Eligible fund family assets not held at Merrill Lynch may be included in the ROA calculation only if the shareholder notifies his or her financial advisor about such assets

• Letters of Intent (LOI) which allow for breakpoint discounts based on anticipated purchases within a fund family, through Merrill Lynch, over a 13-month period of time (if applicable)

**Morgan Stanley** 

Effective July 1, 2018, shareholders purchasing fund shares through a Morgan Stanley Wealth Management transactional brokerage account will be eligible only for the following front-end sales charge waivers with respect to Class A shares, which may differ from and may be more limited than those disclosed elsewhere in this fund's prospectus or statement of additional information.

**Front-end Sales Charge Waivers on Class A Shares available at Morgan Stanley Wealth Management**

• Employer-sponsored retirement plans (e.g., 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans). For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs, SAR-SEPs or Keogh plans

• Morgan Stanley employee and employee-related accounts according to Morgan Stanley's account linking rules

------

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• Shares purchased through reinvestment of dividends and capital gains distributions when purchasing shares of the same fund

• Shares purchased through a Morgan Stanley self-directed brokerage account

• Class C (i.e., level-load) shares that are no longer subject to a contingent deferred sales charge and are converted to Class A shares of the same fund pursuant to Morgan Stanley Wealth Management's share class conversion program

• Shares purchased from the proceeds of redemptions within the same fund family, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales charge.

**Oppenheimer & Co. Inc. ("OPCO")**

Shareholders purchasing fund shares through an OPCO platform or account are eligible only for the following load waivers (front-end sales charge waivers and contingent deferred or back-end, sales charge waivers) and discounts, which may differ from those disclosed elsewhere in this fund's prospectus or statement of additional information.

**Front-end Sales Load Waivers on Class A Shares available at OPCO**

• Employer-sponsored retirement, deferred compensation and employee benefit plans (including health savings accounts) and trusts used to fund those plans, provided that the shares are not held in a commission-based brokerage account and shares are held for the benefit of the plan

• Shares purchased by or through a 529 Plan

• Shares purchased through an OPCO affiliated investment advisory program

• Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other fund within the fund family)

• Shares purchased form the proceeds of redemptions within the same fund family, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same amount, and (3) redeemed shares were subject to a front-end or deferred sales load (known as Rights of Restatement).

• A shareholder in the fund's Class C shares will have their shares converted at net asset value to Class A shares (or the appropriate share class) of the fund if the shares are no longer subject to a CDSC and the conversion is in line with the policies and procedures of OPCO

• Employees and registered representatives of OPCO or its affiliates and their family members

• Directors or Trustees of the fund, and employees of the fund's investment adviser or any of its affiliates, as described in this prospectus

------

**Intermediary defined sales charge waiver policies**

**CDSC Waivers on A, B and C Shares available at OPCO**

• Death or disability of the shareholder

• Shares sold as part of a systematic withdrawal plan as described in the fund's prospectus

• Return of excess contributions from an IRA Account

• Shares sold as part of a required minimum distribution for IRA and retirement accounts due to the shareholder reaching age 70½ as described in the prospectus

• Shares sold to pay OPCO fees but only if the transaction is initiated by OPCO

• Shares acquired through a right of reinstatement

**Front-end load Discounts Available at OPCO: Breakpoints, Rights of Accumulation & Letters of Intent**

• Breakpoints as described in this prospectus.

• Rights of Accumulation (ROA), which entitle shareholders to breakpoint discounts, will be automatically calculated based on the aggregated holding of fund family assets held by accounts within the purchaser's household at OPCO. Eligible fund family assets not held at OPCO may be included in the ROA calculation only if the shareholder notifies his or her financial advisor about such assets

**Raymond James**

**Raymond James & Associates, Inc., Raymond James Financial Services, Inc., and each entity's affiliates ("Raymond James")**

Effective March 1, 2019, shareholders purchasing fund shares through a Raymond James platform or account, or through an introducing broker-dealer or independent registered investment adviser for which Raymond James provides trade execution, clearance, and/or custody services, will be eligible only for the following load waivers (front-end sales charge waivers and contingent deferred, or back-end, sales charge waivers) and discounts, which may differ from those disclosed elsewhere in this fund's prospectus or SAI.

**Front-end sales load waivers on Class A shares available at Raymond James**

• Shares purchased in an investment advisory program.

• Shares purchased within the same fund family through a systematic reinvestment of capital gains and dividend distributions.

• Employees and registered representatives of Raymond James or its affiliates and their family members as designated by Raymond James.

• Shares purchased from the proceeds of redemptions within the same fund family, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales load (known as rights of reinstatement).

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• A shareholder in the fund's Class C shares will have their shares converted at net asset value to Class A shares (or the appropriate share class) of the fund if the shares are no longer subject to a CDSC and the conversion is in line with the policies and procedures of Raymond James.

**CDSC Waivers on Class A and Class C shares available at Raymond James**

• Death or disability of the shareholder.

• Shares sold as part of a systematic withdrawal plan as described in the fund's prospectus.

• Return of excess contributions from an IRA Account.

• Shares sold as part of a required minimum distribution for IRA and retirement accounts due to the shareholder reaching the qualified age based on applicable IRS regulations as described in the fund's prospectus.

• Shares sold to pay Raymond James fees but only if the transaction is initiated by Raymond James.

• Shares acquired through a right of reinstatement.

**Front-end load discounts available at Raymond James: breakpoints, rights of accumulation and/or letters of intent**

• Breakpoints as described in this prospectus.

• Rights of accumulation which entitle shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of fund family assets held by accounts within the purchaser's household at Raymond James. Eligible fund family assets not held at Raymond James may be included in the calculation of rights of accumulation calculation only if the shareholder notifies his or her financial advisor about such assets.

• Letters of intent which allow for breakpoint discounts based on anticipated purchases within a fund family, over a 13-month time period. Eligible fund family assets not held at Raymond James may be included in the calculation of letters of intent only if the shareholder notifies his or her financial advisor about such assets.

**Robert W. Baird & Co. ("Baird"):**

Effective June 15, 2020, shareholders purchasing fund shares through a Baird platform or account will only be eligible for the following sales charge waivers (front-end sales charge waivers and CDSC waivers) and discounts, which may differ from those disclosed elsewhere in this prospectus or the SAI.

**Front-End Sales Charge Waivers on Investors A shares Available at Baird**

• Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing share of the same fund

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**Intermediary defined sales charge waiver policies**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• Share purchase by employees and registers representatives of Baird or its affiliate and their family members as designated by Baird

• Shares purchased using the proceeds of redemptions from a Pioneer Fund, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same accounts, and (3) redeemed shares were subject to a front-end or deferred sales charge (known as rights of reinstatement)

• A shareholder in the funds Investor C Shares will have their share converted at net asset value to Investor A shares of the same fund if the shares are no longer subject to CDSC and the conversion is in line with the policies and procedures of Baird

• Employer-sponsored retirement plans or charitable accounts in a transactional brokerage account at Baird, including 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans. For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs or SAR-SEPs

**CDSC Waivers on Investor A and C shares Available at Baird**

• Shares sold due to death or disability of the shareholder

• Shares sold as part of a systematic withdrawal plan as described in the fund's prospectus

• Shares bought due to returns of excess contributions from an IRA Account

• Shares sold as part of a required minimum distribution for IRA and retirement accounts due to the shareholder reaching the qualified age based on applicable Internal Revenue Service regulations as described in the fund's prospectus

• Shares sold to pay Baird fees but only if the transaction is initiated by Baird

• Shares acquired through a right of reinstatement

**Front-End Sales Charge Discounts Available at Baird: Breakpoints and/or Rights of Accumulations**

• Breakpoints as described in this prospectus

• Rights of accumulations which entitles shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of Pioneer assets held by accounts within the purchaser's household at Baird. Eligible Pioneer assets not held at Baird may be included in the rights of accumulations calculation only if the shareholder notifies his or her financial advisor about such assets

• Letters of Intent (LOI) allow for breakpoint discounts based on anticipated purchases of Pioneer through Baird, over a 13-month period of time

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**Waivers Specific to Stifel, Nicolaus & Company, Incorporated ("Stifel")**

Effective July 1, 2020, shareholders purchasing fund shares through a Stifel platform or account or who own shares for which Stifel or an affiliate is the broker-dealer of record are eligible for the following additional sales charge waiver.

**Front-end Sales Load Waiver on Class A Shares** 

• Class C shares that have been held for more than seven (7) years will be converted to Class A shares of the same fund pursuant to Stifel's policies and procedures

All other sales charge waivers and reductions described elsewhere in the fund's prospectus or statement of additional information still apply.

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Notes

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Notes

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Notes

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**Pioneer Floating Rate Fund**

**You can obtain more free information** about the fund from your investment firm or by writing to Pioneer Funds, 60 State Street, Boston, Massachusetts 02109. You may also call **1-800-225-6292** for more information about the fund, to request copies of the fund's statement of additional information and shareowner reports, and to make other inquiries.

**Visit our website**

amundi.com/us

The fund makes available the statement of additional information and shareowner reports, free of charge, on the fund's website at amundi.com/us. You also may find other information and updates about Amundi US and the fund, including fund performance information and the fund's most recent net asset value, on the fund's website.

**Shareowner reports**

Annual and semiannual reports to shareowners, and quarterly reports filed with the Securities and Exchange Commission, provide additional information about the fund's investments. The annual report discusses market conditions and investment strategies that significantly affected the fund's performance during its last fiscal year.

**Statement of additional information**

The statement of additional information provides more detailed information about the fund.

The statement of additional information, dated March 1, 2023, as may be amended from time to time, and filed with the Securities and Exchange Commission, is incorporated by reference into this prospectus.

The fund's shareowner reports, prospectus and statement of additional information are available on the Securities and Exchange Commission's EDGAR database on the Commission's Internet site at https://www.sec.gov. Copies of this information may be obtained, after paying a duplicating fee, by electronic request at the following e-mail address: publicinfo@sec.gov.

(Investment Company Act file no. 811-21978)

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| Amundi Distributor US, Inc.<br> 60 State Street<br> Boston, MA 02109<br> **amundi.com/us**<br>| 20451-22-0323<br>©2023 Amundi Distributor US, Inc.<br> Member SIPC<br>|

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![](backcover_new2021.jpg)

Amundi Asset Management US, Inc. <br>60 State Street <br>Boston, MA 02109 <br>**amundi.com/us**

This is not part of the prospectus.

20451-22-0323 <br>©2023 Amundi Distributor US, Inc. <br>Underwriter of Pioneer mutual funds <br>Member SIPC

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