OMB APPROVAL OMB Number: 3235-0570 Expires: January 31, 2017 Estimated average burden hours per response.....20.6 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM N-CSR CERTIFIED SHAREHOLDER REPORT OF REGISTERED MANAGEMENT INVESTMENT COMPANIES 		Investment Company Act file number 811-21978 Pioneer Series Trust VI (Exact name of registrant as specified in charter) 60 State Street, Boston, MA 02109 (Address of principal executive offices) (ZIP code) Terrence J. Cullen, Pioneer Investment Management, Inc., 60 State Street, Boston, MA 02109 (Name and address of agent for service) Registrant's telephone number, including area code: (617) 742-7825 Date of fiscal year end: October 31 Date of reporting period: November 1, 2014 through October 31, 2015 Form N-CSR is to be used by management investment companies to file reports with the Commission not later than 10 days after the transmission to stockholders of any report that is required to be transmitted to stockholders under Rule 30e-1 under the Investment Company Act of 1940 (17 CFR 270.30e-1). The Commission may use the information provided on Form N-CSR in its regulatory, disclosure review, inspection, and policymaking roles. A registrant is required to disclose the information specified by Form N-CSR, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-CSR unless the Form displays a currently valid Office of Management and Budget ("OMB") control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to Secretary, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0609. The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. ss. 3507. ITEM 1. REPORTS TO STOCKHOLDERS. Pioneer Floating Rate Fund -------------------------------------------------------------------------------- Annual Report | October 31, 2015 -------------------------------------------------------------------------------- Ticker Symbols: Class A FLARX Class C FLRCX Class K FLRKX Class Y FLYRX [LOGO] PIONEER Investments(R) visit us: us.pioneerinvestments.com Table of Contents President's Letter 2 Portfolio Management Discussion 4 Portfolio Summary 8 Prices and Distributions 9 Performance Update 10 Comparing Ongoing Fund Expenses 14 Schedule of Investments 16 Financial Statements 44 Notes to Financial Statements 52 Report of Independent Registered Public Accounting Firm 64 Approval of Investment Advisory Agreement 66 Trustees, Officers and Service Providers 71 Pioneer Floating Rate Fund | Annual Report | 10/31/15 1 President's Letter Dear Shareholder, Through the first three quarters of 2015, global markets experienced pockets of higher-than-average volatility due to significant cross-currents from different geographic regions. All year, investors focused on the Federal Reserve System's (the Fed's) deliberations over when to begin normalizing interest rates. However, while there were signs of gradual economic improvement in the U.S., economies abroad increasingly diverged. In June, for example, investors grew concerned about the debt crisis in Greece. That news, in turn, was followed by evidence of an economic slowdown in China, which only served to exacerbate existing worries about growth trends in the emerging markets, a segment of the global economy already being negatively impacted by slumping commodity prices, including the price of crude oil, which has been in near-steady decline for almost a year. Through September 30, 2015, the pockets of height ened market volatility alluded to above had resulted in the Standard & Poor's 500 Index turning in a negative (-5.27%) return over the first nine months of the year. However, the S&P 500 recovered nicely in October, returning 8.43% for the month, which boosted the index's year-to-date return into positive territory, at 2.71%. Despite the headwinds still vexing the global economy, our longer-term view of the U.S. economy has remained positive. Economic conditions in the U.S. have generally been constructive, based largely on improvements in employment statistics and an uptick in the housing sector, which has aided the consumer side of the economy, where household spending has been rising modestly. U.S. consumers also stand to benefit, potentially, from lower energy prices as the winter weather approaches. We continue to believe the U.S. economy remains on a slow, steady growth trend, and that it is unlikely to be disrupted by a slow pace of interest-rate normalization by the Fed. Pioneer Investments believes that investors in today's environment can potentially benefit from the consistent and disciplined investment approach we have used since our founding in 1928. We focus on identifying value across global markets using proprietary research, careful risk management, and a long-term perspective. Our ongoing goal is to produce compelling returns consistent with the stated objectives of our investment products, and with our shareowners' expectations. We believe our shareowners can benefit from the experience and tenure of our investment teams as well as the insights generated from our extensive research process. 2 Pioneer Floating Rate Fund | Annual Report | 10/31/15 As always, and particularly during times of market uncertainty, we encourage you to work with your financial advisor to develop an overall investment plan that addresses both your short- and long-term goals, and to implement such a plan in a disciplined manner. We greatly appreciate your trust in us in the past and look forward to continuing to serve you in the future. Sincerely, /s/ Lisa M. Jones Lisa M. Jones President and CEO Pioneer Investment Management USA Inc. November 2, 2015 Any information in this shareowner report regarding market or economic trends or the factors influencing the Fund's historical or future performance are statements of opinion as of the date of this report. These statements should not be relied upon for any other purposes. Past performance is no guarantee of future results, and there is no guarantee that market forecasts discussed will be realized. Pioneer Floating Rate Fund | Annual Report | 10/31/15 3 Portfolio Management Discussion | 10/31/15 Floating-rate bank loans produced modest investment returns during the 12-month period ended October 31, 2015, as investors' confidence in the economy early in the period gave way to worries about slowing global growth trends. In the following interview, Jonathan Sharkey discusses the factors that influenced the performance of Pioneer Floating Rate Fund during the 12-month period. Mr. Sharkey, a senior vice president and a portfolio manager at Pioneer, is responsible for the day-to-day management of the Fund. Q How did the Fund perform during the 12-month period ended October 31, 2015? A Pioneer Floating Rate Fund's Class A shares returned 1.53% at net asset value during the 12-month period ended October 31, 2015, while the Fund's benchmark, the Barclays High Yield Loans Performing Index (the Barclays Index), returned 1.29%. During the same period, the average return of the 209 mutual funds in Lipper's Loan Participating Funds category was -0.01%, and the average return of the 249 mutual funds in Morningstar's Bank Loan Funds category was -0.02%. Q How would you describe the investment environment for bank loans during the 12-month period ended October 31, 2015? A Conflicting forces hit the bank loan market during the period. For a total of six months, the market environment was positive, while the backdrop was more negative during the other six months. November and December of 2014, the first two months of the period, foreshadowed the up-and-down market conditions during the Fund's entire fiscal year. Bank loans turned in positive performance in November, followed by a negative return for December, as the effects of falling oil prices on energy-related loans acted as a drag on the market. During the first five months of 2015, from January 1 through May 31, bank loans performed positively as market demand for loan investments increased based on a number of factors. They included investors' general confidence in the health of the domestic economy, the credit-worthiness of bank loans, and the perception that interest rates eventually would increase, which would benefit floating-rate loan investments. That supportive backdrop deteriorated, however, beginning in June, as a series of developments combined to erode the confidence of market participants. Some of the issues causing investors' concerns included a renewed debt crisis in Greece, further declines in crude oil prices, and the slowing of economic growth in China. All of those factors contributed to negative market sentiment, and June 1 through October 31 marked the fourth-worst five-month performance period in the history of bank loan investments. Despite the slump between June and October, as of 4 Pioneer Floating Rate Fund | Annual Report | 10/31/15 period end, the year-to-date performance of bank loans, as measured by the Barclays Index, remained in positive territory. Moreover, the asset class had outperformed both high-yield and investment-grade securities over the first 10 months of 2015. Q What were the principal factors that affected the Fund's performance relative to the Barclays Index benchmark during the 12-month period ended October 31, 2015? A The Fund slightly outperformed the Barclays Index during the 12-month period, for several reasons. Primarily, the Fund's positive benchmark- relative results benefited the most from our emphasis on holding higher-quality loans than the Barclays Index; from the portfolio's below- benchmark exposures to the poorer-performing energy sector; and from overall favorable security selection results. With regard to quality, during the period we maintained consistently lower Fund exposures, compared with the benchmark, to loans rated B- or CCC. That up-in-quality bias aided relative returns. At the same time, the Fund's allocation to struggling energy sector loans was just over 3% of invested assets, lower than that of the benchmark. In addition, the Fund had a relatively small exposure to loans in the metals and mining industry, which also underperformed during the 12-month period. With regard to individual portfolio investments, the holding that contributed the most to the Fund's benchmark-relative returns during the period was a loan to Virtual Radiological, a corporation that provides remote diagnostic imaging services to health care providers. The company had been experiencing some financial difficulties, but the debt recovered in value when the corporation was sold. Other portfolio positions that performed well and helped the Fund's relative results included loans to Ocwen Financial, Apex Tool, and DelMonte Foods. While the Fund had relatively good selection results in the underperforming energy and metals and mining groups, the 10 investments that detracted the most from performance on an absolute return basis all came from those two areas. In energy, the portfolio's underperforming holdings included loans to Paragon Offshore, Ocean Rig and Pacific Drilling. In metals and mining, holdings that detracted from Fund performance included loans to Essar Steel and Fortescue Resources, an Australian mining company. Also holding back the Fund's results, on a benchmark-relative basis, was an investment in loans to Weight Watchers International. We substantially reduced the Fund's position in Weight Watchers' loans and moved to an underweight during the 12-month period. Unfortunately, the reduction Pioneer Floating Rate Fund | Annual Report | 10/31/15 5 came prior to the announcement that media personality Oprah Winfrey was acquiring a major stake in the company, which led to a sharp recovery in the prices of the loans. Q Did the Fund have any exposure to derivative securities during the 12-month period ended October 31, 2015? If so, did the positions affect the Fund's performance? A Yes, the Fund held one credit default swap position during the period, which was sold well before period end. The position had little to no impact on the Fund's performance. Q What factors affected the Fund's yield, or distributions to shareholders, during the 12-month period ended October 31, 2015? A The Fund's dividend* modestly declined during the fiscal year ended October 31st. Yields paid by higher-rated loans, such as those held in the Fund's portfolio, tended to drift lower over the 12 months, as those loans saw strong demand during a period when the market's appetite for lower-rated loans tended to decline. Given the increased demand for the higher-quality loans, there was little pressure for yields to increase. Q What is your investment outlook? A Recent job-creation data, which remains solid, combined with a relatively low unemployment rate - now hovering at around 5% - increases the likelihood that the U.S. Federal Reserve System (the Fed) could start raising short-term interest rates perhaps as soon as the end of 2015, or early in 2016. Any increase in short-term interest rates likely will have a favorable impact on both the yields and prices of floating-rate bank loans, although the effects may not be immediately felt. Bank loans recently have been trading at discounted prices that, in our opinion, overstate both current and likely future default risks, and so we believe loans continue to offer attractive investment value. We also think floating-rate bank loans represent a good relative value compared with traditional income-oriented, longer-duration investment alternatives, such as bonds. If market interest rates, like the rate on 10-year Treasuries, start to rise, we think longer-duration bond funds will experience price pressures, while the floating-rate feature of bank loans, on the other hand, can provide some price protection. (Duration is a measure of the sensitivity of the price, or the value of principal, of a fixed-income investment to a change in interest rates, expressed as a number of years). * Dividends are not guaranteed. 6 Pioneer Floating Rate Fund | Annual Report | 10/31/15 Overall, we believe floating-rate bank loans represent a good investment opportunity for appropriate investors, and that prospects for the loan market should improve even more once market interest rates begin to rise. From that point, the key risk going forward would be any macroeconomic event that might make the Fed hit the "pause button" on any further rate increases, or any regulatory issue that disrupts future CLO issuance, as CLOs have been a market-stabilizing investor in the bank-loan asset class over the past two years. Please refer to the Schedule of Investments on pages 16-43 for a full listing of Fund securities. 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-rated debt securities. The Fund may invest in high-yield securities of any rating, including securities that are in default at the time of purchase. 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. 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. Investing in foreign and/or emerging markets securities involves risks relating to interest rates, currency exchange rates, economic, and political conditions. These risks may increase share price volatility. Before investing, consider the product's investment objectives, risks, charges and expenses. Contact your advisor or Pioneer Investments for a prospectus or summary prospectus containing this information. Read it carefully. Any information in this shareholder report regarding market or economic trends or the factors influencing the Fund's historical or future performance are statements of opinion as of the date of this report. Past performance is no guarantee of future results. Pioneer Floating Rate Fund | Annual Report | 10/31/15 7 Portfolio Summary | 10/31/15 Portfolio Diversification* -------------------------------------------------------------------------------- (As a percentage of total investment portfolio) [THE FOLLOWING DATA WAS REPRESENTED AS A PIE CHART IN THE PRINTED MATERIAL] Senior Secured Loans 93.1% International Corporate Bonds 1.9% U.S. Government Securities 1.5% U.S. Corporate Bonds 1.4% Temporary Cash Investment 1.0% Asset Backed Securities 0.5% U.S. Preferred Stocks 0.2% Exchange Traded Fund 0.2% U.S. Common Stocks 0.1% Collateralized Mortgage Obligations 0.1% Convertible Preferred Stocks 0.0%+ + Amount rounds to less than 0.1%. * Includes investments in Insurance Linked Securities totaling 1.4% of total investment portfolio. 10 Largest Holdings -------------------------------------------------------------------------------- (As a percentage of long-term holdings)** 1. Charter Communications Operating LLC, Term F Loan, 1/1/21 0.84% -------------------------------------------------------------------------------- 2. U.S. Treasury Note, Floating Rate Note, 4/30/17 0.79 -------------------------------------------------------------------------------- 3. U.S. Treasury Note, Floating Rate Note, 1/31/17 0.79 -------------------------------------------------------------------------------- 4. Albertsons LLC, Term B-2 Loan, 3/21/19 0.77 -------------------------------------------------------------------------------- 5. CityCenter Holdings LLC, Term B Loan, 10/16/20 0.73 -------------------------------------------------------------------------------- 6. American Airlines, Inc., 2015 Term Loan, 6/27/20 0.70 -------------------------------------------------------------------------------- 7. PQ Corp., 2014 Term Loan, 8/7/17 0.62 -------------------------------------------------------------------------------- 8. Avago Technologies Ltd., Tranche B Term Loan (First Lien), 4/16/21 0.61 -------------------------------------------------------------------------------- 9. Tower Automotive Holdings USA LLC, Initial Term Loan (2014), 4/23/20 0.59 -------------------------------------------------------------------------------- 10. CSM Bakery Solutions LLC, Term Loan (First Lien), 7/3/20 0.59 -------------------------------------------------------------------------------- ** This list excludes temporary cash investments and derivative instruments. The portfolio is actively managed, and current holdings may be different. The holdings listed should not be considered recommendations to buy or sell any security listed. 8 Pioneer Floating Rate Fund | Annual Report | 10/31/15 Prices and Distributions | 10/31/15 Net Asset Value per Share -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- Class 10/31/15 10/31/14 -------------------------------------------------------------------------------- A $6.73 $6.86 -------------------------------------------------------------------------------- C $6.74 $6.87 -------------------------------------------------------------------------------- K $6.73 $6.86 -------------------------------------------------------------------------------- Y $6.75 $6.88 -------------------------------------------------------------------------------- Distributions per Share: 11/1/14-10/31/15 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- Net Investment Short-Term Long-Term Class Income Capital Gains Capital Gains -------------------------------------------------------------------------------- A $0.2342 $ -- $ -- -------------------------------------------------------------------------------- C $0.1856 $ -- $ -- -------------------------------------------------------------------------------- K $0.2604 $ -- $ -- -------------------------------------------------------------------------------- Y $0.2605 $ -- $ -- -------------------------------------------------------------------------------- The Barclays High Yield Loans Performing Index is an unmanaged index that provides broad and comprehensive total return metrics of the universe of syndicated term loans. To be included in the index, a bank loan must be dollar denominated, have at least $150 million in funded loans, a minimum term of one year, and a minimum initial spread of LIBOR+1.25%. Index returns are calculated monthly, assume reinvestment of dividends and, unlike Fund returns, do not reflect any fees, expenses or sales charges. It is not possible to invest directly in an index. The index defined here pertains to the "Value of $10,000 Investment" and "Value of $5 Million Investment" charts on pages 10-13. Pioneer Floating Rate Fund | Annual Report | 10/31/15 9 Performance Update | 10/31/15 Class A Shares Investment Returns -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Class A shares of Pioneer Floating Rate Fund at public offering price during the periods shown, compared to that of the Barclays High Yield Loans Performing Index. Cumulative Total Returns (As of October 31, 2015) -------------------------------------------------------------------------------- Net Public Barclays High Asset Offering Yield Loans Value Price Performing Period (NAV) (POP) Index -------------------------------------------------------------------------------- Life of Class (2/14/2007) 3.50% 2.96% 4.26% 5 Years 3.65 2.71 4.25 1 Year 1.53 -2.99 1.29 -------------------------------------------------------------------------------- Expense Ratio (Per prospectus dated March 1, 2015) -------------------------------------------------------------------------------- Gross -------------------------------------------------------------------------------- 1.07% -------------------------------------------------------------------------------- [THE FOLLOWING DATA WAS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL] Value of $10,000 Investment Pioneer Floating Barclays High Yield Loans Rate Fund Performing Index 2/07 $ 9,550 $10,000 10/07 $ 9,670 $10,162 10/08 $ 7,972 $ 7,945 10/09 $ 9,845 $10,540 10/10 $10,774 $11,751 10/11 $11,095 $12,080 10/12 $11,919 $13,155 10/13 $12,424 $13,898 10/14 $12,694 $14,361 10/15 $12,889 $14,436 Call 1-800-225-6292 or visit us.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. POP returns reflect deduction of maximum 4.50% sales charge. NAV results represent the percent change in net asset value per share. Returns would have been lower had sales charges been reflected. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. 10 Pioneer Floating Rate Fund | Annual Report | 10/31/15 Performance Update | 10/31/15 Class C Shares Investment Returns -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Class C shares of Pioneer Floating Rate Fund during the periods shown, compared to that of the Barclays High Yield Loans Performing Index. Cumulative Total Returns (As of October 31, 2015) -------------------------------------------------------------------------------- Barclays High Yield Loans If If Performing Period Held Redeemed Index -------------------------------------------------------------------------------- Life of Class (2/14/2007) 2.69% 2.69% 4.26% 5 Years 2.91 2.91 4.25 1 Year 0.81 0.81 1.29 -------------------------------------------------------------------------------- Expense Ratio (Per prospectus dated March 1, 2015) -------------------------------------------------------------------------------- Gross -------------------------------------------------------------------------------- 1.78% -------------------------------------------------------------------------------- [THE FOLLOWING DATA WAS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL] Value of $10,000 Investment Pioneer Floating Barclays High Yield Loans Rate Fund Performing Index 2/07 $10,000 $10,000 10/07 $10,070 $10,162 10/08 $ 8,211 $ 7,945 10/09 $10,069 $10,540 10/10 $10,921 $11,751 10/11 $11,176 $12,080 10/12 $11,898 $13,155 10/13 $12,327 $13,898 10/14 $12,503 $14,361 10/15 $12,605 $14,436 Call 1-800-225-6292 or visit us.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. Class C shares held for less than one year are also subject to a 1% contingent deferred sales charge (CDSC). "If Held" results represent the percent change in net asset value per share. Returns would have been lower had sales charges been reflected. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. Pioneer Floating Rate Fund | Annual Report | 10/31/15 11 Performance Update | 10/31/15 Class K Shares Investment Returns -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Class K shares of Pioneer Floating Rate Fund during the periods shown, compared to that of the Barclays High Yield Loans Performing Index. Cumulative Total Returns (As of October 31, 2015) -------------------------------------------------------------------------------- Net Barclays High Asset Yield Loans Value Performing Period (NAV) Index -------------------------------------------------------------------------------- Life of Fund (2/14/2007) 3.59% 4.26% 5 Years 3.81 4.25 1 Year 1.92 1.29 -------------------------------------------------------------------------------- Expense Ratio (Per prospectus dated March 1, 2015) -------------------------------------------------------------------------------- Gross -------------------------------------------------------------------------------- 0.69% -------------------------------------------------------------------------------- [THE FOLLOWING DATA WAS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL] Value of $10,000 Investment Pioneer Floating Barclays High Yield Loans Rate Fund Performing Index 2/07 $10,000 $10,000 10/07 $10,121 $10,162 10/08 $ 8,344 $ 7,945 10/09 $10,304 $10,540 10/10 $11,277 $11,751 10/11 $11,613 $12,080 10/12 $12,475 $13,155 10/13 $13,004 $13,898 10/14 $13,339 $14,361 10/15 $13,595 $14,436 Call 1-800-225-6292 or visit us.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. The performance shown for Class K shares for the period prior to the commencement of operations of Class K shares on December 10, 2013, is the net asset value performance of the Fund's Class A shares, which has not been restated to reflect any differences in expenses, including Rule 12b-1 fees applicable to Class A shares. Since fees for Class A shares generally are higher than those of Class K shares, the performance of Class K shares prior to their inception would have been higher than the performance shown. For the period beginning December 10, 2013, the actual performance of Class K shares is reflected. Class K shares are not subject to sales charges and are available for limited groups of eligible investors, including institutional investors. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. 12 Pioneer Floating Rate Fund | Annual Report | 10/31/15 Performance Update | 10/31/15 Class Y Shares Investment Returns -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $5 million investment made in Class Y shares of Pioneer Floating Rate Fund during the periods shown, compared to that of the Barclays High Yield Loans Performing Index. Cumulative Total Returns (As of October 31, 2015) -------------------------------------------------------------------------------- Net Barclays High Asset Yield Loans Value Performing Period (NAV) Index -------------------------------------------------------------------------------- Life of Class (2/14/2007) 3.75% 4.26% 5 Years 3.99 4.25 1 Year 1.92 1.29 -------------------------------------------------------------------------------- Expense Ratio (Per prospectus dated March 1, 2015) -------------------------------------------------------------------------------- Gross Net -------------------------------------------------------------------------------- 0.82% 0.70% -------------------------------------------------------------------------------- [THE FOLLOWING DATA WAS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL] Value of $5 Million Investment Pioneer Floating Barclays High Yield Loans Rate Fund Performing Index 2/07 $5,000,000 $5,000,000 10/07 $5,061,980 $5,080,852 10/08 $4,174,504 $3,972,310 10/09 $5,163,652 $5,270,050 10/10 $5,665,295 $5,875,608 10/11 $5,841,313 $6,039,967 10/12 $6,295,679 $6,577,577 10/13 $6,595,680 $6,948,991 10/14 $6,760,856 $7,180,379 10/15 $6,890,708 $7,218,025 Call 1-800-225-6292 or visit us.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. Class Y shares are not subject to sales charges and are available for limited groups of eligible investors, including institutional investors. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The net expense ratio reflects the contractual expense limitation currently in effect through March 1, 2016, for Class Y shares. There can be no assurance that Pioneer will extend the expense limitation beyond such time. Please see the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. Pioneer Floating Rate Fund | Annual Report | 10/31/15 13 Comparing Ongoing Fund Expenses As a shareowner in the Fund, you incur two types of costs: (1) ongoing costs, including management fees, distribution and/or service (12b-1) fees, and other Fund expenses; and (2) transaction costs, including sales charges (loads) on purchase payments. This example is intended to help you understand your ongoing expenses (in dollars) of investing in the Fund and to compare these costs with the ongoing costs of investing in other mutual funds. The example is based on an investment of $1,000 at the beginning of the Fund's latest six-month period and held throughout the six months. Using the Tables -------------------------------------------------------------------------------- Actual Expenses The first table below provides information about actual account values and actual expenses. You may use the information in this table, together with the amount you invested, to estimate the expenses that you paid over the period as follows: (1) Divide your account value by $1,000 Example: an $8,600 account value (divided by) $1,000 = 8.6 (2) Multiply the result in (1) above by the corresponding share class's number in the third row under the heading entitled "Expenses Paid During Period" to estimate the expenses you paid on your account during this period. Expenses Paid on a $1,000 Investment in Pioneer Floating Rate Fund Based on actual returns from May 1, 2015, through October 31, 2015. -------------------------------------------------------------------------------- Share Class A C K Y -------------------------------------------------------------------------------- Beginning Account $1,000.00 $1,000.00 $1,000.00 $1,000.00 Value on 5/1/15 -------------------------------------------------------------------------------- Ending Account $ 996.96 $ 993.59 $ 997.65 $ 999.22 Value (after expenses) on 10/31/15 -------------------------------------------------------------------------------- Expenses Paid $ 5.44 $ 9.10 $ 3.57 $ 3.53 During Period* -------------------------------------------------------------------------------- * Expenses are equal to the Fund's annualized expense ratio of 1.08%, 1.81%, 0.71% and 0.70% for class A, C, K and Y shares, respectively, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period). 14 Pioneer Floating Rate Fund | Annual Report | 10/31/15 Hypothetical Example for Comparison Purposes The table below provides information about hypothetical account values and hypothetical expenses based on the Fund's actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the Fund's actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period. You may use this information to compare the ongoing costs of investing in the Fund and other funds. To do so, compare this 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of the other funds. Please note that the expenses shown in the tables are meant to highlight your ongoing costs only and do not reflect any transaction costs, such as sales charges (loads) that are charged at the time of the transaction. Therefore, the table below is useful in comparing ongoing costs only and will not help you determine the relative total costs of owning different funds. In addition, if these transaction costs were included, your costs would have been higher. Expenses Paid on a $1,000 Investment in Pioneer Floating Rate Fund Based on a hypothetical 5% return per year before expenses, reflecting the period from May 1, 2015, through October 31, 2015. -------------------------------------------------------------------------------- Share Class A C K Y -------------------------------------------------------------------------------- Beginning Account $1,000.00 $1,000.00 $1,000.00 $1,000.00 Value on 5/1/15 -------------------------------------------------------------------------------- Ending Account $1,019.76 $1,016.08 $1,021.63 $1,021.68 Value (after expenses) on 10/31/15 -------------------------------------------------------------------------------- Expenses Paid $ 5.50 $ 9.20 $ 3.62 $ 3.57 During Period* -------------------------------------------------------------------------------- * Expenses are equal to the Fund's annualized expense ratio of 1.08%, 1.81%, 0.71% and 0.70% for class A, C, K and Y shares, respectively, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period). Pioneer Floating Rate Fund | Annual Report | 10/31/15 15 Schedule of Investments | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- PREFERRED STOCKS -- 0.3% BANKS -- 0.1% Diversified Banks -- 0.1% 18,434 7.88 Citigroup Capital XIII, Floating Rate Note, 10/30/40 $ 468,224 1,567 6.00 US Bancorp, Floating Rate Note (Perpetual) 41,996 ------------- $ 510,220 ------------- Total Banks $ 510,220 -------------------------------------------------------------------------------------------------- DIVERSIFIED FINANCIALS -- 0.2% Consumer Finance -- 0.2% 40,000 8.12 GMAC Capital Trust I, Floating Rate Note, 2/15/40 $ 1,033,200 ------------- Total Diversified Financials $ 1,033,200 -------------------------------------------------------------------------------------------------- TOTAL PREFERRED STOCKS (Cost $1,608,754) $ 1,543,420 -------------------------------------------------------------------------------------------------- CONVERTIBLE PREFERRED STOCKS -- 0.0%+ CAPITAL GOODS -- 0.0%+ Industrial Machinery -- 0.0%+ 1,000 Stanley Black & Decker, Inc., 4.75%, 11/17/15 $ 145,250 ------------- Total Capital Goods $ 145,250 -------------------------------------------------------------------------------------------------- TOTAL CONVERTIBLE PREFERRED STOCKS (Cost $100,000) $ 145,250 -------------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------- Shares -------------------------------------------------------------------------------------------------- COMMON STOCKS -- 0.1% COMMERCIAL SERVICES & SUPPLIES -- 0.0%+ Diversified Support Services -- 0.0%+ 32 IAP Worldwide Services, Inc. $ 44,589 ------------- Total Commercial Services & Supplies $ 44,589 -------------------------------------------------------------------------------------------------- AUTOMOBILES & COMPONENTS -- 0.0%+ Auto Parts & Equipment -- 0.0%+ 50 Lear Corp. $ 6,253 ------------- Total Automobiles & Components $ 6,253 -------------------------------------------------------------------------------------------------- CONSUMER SERVICES -- 0.1% Education Services -- 0.1% 26,266 Cengage Learning Holdings II, Inc. $ 636,950 ------------- Total Consumer Services $ 636,950 -------------------------------------------------------------------------------------------------- TOTAL COMMON STOCKS (Cost $1,031,142) $ 687,792 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 16 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- ASSET BACKED SECURITIES -- 0.1% BANKS -- 0.1% Thrifts & Mortgage Finance -- 0.1% 500,000 1.77 KKR Financial CLO 2007-1, Ltd., Floating Rate Note, 5/15/21 (144A) $ 498,078 ------------- Total Banks $ 498,078 -------------------------------------------------------------------------------------------------- DIVERSIFIED FINANCIALS -- 0.0%+ Specialized Finance -- 0.0%+ 253,854 0.63 Lease Investment Flight Trust, Floating Rate Note, 7/15/31 $ 139,620 253,854 0.59 Lease Investment Flight Trust, Floating Rate Note, 7/15/31 121,850 ------------- $ 261,470 ------------- Total Diversified Financials $ 261,470 -------------------------------------------------------------------------------------------------- TOTAL ASSET BACKED SECURITIES (Cost $839,135) $ 759,548 -------------------------------------------------------------------------------------------------- COLLATERALIZED MORTGAGE OBLIGATIONS -- 0.1% DIVERSIFIED FINANCIALS -- 0.1% Other Diversified Financial Services -- 0.1% 373,586 4.19 Velocity Commercial Capital Loan Trust 2011-1, Floating Rate Note, 8/25/40 (144A) $ 358,643 ------------- Total Diversified Financials $ 358,643 -------------------------------------------------------------------------------------------------- TOTAL COLLATERALIZED MORTGAGE OBLIGATIONS (Cost $331,443) $ 358,643 -------------------------------------------------------------------------------------------------- CORPORATE BONDS -- 3.2% ENERGY -- 0.4% Oil & Gas Drilling -- 0.0%+ 100,000 7.50 Offshore Group Investment, Ltd., 7.5%, 11/1/19 (e) $ 29,375 -------------------------------------------------------------------------------------------------- Oil & Gas Exploration & Production -- 0.1% 800,000 WPX Energy, Inc., 7.5%, 8/1/20 $ 748,000 -------------------------------------------------------------------------------------------------- Oil & Gas Storage & Transportation -- 0.3% 1,405,000 NuStar Logistics LP, 6.75%, 2/1/21 $ 1,461,200 ------------- Total Energy $ 2,238,575 -------------------------------------------------------------------------------------------------- MATERIALS -- 0.3% Specialty Chemicals -- 0.1% 900,000 INEOS Group Holdings SA, 5.875%, 2/15/19 (144A) $ 900,000 -------------------------------------------------------------------------------------------------- Construction Materials -- 0.1% 350,000 Cemex SAB de CV, 5.875%, 3/25/19 (144A) $ 353,850 -------------------------------------------------------------------------------------------------- Paper Products -- 0.1% 795,000 Resolute Forest Products, Inc., 5.875%, 5/15/23 $ 592,275 ------------- Total Materials $ 1,846,125 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 17 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- CAPITAL GOODS -- 0.1% Construction & Engineering -- 0.1% 750,000 MasTec, Inc., 4.875%, 3/15/23 $ 628,125 -------------------------------------------------------------------------------------------------- Electrical Components & Equipment -- 0.0%+ 250,000 WireCo WorldGroup, Inc., 9.5%, 5/15/17 $ 227,500 ------------- Total Capital Goods $ 855,625 -------------------------------------------------------------------------------------------------- CONSUMER DURABLES & APPAREL -- 0.1% Homebuilding -- 0.1% 335,000 Brookfield Residential Properties, Inc., 6.125%, 7/1/22 (144A) $ 329,138 ------------- Total Consumer Durables & Apparel $ 329,138 -------------------------------------------------------------------------------------------------- MEDIA -- 0.3% Advertising -- 0.1% 770,000 MDC Partners, Inc., 6.75%, 4/1/20 (144A) $ 783,475 -------------------------------------------------------------------------------------------------- Broadcasting -- 0.1% 210,000 0.83 NBCUniversal Enterprise, Inc., Floating Rate Note, 4/15/16 (144A) $ 210,236 -------------------------------------------------------------------------------------------------- Cable & Satellite -- 0.1% 540,000 Virgin Media Secured Finance Plc, 5.375%, 4/15/21 (144A) $ 567,000 ------------- Total Media $ 1,560,711 -------------------------------------------------------------------------------------------------- RETAILING -- 0.1% Specialty Stores -- 0.1% 660,000 Outerwall, Inc., 6.0%, 3/15/19 $ 656,700 ------------- Total Retailing $ 656,700 -------------------------------------------------------------------------------------------------- FOOD, BEVERAGE & TOBACCO -- 0.0%+ Packaged Foods & Meats -- 0.0%+ 229,000 Chiquita Brands International, Inc., 7.875%, 2/1/21 $ 243,026 ------------- Total Food, Beverage & Tobacco $ 243,026 -------------------------------------------------------------------------------------------------- BANKS -- 0.1% Diversified Banks -- 0.1% 500,000 1.10 Bank of America Corp., Floating Rate Note, 3/22/16 $ 500,848 180,000 5.95 Citigroup, Inc., Floating Rate Note (Perpetual) 178,650 ------------- $ 679,498 ------------- Total Banks $ 679,498 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 18 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- DIVERSIFIED FINANCIALS -- 0.1% Specialized Finance -- 0.1% 615,000 Nationstar Mortgage LLC, 6.5%, 8/1/18 $ 603,469 ------------- Total Diversified Financials $ 603,469 -------------------------------------------------------------------------------------------------- INSURANCE -- 1.3% Reinsurance -- 1.3% 500,000 5.95 Alamo Re, Ltd., Floating Rate Note, 6/7/18 (Cat Bond) (144A) $ 519,100 500,000 3.52 Atlas IX Capital, Ltd., Floating Rate Note, 1/17/19 (Cat Bond) (144A) 508,600 250,000 8.33 Atlas Reinsurance VII, Ltd., Floating Rate Note, 1/7/16 (Cat Bond) (144A) 252,225 500,000 4.37 Blue Danube II, Ltd., Floating Rate Note, 5/23/16 (Cat Bond) (144A) 497,450 250,000 6.86 Caelus Re, Ltd., Floating Rate Note, 4/7/17 (Cat Bond) (144A) 258,025 250,000 0.00 Compass Re II, Ltd., Floating Rate Note, 6/8/16 (Cat Bond) 249,050 250,000 9.06 East Lane Re V, Ltd., Floating Rate Note, 3/16/16 (Cat Bond) (144A) 255,925 548,100 Exeter Segregated Account (Kane SAC Ltd.), Variable Rate Notes, 1/7/16 (f) 596,223 650,000 4.77 Kilimanjaro Re, Ltd., Floating Rate Note, 4/30/18 (Cat Bond) (144A) 650,975 350,000 4.27 Longpoint Re, Ltd. III, Floating Rate Note, 5/18/16 (Cat Bond) (144A) 352,415 500,000 7.27 Northshore Re, Ltd., Floating Rate Note, 7/5/16 (Cat Bond) (144A) 512,150 500,000 0.00 PennUnion Re, Ltd., Floating Rate Note, 12/7/18 (Cat Bond) (144A) 500,600 600,000 8.60 Queen Street VII Re, Ltd., Floating Rate Note, 4/8/16 (Cat Bond) (144A) 601,320 350,000 10.03 Residential Reinsurance 2012, Ltd., Floating Rate Note, 6/6/16 (Cat Bond) (144A) 365,540 250,000 9.28 Residential Reinsurance 2013, Ltd., Floating Rate Note, 6/6/17 (Cat Bond) (144A) 264,625 500,000 3.51 Sanders Re, Ltd., Floating Rate Note, 5/5/17 (Cat Bond) (144A) 499,550 500,000 3.87 Sanders Re, Ltd., Floating Rate Note, 6/7/17 (Cat Bond) (144A) 506,200 250,000 11.32 Successor X, Ltd., Floating Rate Note, 11/10/15 (Cat Bond) (144A) 250,125 250,000 8.49 Tar Heel Re, Ltd., Floating Rate Note, 5/9/16 (Cat Bond) (144A) 257,450 ------------- $ 7,897,548 ------------- Total Insurance $ 7,897,548 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 19 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- SEMICONDUCTORS & SEMICONDUCTOR EQUIPMENT -- 0.1% Semiconductors -- 0.1% 750,000 Micron Technology, Inc., 5.25%, 8/1/23 (144A) $ 732,742 ------------- Total Semiconductors & Semiconductor Equipment $ 732,742 -------------------------------------------------------------------------------------------------- TELECOMMUNICATION SERVICES -- 0.1% Wireless Telecommunication Services -- 0.1% 550,000 0.66 Vodafone Group Plc, Floating Rate Note, 2/19/16 $ 549,744 ------------- Total Telecommunication Services $ 549,744 -------------------------------------------------------------------------------------------------- UTILITIES -- 0.2% Gas Utilities -- 0.0%+ 250,000 Ferrellgas LP, 6.5%, 5/1/21 $ 231,875 -------------------------------------------------------------------------------------------------- Independent Power Producers & Energy Traders -- 0.2% 521,000 NRG Energy, Inc., 6.25%, 7/15/22 $ 479,320 375,000 Star Energy Geothermal Wayang Windu, Ltd., 6.125%, 3/27/20 (144A) 364,688 ------------- $ 844,008 ------------- Total Utilities $ 1,075,883 -------------------------------------------------------------------------------------------------- TOTAL CORPORATE BONDS (Cost $19,890,116) $ 19,268,784 -------------------------------------------------------------------------------------------------- U.S. GOVERNMENT AND AGENCY OBLIGATIONS -- 1.5% 4,445,000 0.10 U.S. Treasury Note, Floating Rate Note, 1/31/17 $ 4,444,280 ------------- 4,450,000 0.09 U.S. Treasury Note, Floating Rate Note, 4/30/17 4,447,552 -------------------------------------------------------------------------------------------------- TOTAL U.S. GOVERNMENT AND AGENCY OBLIGATIONS (Cost $8,896,659) $ 8,891,832 -------------------------------------------------------------------------------------------------- SENIOR FLOATING RATE LOAN INTERESTS -- 88.6%** ENERGY -- 3.6% Oil & Gas Drilling -- 0.8% 2,992,091 6.00 Drillships Financing Holding, Inc., Tranche B-1 Term Loan, 3/31/21 (g) $ 1,742,893 1,750,000 7.50 Jonah Energy LLC, Term Loan (Second Lien), 5/8/21 1,378,125 346,110 5.75 Offshore Group Investment, Ltd., Term Loan, 3/28/19 (e) (g) 103,256 1,208,040 4.50 Pacific Drilling SA, Term Loan, 6/3/18 (g) 665,428 1,980,000 3.75 Paragon Offshore Finance, Term Loan, 7/16/21 (g) 782,100 ------------- $ 4,671,802 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 20 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Oil & Gas Equipment & Services -- 0.8% 691,250 3.75 77 Energy, Tranche B Loan (First Lien), 6/17/21 $ 578,346 1,770,509 3.88 Fieldwood Energy LLC, Closing Date Loan, 9/25/18 1,571,327 1,670,250 5.75 FR Dixie Acquisition Corp., Term Loan, 1/23/21 1,252,688 1,012,188 5.25 McDermott International, Inc., Tranche B Loan (First Lien), 4/11/19 994,474 ------------- $ 4,396,835 -------------------------------------------------------------------------------------------------- Integrated Oil & Gas -- 0.6% 1,634,277 5.25 ExGen Renewables I LLC, Term Loan, 2/5/21 $ 1,646,534 214,073 4.50 Glenn Pool Oil & Gas Trust, Term Loan, 5/2/16 213,538 1,350,938 4.00 Seadrill Operating LP, Initial Term Loan, 2/14/21 794,351 997,500 5.00 TerraForm AP Acquisition Holdings LLC, Term Loan, 6/26/22 977,550 ------------- $ 3,631,973 -------------------------------------------------------------------------------------------------- Oil & Gas Exploration & Production -- 0.6% 1,650,000 3.50 EP Energy LLC, Tranche B-3 Loan, 5/24/18 $ 1,492,219 943,314 0.00 Penn Products Terminals, LLC Tranche B Term Loan, 4/1/22 (d) 947,441 1,355,936 5.50 TPF II Power, LLC, Term Loan, 10/2/21 1,356,275 ------------- $ 3,795,935 -------------------------------------------------------------------------------------------------- Oil & Gas Refining & Marketing -- 0.7% 1,516,005 4.25 Chelsea Petroleum Products I LLC, Term B Loan 7/22/22 $ 1,503,372 936,059 0.00 Pilot Travel Centers LLC, Initial Tranche B Term Loan, 10/30/21 (d) 941,521 1,768,500 4.25 Western Refining, Inc., Term Loan 2013, 11/12/20 1,739,024 ------------- $ 4,183,917 -------------------------------------------------------------------------------------------------- Oil & Gas Storage & Transportation -- 0.1% 464,706 0.00 Energy Transfer Equity, First Lien Term Loan, 12/2/19 (d) $ 452,023 -------------------------------------------------------------------------------------------------- Coal & Consumable Fuels -- 0.0%+ 195,833 18.15 Bumi Resources Tbk PT, Term Loan, 11/7/15 $ 63,646 ------------- Total Energy $ 21,196,131 -------------------------------------------------------------------------------------------------- MATERIALS -- 9.5% Commodity Chemicals -- 0.6% 1,247,489 4.50 AZ Chem US, Inc., Tranche B Term Loan (First Lien), 6/9/21 $ 1,248,113 2,406,120 4.25 Tronox Pigments Holland BV, New Term Loan, 3/19/20 2,219,215 ------------- $ 3,467,328 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 21 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Diversified Chemicals -- 0.9% 498,750 0.00 Chemours Company, Tranche B Term Loan, 5/12/22 (d) $ 455,525 2,125,180 5.00 Nexeo Solutions LLC, Initial Term Loan, 2/26/17 2,045,486 948,120 4.25 OXEA Sarl, Tranche B-2 Term Loan (First Lien), 1/15/20 912,566 1,995,595 3.75 Tata Chemicals North America, Inc., Term Loan, 8/7/20 1,982,707 ------------- $ 5,396,284 -------------------------------------------------------------------------------------------------- Fertilizers & Agricultural Chemicals -- 0.2% 997,500 4.25 Methanol Holdings Limited, Initial Term Loan, 6/2/22 $ 950,119 -------------------------------------------------------------------------------------------------- Specialty Chemicals -- 2.7% 1,740,064 4.50 Allnex Luxembourg & CY SCA, Tranche B-1 Term Loan, 10/4/19 $ 1,743,871 902,835 4.50 Allnex Luxembourg & CY SCA, Tranche B-2 Term Loan, 10/4/19 904,811 2,311,981 3.75 Axalta Coating Systems US Holdings, Inc., Refinanced Term B Loan, 2/1/20 2,309,091 321,135 3.50 Chemtura Corp., New Term Loan, 8/29/16 320,867 851,023 3.26 Huntsman International LLC, 2015 Extended Term B Dollar Loan, 4/19/19 843,045 2,688,125 4.50 MacDermid, Inc., Tranche B Term Loan (First Lien), 6/7/20 2,607,481 2,002,637 4.25 OMNOVA Solutions, Inc., Term B-1 Loan, 5/31/18 1,987,617 3,502,462 4.00 PQ Corp., 2014 Term Loan, 8/7/17 3,497,538 529,141 2.75 WR Grace & Co-Conn, Delayed Draw Term Loan, 1/23/21 521,535 1,470,399 2.75 WR Grace & Co-Conn, U.S. Term Loan, 1/23/21 1,449,262 ------------- $ 16,185,118 -------------------------------------------------------------------------------------------------- Construction Materials -- 0.3% 1,509,642 4.25 CeramTec Service GmbH, Initial Dollar Term B-1 Loan, 8/30/20 $ 1,512,001 -------------------------------------------------------------------------------------------------- Metal & Glass Containers -- 0.5% 311,260 4.00 Ardagh Holdings USA, Inc., Tranche B-3 Term Loan (First Lien), 12/17/19 $ 312,087 997,475 5.50 BWay Intermediate, Initial Term Loan, 8/14/20 1,000,592 1,000,000 5.00 Prolampac Holdings, Inc., Initial Term Loan (First Lien), 7/23/22 996,250 948,750 4.50 Tekni-Plex, Inc., Tranche B-1 Term Loan (First Lien), 4/15/22 945,785 ------------- $ 3,254,714 -------------------------------------------------------------------------------------------------- Paper Packaging -- 1.0% 2,500,000 4.00 Berry Plastics Corporation, Term F Loan, 9/17/22 $ 2,507,640 1,326,705 8.00 Caraustar Industries, Inc., Term Loan, 5/1/19 1,327,258 404,627 4.50 Coveris Holdings SA, USD Term Loan, 4/14/19 404,375 The accompanying notes are an integral part of these financial statements. 22 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Paper Packaging (continued) 1,797,313 4.25 Multi Packaging Solutions, Inc., Initial Dollar Tranche B Term, 9/30/20 $ 1,789,450 ------------- $ 6,028,723 -------------------------------------------------------------------------------------------------- Aluminum -- 0.6% 265,375 5.75 Noranda Aluminum Acquisition Corp., Term B Loan, 2/28/19 $ 170,503 1,496,250 0.00 Novelis, Inc., Initial Term Loan, 5/28/22 (d) 1,467,610 2,063,250 5.50 TurboCombustor Technology, Inc., Initial Term Loan, 10/18/20 1,991,036 ------------- $ 3,629,149 -------------------------------------------------------------------------------------------------- Diversified Metals & Mining -- 0.9% 3,130,180 3.75 Fortescue Metals Group Ltd., Bank Loan, 6/30/19 $ 2,659,870 2,969,450 4.00 US Silica Co., Term Loan, 7/23/20 2,791,283 ------------- $ 5,451,153 -------------------------------------------------------------------------------------------------- Steel -- 1.3% 1,705,200 3.50 American Builders & Contractors Supply Co, Inc., Term B Loan, 4/16/20 $ 1,697,740 992,438 4.50 Atkore International, Inc., Term Loan (First Lien), 3/27/21 935,372 960,300 7.50 Essar Steel Algoma Inc., Initial Term Loan, 8/9/19 529,365 1,715,954 4.75 JMC Steel Group, Inc., Term Loan, 4/1/17 1,673,055 1,052,593 3.75 Signode Industrial Group US, Inc., Tranche B Term Loan (First Lien), 3/21/21 1,037,681 1,696,905 4.50 TMS International Corp., Term B Loan, 10/2/20 1,620,544 ------------- $ 7,493,757 -------------------------------------------------------------------------------------------------- Paper Products -- 0.5% 1,653,881 5.75 Appvion, Inc., Term Commitment, 6/28/19 $ 1,567,052 1,232,881 4.25 Rack Holdings, Inc., Tranche B-1 USD Term Loan, 10/1/21 1,229,028 ------------- $ 2,796,080 ------------- Total Materials $ 56,164,426 -------------------------------------------------------------------------------------------------- CAPITAL GOODS -- 8.8% Aerospace & Defense -- 2.2% 2,519,570 4.00 Accudyne Industries Borrower SCA, Refinancing Term Loan, 12/13/19 $ 2,322,205 1,246,875 0.00 Alion Science and Technology Corporation, Term Loan (First Lien), 8/13/21 (d) 1,240,121 947,816 4.25 CPI International, Inc., Term B Loan, 11/17/17 947,816 2,723,402 3.75 DigitalGlobe, Inc., Term Loan, 1/25/20 2,727,640 1,864,216 6.25 DynCorp International, Inc., Term Loan, 7/7/16 1,817,610 438,728 0.00 Standard Aero Limited, First Lien Term Loan, 6/23/22 (d) 438,180 1,258,263 7.00 TASC, Inc., First Lien Term Loan, 2/28/17 1,262,982 The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 23 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Aerospace & Defense (continued) 1,685,342 5.75 The SI Organization, Inc., Term Loan (First Lien), 11/19/19 $ 1,680,603 623,685 3.25 Wesco Aircraft Hardare Corp., Tranche B Term Loan (First Lien), 2/24/21 610,951 ------------- $ 13,048,108 -------------------------------------------------------------------------------------------------- Building Products -- 3.2% 2,462,975 3.50 Armstrong World Industries, Inc., Term Loan B, 3/15/20 $ 2,458,869 2,250,000 6.00 Builders FirstSource, Inc., Initial Term Loan, 7/24/22 2,241,914 1,628,921 4.25 NCI Building Systems, Inc., Tranche B Term Loan, 6/24/19 1,626,376 1,675,806 0.00 Nortek, Inc., Incremental-1 Loan, 10/30/20 (d) 1,659,048 2,300,000 6.25 Quanex Building Products Corporation, Term Loan First Lien, 10/7/22 2,272,688 2,750,955 4.00 Quikrete Holdings, Inc., Initial Loan (First Lien), 9/26/20 2,747,506 1,221,938 0.00 Summit Materials, LLC, Restatement Effective Date Term Loan, 6/26/22 (d) 1,221,556 2,652,750 5.50 Ultima Intermediate Sarl, Term Loan B (First Lien), 7/2/20 2,675,962 2,089,925 4.25 Unifrax Corp., New Term B Loan, 12/31/19 2,073,379 ------------- $ 18,977,298 -------------------------------------------------------------------------------------------------- Construction & Engineering -- 0.1% 361,605 3.75 Aecom Technology, Term Loan B, 10/15/21 $ 363,729 -------------------------------------------------------------------------------------------------- Electrical Components & Equipment -- 0.9% 617,064 5.25 Pelican Products, Inc., Term Loan (First Lien), 4/8/20 $ 614,364 2,967,468 3.00 Southwire Co., Term Loan, 1/31/21 2,952,631 1,926,019 6.00 WireCo WorldGroup, Inc., Term Loan, 2/15/17 1,923,611 ------------- $ 5,490,606 -------------------------------------------------------------------------------------------------- Industrial Conglomerates -- 0.7% 155,188 4.25 CeramTec Acquisition Corp., Initial Dollar Term B-2 Loan, 8/30/20 $ 155,431 456,909 4.25 CeramTec GmbH, Dollar Term B-3 Loan, 8/30/20 457,623 1,252,043 4.50 Doosan Infracore, Tranche B Term, 5/28/21 1,256,216 700,000 5.00 Filtration Group Corporation, Term Loan (First Lien), 11/21/20 700,525 742,500 4.25 Gates Global LLC, Tranche B Term Loan (First Lien), 6/12/21 700,425 403,363 5.00 Kloeckner Pentaplast of America, Inc., Initial U.S. Borrower Dollar Term Loan, 4/22/20 404,372 The accompanying notes are an integral part of these financial statements. 24 Pioneer Floating Rate Fund | Annual Report | 10/31/15 ----------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value ----------------------------------------------------------------------------------------------------- Industrial Conglomerates (continued) 172,378 5.00 KP Germany Erste GmbH, Initial German Borrower Dollar Term Loan, 4/22/20 $ 172,808 ------------- $ 3,847,400 ----------------------------------------------------------------------------------------------------- Construction & Farm Machinery & Heavy Trucks -- 0.2% 299,088 3.25 Manitowoc Co. Inc. (The), Term B Loan, 12/18/20 $ 288,799 1,185,000 6.50 Navistar, Inc., Tranche B Term Loan, 8/17/17 1,150,931 ------------- $ 1,439,730 ----------------------------------------------------------------------------------------------------- Industrial Machinery -- 1.1% 2,334,208 4.25 Gardner Denver, Inc., Initial Dollar Term Loan, 7/30/20 $ 2,194,480 2,000,000 0.00 NN, Inc.Initial Term Loan, 10/2/22 (d) 1,995,000 1,217,199 5.25 Tank Holding Corp., Initial Term Loan, 7/9/19 1,210,505 1,378,298 6.25 Xerium Technologies, Inc., Initial Term Loan, 5/17/19 1,377,437 ------------- $ 6,777,422 ----------------------------------------------------------------------------------------------------- Trading Companies & Distributors -- 0.4% 1,450,000 4.25 Univar USA, Inc., Initial Dollar Term Loan, 6/25/22 $ 1,429,285 817,831 3.75 WESCO Distribution, Inc., Tranche B-1 Loan, 12/12/19 818,598 ------------- $ 2,247,883 ------------- Total Capital Goods $ 52,192,176 ----------------------------------------------------------------------------------------------------- COMMERCIAL SERVICES & SUPPLIES -- 3.2% Environmental & Facilities Services -- 1.3% 471,732 3.75 ADS Waste Holdings, Inc., Initial Tranche B-2, 10/9/19 $ 466,622 1,246,875 5.25 Infiltrator Water Technologies, LLC, Term B Loan, 5/21/22 1,247,498 1,169,125 0.00 Waste Industries USA, Inc., Initial Term Loan, 2/20/20 (d) 1,174,483 1,940,421 5.50 Wastequip LLC, Term Loan, 8/9/19 1,933,954 1,956,500 4.00 WCA Waste Corp., Term Loan, 3/23/18 1,947,940 950,670 5.00 Wheelabrator, Term B Loan, 10/15/21 930,469 42,146 5.00 Wheelabrator, Term C Loan, 10/15/21 41,250 ------------- $ 7,742,216 ----------------------------------------------------------------------------------------------------- Diversified Support Services -- 0.8% 2,058,694 4.00 EMI Music, First Lien Term Loan, 8/14/22 $ 2,059,553 251,609 5.37 IAP Worldwide Services, Inc., Term Loan, 7/18/19 252,867 502,553 7.50 infoGroup, Inc., Term B Loan, 5/26/18 478,682 1,465,709 0.00 Language Line, LLC, Initial Term Loan (First Lien), 7/2/21 (d) 1,465,709 790,000 0.00 Ryan, LLC, Tranche B Term Loan, 8/5/20 (d) 782,100 ------------- $ 5,038,911 ----------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 25 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Security & Alarm Services -- 0.7% 912,805 4.25 Allied Security Holdings LLC, Closing Date Term Loan (First Lien), 2/12/21 $ 895,690 505,737 4.00 Garda World Security Corp., Term B Delayed Draw Loan, 11/8/20 493,726 1,976,973 4.00 Garda World Security Corp., Term B Loan, 11/1/20 1,930,020 831,069 4.25 Monitronics International, Inc., Term B Loan, 3/23/18 827,329 ------------- $ 4,146,765 -------------------------------------------------------------------------------------------------- Human Resource & Employment Services -- 0.2% 1,280,493 3.75 On Assignment, Inc., Initial Term B Loan, 6/5/22 $ 1,284,217 -------------------------------------------------------------------------------------------------- Research & Consulting Services -- 0.2% 903,444 5.00 Wyle, Tranche B Loan (First Lien), 5/22/21 $ 901,366 ------------- Total Commercial Services & Supplies $ 19,113,475 -------------------------------------------------------------------------------------------------- TRANSPORTATION -- 3.6% Air Freight & Logistics -- 0.8% 541,872 6.50 CEVA Group Plc, Pre-Funded L/C Loan, 3/19/21 $ 478,653 562,857 6.50 Ceva Intercompany BV, Dutch BV Term, 3/19/21 497,190 97,044 6.50 Ceva Logistics Canada, ULC, Canadian Term Loan, 3/19/21 85,722 776,355 6.50 Ceva Logistics U.S. Holdings, Inc., US Term Loan, 3/19/21 685,780 1,686,188 6.75 Ozburn-Hessey Holding Co LLC, 5/23/19 1,678,810 1,670,250 5.25 Syncreon Group BV, Term Loan, 9/26/20 1,343,160 ------------- $ 4,769,315 -------------------------------------------------------------------------------------------------- Airlines -- 2.0% 1,580,000 4.00 Air Canada, Replacement Term Loan, 9/26/19 $ 1,586,420 3,969,300 0.00 American Airlines, Inc., 2015 Term Loan, 6/27/20 (d) 3,946,973 2,315,534 3.25 Atlantic Aviation FBO, Inc., Term Loan (2013), 6/1/20 2,307,332 600,000 3.25 Delta Air Lines, Inc., Term Loan, 8/24/22 601,050 1,706,250 3.25 United Airlines, Inc., Class B Term Loan, 4/1/19 1,703,051 889,875 3.50 US Airways, Inc., Tranche B-1 Term Loan (Consenting), 5/23/19 887,187 493,226 3.00 US Airways, Inc., Tranche B-2 Term Loan (Consenting), 11/23/16 492,815 ------------- $ 11,524,828 -------------------------------------------------------------------------------------------------- Marine -- 0.5% 926,449 7.50 Commercial Barge Line Co., Initial Term Loan (First Lien), 9/22/19 $ 922,396 The accompanying notes are an integral part of these financial statements. 26 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Marine (continued) 1,953,959 5.25 Navios Maritime Partners LP, Term Loan, 6/27/18 $ 1,941,746 ------------- $ 2,864,142 -------------------------------------------------------------------------------------------------- Trucking -- 0.2% 884,564 5.50 Aegis Toxicology Corp., Tranche B Term Loan (First Lien), 2/20/21 $ 804,953 47,872 1.50 The Kenan Advantage Group, Inc., Delayed Draw Term 1 Loan, 1/24/17 47,783 109,338 4.00 The Kenan Advantage Group, Inc., Initial Canadian Term Loan, 7/24/22 109,133 342,790 4.00 The Kenan Advantage Group, Inc., Initial U.S. Term Loan, 7/24/22 342,147 ------------- $ 1,304,016 -------------------------------------------------------------------------------------------------- Marine Ports & Services -- 0.1% 774,080 5.25 SeaStar Solutions, Term Loan, 1/22/21 $ 774,080 ------------- Total Transportation $ 21,236,381 -------------------------------------------------------------------------------------------------- AUTOMOBILES & COMPONENTS -- 3.8% Auto Parts & Equipment -- 2.4% 1,330,532 4.94 Affinia Group, Inc., Tranche B-2 Term Loan, 4/25/20 $ 1,332,594 2,280,094 3.50 Allison Transmission, Inc., Term B-3 Loan, 8/23/19 2,285,368 1,086,250 4.00 Cooper Standard Intermediate Holdco 2 LLC, Term Loan, 3/28/21 1,078,329 249,370 0.00 Electrical Components International, Inc., First Lien Term Loan, 4/17/21 (d) 249,993 427,492 0.00 Key Safety Systems, Inc., Initial Term Loan, 7/28/21 (d) 423,751 1,457,518 3.75 MPG Holdco I, Inc., Initial Term Loan, 10/20/21 1,452,182 1,900,000 5.25 Remy International, Inc., Term B Loan 2013, 3/5/20 1,902,970 1,090,061 4.25 Schaeffler AG, Facility B-USD, 5/15/20 1,095,342 971,454 4.50 TI Group Automotive Systems LLC, Initial US Term Loan, 6/25/22 965,382 3,335,014 4.00 Tower Automotive Holdings USA LLC, Initial Term Loan (2014), 4/23/20 3,312,780 ------------- $ 14,098,691 -------------------------------------------------------------------------------------------------- Tires & Rubber -- 0.3% 1,812,500 3.75 The Goodyear Tire & Rubber Co., Term Loan (Second Lien), 3/27/19 $ 1,818,889 -------------------------------------------------------------------------------------------------- Automobile Manufacturers -- 1.0% 2,441,699 3.50 Chrysler Group LLC, Term Loan B, 5/24/17 $ 2,440,422 1,970,000 3.25 Chrysler Group LLC, Tranche B Term Loan, 12/29/18 1,965,321 1,212,750 6.00 Crown Group llc, Term Loan (First Lien), 9/30/20 1,207,826 ------------- $ 5,613,569 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 27 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Personal Products -- 0.1% 807,917 3.50 Visteon Corp., Tranche B Loan (First Lien), 4/8/21 $ 806,227 ------------- Total Automobiles & Components $ 22,337,376 -------------------------------------------------------------------------------------------------- CONSUMER DURABLES & APPAREL -- 1.9% Home Furnishings -- 0.5% 2,581,653 4.25 Serta Simmons Bedding LLC, Term Loan, 10/1/19 $ 2,585,608 174,361 3.50 Tempur Sealy International, Inc., New Term B Loan, 3/18/20 174,760 ------------- $ 2,760,368 -------------------------------------------------------------------------------------------------- Housewares & Specialties -- 0.9% 2,490,717 4.50 Reynolds Group Holdings, Inc., Incremental U.S. Term Loan, 12/31/18 $ 2,497,566 2,537,328 5.50 World Kitchen LLC, U.S. Term Loan, 3/4/19 2,550,015 ------------- $ 5,047,581 -------------------------------------------------------------------------------------------------- Leisure Products -- 0.3% 2,028,857 3.75 Bombardier Recreational Products, Inc., Term B-2 Loan, 1/30/19 $ 2,030,125 -------------------------------------------------------------------------------------------------- Apparel, Accessories & Luxury Goods -- 0.2% 1,349,771 3.25 PVH Corp., Tranche B Term Loan, 12/19/19 $ 1,357,543 ------------- Total Consumer Durables & Apparel $ 11,195,617 -------------------------------------------------------------------------------------------------- CONSUMER SERVICES -- 6.6% Casinos & Gaming -- 1.9% 4,091,691 4.25 CityCenter Holdings LLC, Term B Loan, 10/16/20 $ 4,098,086 872,813 0.00 Eldorado Resorts, Inc., Initial Term Loan, 7/17/22 (d) 873,897 2,921,156 3.50 MGM Resorts International, Term B Loan, 12/20/19 2,919,681 258,181 3.75 Pinnacle Entertainment, Inc., Tranche B-2 Term Loan, 8/13/20 258,181 3,002,313 6.00 Scientific Games, Initial Term B-2, 10/1/21 2,939,921 ------------- $ 11,089,766 -------------------------------------------------------------------------------------------------- Hotels, Resorts & Cruise Lines -- 1.1% 2,738,410 3.50 Four Seasons Holdings Inc., Term Loan, 6/27/20 $ 2,719,014 1,134,079 3.50 Hilton Worldwide Finance LLC, Initial Term Loan, 9/23/20 1,137,701 1,666,000 4.00 Sabre GLBL, Inc., Incremental Term Loan, 2/19/19 1,667,749 1,052,472 4.00 Sabre GLBL, Inc., Term B Loan, 2/19/19 1,053,656 ------------- $ 6,578,120 -------------------------------------------------------------------------------------------------- Leisure Facilities -- 0.8% 1,520,311 3.25 Cedar Fair LP, U.S. Term Facility, 3/6/20 $ 1,527,438 997,475 5.50 L.A. Fitness International, LLC, Tranche B Term Loan (First Lien), 4/25/20 949,679 773,063 0.00 Life Time Fitness, Inc., Closing Date Term Loan, 6/4/22 (d) 769,801 The accompanying notes are an integral part of these financial statements. 28 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Leisure Facilities (continued) 1,695,750 3.50 Six Flags Theme Parks, Inc., Tranche B Term Loan, 6/30/22 $ 1,701,580 ------------- $ 4,948,498 -------------------------------------------------------------------------------------------------- Restaurants -- 0.8% 681,360 3.75 1011778 BC ULC, Term B-2 Loan, 12/12/21 $ 682,455 1,709,246 4.00 Landry's, Inc., B Term Loan, 4/24/18 1,713,242 2,381,564 4.25 PF Chang's China Bistro, Inc., Term Borrowing, 7/2/19 2,327,979 ------------- $ 4,723,676 -------------------------------------------------------------------------------------------------- Education Services -- 1.1% 2,612,666 3.75 Bright Horizons Family Solutions, Inc., Term B Loan, 1/14/20 $ 2,619,731 3,425,575 5.00 Laureate Education, Inc., New Series 2018 Extended Term Loan, 6/16/18 2,958,841 1,043,101 0.00 McGraw-Hill Global Education Holdings, LLC, Term B Loan, 3/22/19 (d) 1,046,035 ------------- $ 6,624,607 -------------------------------------------------------------------------------------------------- Specialized Consumer Services -- 0.9% 348,496 0.00 Creative Artists Agency, LLC, Amendment No. 3 Incremental Term Loan, 12/10/21 (d) $ 349,748 623,422 0.00 Genex Holdings, Inc., Term B Loan (First Lien), 5/22/21 (d) 621,474 2,000,000 6.00 KC Mergersub, Inc., Initial Term Loan (First Lien), 8/13/22 1,980,000 1,452,627 0.00 Prime Security Services Borrower, LLC, Term B Loan (First Lien), 6/19/21 (d) 1,446,635 921,144 4.00 Weight Watchers International, Inc., Initial Tranche B-2 Term Loan, 4/2/20 719,260 ------------- $ 5,117,117 ------------- Total Consumer Services $ 39,081,784 -------------------------------------------------------------------------------------------------- MEDIA -- 9.3% Advertising -- 0.9% 2,597,664 6.75 Affinion Group, Inc., Tranche B Term Loan, 4/30/18 $ 2,501,335 2,871,229 0.00 Consolidated Precision Products, First Lien Term Loan, 12/28/19 (d) 2,818,591 ------------- $ 5,319,926 -------------------------------------------------------------------------------------------------- Broadcasting -- 2.0% 1,155,375 4.50 Catalina Holding Corp., Tranche B Term Loan (First Lien), 4/3/21 $ 996,511 699,662 3.00 CBS Outdoor Americas Capital llc, Tranche B Term Loan (First Lien), 1/15/21 697,257 1,786,951 4.00 Entercom Radio llc, Term B-2 Loan, 11/23/18 1,788,067 The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 29 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Broadcasting (continued) 1,910,417 4.25 Hubbard Radio LLC, Term Loan, 5/12/22 $ 1,878,178 1,470,000 3.25 Quebecor Media, Inc., Facility B-1 Tranche, 8/17/20 1,428,198 713,357 3.00 Sinclair Television Group, Inc., New Tranche B Term Loan, 4/19/20 703,994 584,287 0.00 Townsquare Media, Inc., Initial Term Loan, 3/17/22 (d) 585,017 2,830,464 3.81 Tribune Media Company, Term B Loan, 12/27/20 2,828,661 730,969 4.00 Univision Communications, Inc., 2013 Incremental Term Loan, 3/1/20 727,028 ------------- $ 11,632,911 -------------------------------------------------------------------------------------------------- Cable & Satellite -- 3.4% 2,391,635 3.50 Cequel Communications LLC, Term Loan, 2/14/19 $ 2,370,409 4,789,750 3.00 Charter Communications Operating LLC, Term F Loan, 1/1/21 4,747,842 1,800,000 0.00 Charter Communications Operating, LLC, Term F Loan, 1/23/23 (d) 1,800,563 1,913,109 3.75 Intelsat Jackson Holdings SA, Tranche B-2 Term Loan, 6/30/19 1,857,809 442,534 4.50 Learfield Communications, Inc., 2014 Replacement Term Loan (First Lien), 10/9/20 442,949 1,697,500 4.00 MCC Georgia LLC, Tranche G Term Loan, 2/8/20 1,697,500 469,200 3.25 MCC Iowa LLC, Tranche H Term Loan, 1/29/21 464,362 2,452,419 3.50 Telesat Canada, U.S. Term B Loan, 3/28/19 2,440,157 1,218,206 4.50 WideOpenWest Finance LLC, Replacement Term B Loan, 4/1/19 1,202,852 1,207,098 3.50 Ziggo BV, (USD) Tranche B-3 Term Loan, 1/15/22 1,189,274 1,138,945 3.50 Ziggo BV, Tranche B-1 Term Loan (First Lien), 1/15/22 1,122,127 733,957 3.50 Ziggo BV, Tranche B-2 Term Loan (First Lien), 1/15/22 723,120 ------------- $ 20,058,964 -------------------------------------------------------------------------------------------------- Movies & Entertainment -- 2.1% 2,130,695 3.50 AMC Entertainment, Inc., Initial Term Loan, 4/30/20 $ 2,131,362 2,100,000 5.00 CDS U.S. Intermediate Holdings, Inc., Initial Term Loan (First Lien), 6/25/22 2,110,762 242,444 3.75 Cinedigm Digital Funding 1 LLC, Term Loan, 2/28/18 242,141 1,526,414 3.25 Kasima LLC, Term Loan, 5/17/21 1,525,460 1,528,451 3.50 Live Nation Entertainment, Inc., Term B-1 Loan, 8/17/20 1,528,769 83,333 0.00 NVA Holdings, Inc., Amendment No. 2 Term B Loan, 8/14/21 (d) 83,438 166,247 0.00 NVA Holdings, Inc., Term Loan (First Lien), 8/8/21 (d) 166,455 The accompanying notes are an integral part of these financial statements. 30 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Movies & Entertainment (continued) 1,955,000 3.50 Seminole Hard Rock Entertainment, Inc., New Term Loan B, 5/14/20 $ 1,925,675 3,111,500 3.75 WMG Acquisition Corp., Tranche B Refinancing Term Loan, 7/1/20 3,033,712 ------------- $ 12,747,774 -------------------------------------------------------------------------------------------------- Publishing -- 0.9% 739,765 0.00 Cengage Learning Acquisitions, Inc., Term Loan, 3/6/20 (d) $ 736,529 836,211 4.75 Interactive Data Corp., Tranche B Term Loan (First Lien), 4/24/21 837,079 2,652,750 6.25 McGraw-Hill School Education Holdings llc, Term B Loan, 12/18/19 2,655,238 1,025,000 0.00 Quincy Newspapers, Inc., Term Loan B, 10/19/22 (d) 1,021,156 ------------- $ 5,250,002 ------------- Total Media $ 55,009,577 -------------------------------------------------------------------------------------------------- RETAILING -- 2.3% Department Stores -- 0.3% 1,666,074 4.25 Neiman Marcus Group, Ltd. LLC, Other Term Loan, 10/25/20 $ 1,628,209 -------------------------------------------------------------------------------------------------- Apparel Retail -- 0.2% 1,425,000 0.00 Hudson's Bay Company, Initial Term Loan, 8/14/22 (d) $ 1,429,453 -------------------------------------------------------------------------------------------------- Computer & Electronics Retail -- 0.3% 985,000 3.75 Rent-A-Center, Inc., Term Loan (2014), 2/6/21 $ 975,150 932,729 14.75 Targus Group International, Inc., Term Loan, 5/24/16 699,547 ------------- $ 1,674,697 -------------------------------------------------------------------------------------------------- Home Improvement Retail -- 0.5% 3,367,904 4.50 Apex Tool Group LLC, Term Loan, 2/1/20 $ 3,294,932 -------------------------------------------------------------------------------------------------- Specialty Stores -- 0.3% 522,375 4.25 PetSmart, Inc., Tranche B-1 Loan, 3/10/22 $ 522,909 1,000,000 0.00 Staples, Inc., Initial Loan, 4/24/21 (d) 996,500 ------------- $ 1,519,409 -------------------------------------------------------------------------------------------------- Automotive Retail -- 0.7% 559,647 3.00 Avis Budget Car Rental LLC, Tranche B Term Loan, 3/15/19 $ 558,765 1,152,759 5.25 CWGS Group LLC, Term Loan, 2/20/20 1,153,480 1,701,875 3.75 The Hertz Corp., Tranche B1 Term Loan, 3/11/18 1,701,165 487,500 3.00 The Hertz Corp., Tranche B-2 Term Loan, 3/11/18 483,615 ------------- $ 3,897,025 ------------- Total Retailing $ 13,443,725 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 31 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- FOOD & STAPLES RETAILING -- 1.6% Drug Retail -- 0.1% 691,250 4.50 Hearthside Group Holdings LLC, Term Loan (First Lien), 4/24/21 $ 690,144 -------------------------------------------------------------------------------------------------- Food Distributors -- 0.8% 1,546,949 5.75 AdvancePierre Foods, Inc., Term Loan (First Lien), 7/10/17 $ 1,550,237 1,426,262 4.75 Clearwater Seafoods LP, Term Loan B 2013, 6/26/19 1,425,370 1,727,792 4.26 Del Monte Foods Consumer Products, Inc., Term Loan (First Lien), 11/26/20 1,692,157 ------------- $ 4,667,764 -------------------------------------------------------------------------------------------------- Food Retail -- 0.7% 4,321,387 5.38 Albertsons LLC, Term B-2 Loan, 3/21/19 $ 4,322,467 ------------- Total Food & Staples Retailing $ 9,680,375 -------------------------------------------------------------------------------------------------- FOOD, BEVERAGE & TOBACCO -- 2.7% Agricultural Products -- 0.3% 1,970,000 3.25 Darling International, Inc., Term B USD Loan, 12/19/20 $ 1,968,154 -------------------------------------------------------------------------------------------------- Packaged Foods & Meats -- 2.1% 2,246,192 4.50 Boulder Brands USA, Inc., Term Loan, 7/9/20 $ 2,212,499 3,327,999 5.00 CSM Bakery Solutions LLC, Term Loan (First Lien), 7/3/20 3,300,543 1,749,252 3.75 JBS USA LLC, Initial Term Loan, 5/25/18 1,749,899 2,712,880 3.00 Pinnacle Foods Finance LLC, New Term Loan G, 4/29/20 2,714,144 833,000 3.00 Pinnacle Foods Finance LLC, Tranche H Term Loan, 4/29/20 832,774 306,050 3.75 Post Holdings, Inc., Tranche B Loan (First Lien), 5/23/21 307,005 990,000 4.50 Shearer's Foods, LLC, Term Loan (First Lien), 6/19/21 982,575 ------------- $ 12,099,439 -------------------------------------------------------------------------------------------------- Other Diversified Financial Services -- 0.3% 1,764,000 3.75 JBS USA LLC, Incremental Term Loan, 9/18/20 $ 1,762,342 ------------- Total Food, Beverage & Tobacco $ 15,829,935 -------------------------------------------------------------------------------------------------- HOUSEHOLD & PERSONAL PRODUCTS -- 1.8% Household Products -- 0.7% 498,750 0.00 Energizer Holdings, Inc., Term Loan, 5/20/22 (d) $ 498,638 1,383,464 0.00 Spectrum Brands, Inc., Term Loan, 6/16/22 (d) 1,390,922 2,341,676 4.01 SRAM LLC, Term Loan (First Lien), 4/10/20 2,212,884 ------------- $ 4,102,444 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 32 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Personal Products -- 1.1% 985,000 4.25 Atrium Innovations, Inc., Term Loan, 1/29/21 $ 926,311 250,000 7.75 Atrium Innovations, Inc., Tranche B Term Loan (Second Lien), 7/29/21 219,167 1,597,957 4.75 Federal-Mogul Corporation, Tranche C Term, 4/15/21 1,465,127 2,076,786 3.50 NBTY, Inc., Term B-2 Loan, 10/1/17 2,063,027 500,000 0.00 Party City Holdings, Inc., Term Loan, 8/6/22 (d) 499,896 1,640,215 4.00 Revlon Consumer Products Corp., Acquisition Term Loan, 8/19/19 1,641,496 ------------- $ 6,815,024 ------------- Total Household & Personal Products $ 10,917,468 -------------------------------------------------------------------------------------------------- HEALTH CARE EQUIPMENT & SERVICES -- 6.8% Health Care Equipment -- 0.6% 731,250 0.00 Hill-Rom Holdings, Inc., Initial Term B Loan, 7/30/22 (d) $ 733,078 2,018,018 4.50 Kinetic Concepts, Inc., Term DTL-E1 loan, 5/4/18 2,020,540 875,000 0.00 Physio-Control International, Inc., Initial Term Loan (First Lien), 5/19/22 (d) 862,969 ------------- $ 3,616,587 -------------------------------------------------------------------------------------------------- Health Care Supplies -- 0.6% 1,000,000 0.00 Greatbatch, Inc., Term Loan B, 10/14/22 (d) $ 1,004,375 1,851,560 5.00 Immucor, Inc., Term B-2 Loan, 8/19/18 1,816,843 750,000 0.00 Sterigenics-Nordion Holdings, LLC, Initial Term Loan, 4/27/22 (d) 746,250 ------------- $ 3,567,468 -------------------------------------------------------------------------------------------------- Health Care Services -- 3.2% 1,019,084 4.25 Alliance HealthCare Services, Inc., Initial Term Loan, 6/3/19 $ 1,014,944 350,326 0.00 Ardent Legacy Acquisitions, Inc., Term Loan, 7/31/21 (d) 350,764 1,218,203 6.50 BioScrip, Inc., Initial Term B Loan, 7/31/20 1,120,747 730,922 6.50 BioScrip, Inc., Term Loan, 7/31/20 672,448 1,508,762 4.00 BSN Medical GmbH & Co. KG, Facility B1A, 8/28/19 1,497,446 2,804,354 4.00 Envision Healthcare Corp., Initial Term Loan, 5/25/18 2,802,893 2,940,000 2.33 Fresenius US Finance I, Inc., Tranche B Term Loan, 8/7/19 2,941,838 324,188 0.00 Genoa Healthcare Company, LLC, Initial Term Loan (First Lien), 4/21/22 (d) 323,985 950,000 0.00 Global Healthcare Exchange, LLC, Initial Term Loan, 8/13/22 (d) 948,516 The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 33 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Health Care Services (continued) 1,068,252 4.25 National Mentor Holdings, Inc., Tranche B Term Loan, 1/31/21 $ 1,052,229 687,167 0.00 National Surgical Hospitals, Inc., Term Loan (First Lien), 5/15/22 (d) 675,141 955,730 0.00 Pharmaceutical Product Development, Inc., Initial Term Loan, 8/6/22 (d) 944,579 860,332 0.00 Surgery Center Holdings, Inc., Initial Term Loan (First Lien), 7/24/20 (d) 858,898 1,663,864 4.50 Truven Health Analytics, Inc., New Tranche B Term Loan, 6/6/19 1,636,827 2,180,746 4.25 US Renal Care, Inc., Tranche B-2 Term Loan (First Lien), 7/3/19 2,181,428 ------------- $ 19,022,683 -------------------------------------------------------------------------------------------------- Health Care Facilities -- 1.4% 269,663 3.58 CHS, Incremental 2018 Term F Loans, 12/31/18 $ 268,947 541,778 3.08 CHS, Incremental 2019 Term G Loan, 12/31/19 540,169 996,857 4.00 CHS, Incremental 2021 Term H Loan, 1/27/21 995,542 326,981 3.08 HCA, Inc., Tranche B-4 Term Loan, 5/1/18 327,434 2,354,539 4.25 Kindred Healthcare, Inc., Tranche B Loan (First Lien), 4/10/21 2,351,577 1,462,771 5.25 RegionalCare Hospital Partners, Inc., Term Loan (First Lien), 4/21/19 1,449,058 189,615 3.75 Select Medical Corp., Series E Tranche B Term Loan, 6/1/18 189,378 2,444,975 6.75 Steward Health Care System LLC, Term Loan, 4/10/20 2,425,843 ------------- $ 8,547,948 -------------------------------------------------------------------------------------------------- Managed Health Care -- 0.1% 257,755 9.75 MMM Holdings, Inc., Term Loan, 10/9/17 (e) $ 190,739 187,387 9.75 MSO of Puerto Rico, Inc., MSO Term Loan, 12/12/17 (e) 138,666 ------------- $ 329,405 -------------------------------------------------------------------------------------------------- Health Care Technology -- 0.9% 613,463 4.25 ConvaTec, Inc., Dollar Term Loan, 12/22/16 $ 613,207 2,426,892 3.75 Emdeon, Inc., Term B-2 Loan, 11/2/18 2,415,769 972,466 3.50 IMS Health, Inc., Term B Dollar Loan, 3/17/21 969,348 1,257,194 4.00 MedAssets, Inc., Term B Loan, 12/13/19 1,251,286 ------------- $ 5,249,610 ------------- Total Health Care Equipment & Services $ 40,333,701 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 34 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- PHARMACEUTICALS, BIOTECHNOLOGY & LIFE SCIENCES -- 3.7% Biotechnology -- 0.8% 3,189,394 3.50 Alkermes, Inc., 2019 Term Loan, 9/25/19 $ 3,190,724 1,795,500 7.00 Lantheus Medical Imaging, Inc., Initial Term Loan, 6/25/22 1,678,792 ------------- $ 4,869,516 -------------------------------------------------------------------------------------------------- Pharmaceuticals -- 2.4% 1,683,000 5.50 Akorn, Inc., Term Loan B, 11/13/20 $ 1,666,170 1,250,000 0.00 Concordia Healthcare Corp., Initial Dollar Term Loan, 10/20/21 (d) 1,205,469 416,487 0.00 Endo International, First Lien Term Loan, 6/24/22 (d) 410,604 1,182,000 3.19 Grifols Worldwide Operations USA, Inc., U.S. Tranche B Term Loam, 4/1/21 1,181,200 2,093,500 4.25 JLL, Initial Dollar Term Loan, 1/23/21 2,055,294 1,379,000 3.25 Mallinckrodt International Finance SA, Initial Term B Loan, 3/6/21 1,313,306 1,244,355 4.25 PharMEDium Healthcare Corp., Initial Term Loan (First Lien), 1/23/21 1,243,058 852,171 3.50 Prestige Brands, Inc., Term B-3 Loan, 9/3/21 853,680 355,750 3.25 RPI Finance Trust, Term B-3 Term Loan, 11/9/18 355,884 1,086,875 3.50 RPI Finance Trust, Term B-4 Term Loan, 11/9/20 1,084,950 1,279,190 3.75 Valeant Pharmaceuticals International, Inc., Series C-2 Tranche B Term Loan, 12/11/19 1,199,880 1,990,492 3.75 Valeant Pharmaceuticals International, Inc., Series E1 Tranche B Term Loan, 8/5/20 1,855,138 ------------- $ 14,424,633 -------------------------------------------------------------------------------------------------- Life Sciences Tools & Services -- 0.5% 2,250,000 5.75 Albany Molecular Research, Inc., Term Loan B, 7/14/21 $ 2,252,812 413,024 4.25 Catalent Pharma Solutions, Dollar Term Loan, 5/20/21 413,116 ------------- $ 2,665,928 ------------- Total Pharmaceuticals, Biotechnology & Life Sciences $ 21,960,077 -------------------------------------------------------------------------------------------------- BANKS -- 0.2% Thrifts & Mortgage Finance -- 0.2% 953,124 5.50 Ocwen Financial Corp., Initial Term Loan, 1/15/18 $ 955,698 ------------- Total Banks $ 955,698 -------------------------------------------------------------------------------------------------- DIVERSIFIED FINANCIALS -- 3.6% Other Diversified Financial Services -- 1.8% 742,500 5.50 4L Technologies Inc., Term Loan, 5/8/20 $ 705,375 1,133,546 3.50 AWAS Finance Luxembourg 2012 SA, Term Loan, 7/16/18 1,131,421 The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 35 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Other Diversified Financial Services (continued) 1,470,000 4.50 CTI Foods Holding Co LLC, Term Loan (First Lien), 6/29/20 $ 1,440,600 475,000 3.50 Delos Finance SARL, Tranche B Term Loan, 2/27/21 475,544 2,591,240 3.50 Fly Funding II Sarl, Term Loan, 8/9/18 2,582,739 2,492,625 5.00 Livingston International, Inc., Initial Term B-1 Loan (First Lien), 4/18/19 2,343,068 1,962,103 5.00 Nord Anglia Education, Initial Term Loan, 3/31/21 1,917,956 ------------- $ 10,596,703 -------------------------------------------------------------------------------------------------- Specialized Finance -- 0.5% 1,622,274 4.25 Mirror BidCo Corp., New Incremental Term Loan, 12/18/19 $ 1,618,218 124,688 0.00 Royal Holdings, Inc., Initial Term Loan (First Lien), 6/12/22 (d) 123,939 175,000 0.00 Royal Holdings, Inc., Initial Term Loan (Second Lien), 6/12/23 (d) 174,781 1,285,425 0.00 Trans Union, LLC, 2015 Term B-2 Loan, 4/9/21 (d) 1,271,607 ------------- $ 3,188,545 -------------------------------------------------------------------------------------------------- Asset Management & Custody Banks -- 0.5% 1,051,948 0.00 Clondalkin Acquisition B. V., Term Loan, 5/31/20 (d) $ 1,046,688 1,887,360 0.00 Vistra Group Limited, Term Loan First Lien, 7/21/22 (d) 1,892,078 ------------- $ 2,938,766 -------------------------------------------------------------------------------------------------- Investment Banking & Brokerage -- 0.8% 498,750 4.00 Concentra, Inc., Tranche B Term Loan (First Lien), 5/8/22 $ 499,161 1,980,550 4.75 Duff & Phelps Corp., Initial Term Loan, 4/23/20 1,970,648 1,947,595 4.25 Guggenheim Partners Investment Management Holdings LLC, Initial Term Loan, 7/22/20 1,950,029 ------------- $ 4,419,838 ------------- Total Diversified Financials $ 21,143,852 -------------------------------------------------------------------------------------------------- INSURANCE -- 1.2% Insurance Brokers -- 0.6% 1,140,743 5.00 CGSC of Delaware Holdings Corp., Term Loan (First Lien), 4/16/20 $ 1,036,174 299,245 4.50 National Financial Partners Corp., Tranche B Term Loan (First Lien), 7/1/20 295,738 2,068,352 4.25 USI Insurance Services LLC, Term B Loan, 12/30/19 2,050,254 ------------- $ 3,382,166 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 36 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Life & Health Insurance -- 0.2% 902,778 6.75 Integro Ltd., Term Loan, 10/9/22 $ 875,694 -------------------------------------------------------------------------------------------------- Multi-line Insurance -- 0.1% 682,890 4.50 Alliant Holdings I LLC, Initial Term Loan, 7/28/22 $ 676,702 -------------------------------------------------------------------------------------------------- Property & Casualty Insurance -- 0.3% 2,123,877 5.75 Confie Seguros Holding II Co., Term B Loan (First Lien), 11/9/18 $ 2,129,187 ------------- Total Insurance $ 7,063,749 -------------------------------------------------------------------------------------------------- REAL ESTATE -- 1.6% Mortgage REIT -- 0.3% 2,097,841 3.50 Starwood Property Trust, Inc., Term Loan (First Lien), 4/17/20 $ 2,082,107 -------------------------------------------------------------------------------------------------- Retail REIT -- 0.2% 997,500 4.25 DTZ US Borrower LLC, 2015-1 Additional Term Loan (First Lien), 11/4/21 $ 989,863 -------------------------------------------------------------------------------------------------- Specialized REIT -- 0.5% 997,500 0.00 Communications Sales & Leasing, Inc., Term Loan First Lien, 10/16/22 (d) $ 943,468 2,301,000 3.25 The GEO Group, Inc., Term Loan, 4/3/20 2,303,876 ------------- $ 3,247,344 -------------------------------------------------------------------------------------------------- Real Estate Services -- 0.6% 2,140,842 4.50 Altisource Solutions Sarl, Term B Loan, 12/9/20 $ 1,921,406 1,494,201 4.25 GCA Services Group, Inc., Replacement Term Loan (First Lien), 11/1/19 1,491,399 ------------- $ 3,412,805 ------------- Total Real Estate $ 9,732,119 -------------------------------------------------------------------------------------------------- SOFTWARE & SERVICES -- 4.8% Internet Software & Services -- 0.2% 988,581 6.00 Vocus, Inc., Tranche B Loan (First Lien), 5/23/21 $ 972,929 -------------------------------------------------------------------------------------------------- IT Consulting & Other Services -- 0.9% 1,402,167 3.75 Booz Allen Hamilton, Inc., Refinance Tranche B, 7/31/19 $ 1,407,074 1,975,000 5.75 Evergreen Skills Lux Sarl, Initial Term Loan (First Lien), 4/23/21 1,651,594 684,575 4.50 PSAV Presentation Services, Tranche B Term Loan (First Lien), 1/24/21 674,306 870,625 3.75 Science Applications International Corporation, Tranche B Incremental Loan, 4/21/22 872,620 681,538 0.00 SunGard Data Systems, Inc.,Tranche E Term Loan, 3/11/20 (d) 681,879 ------------- $ 5,287,473 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 37 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Data Processing & Outsourced Services -- 0.3% 249,375 3.75 Black Knight InfoServ, LLC, Term B Loan, 5/7/22 $ 250,310 1,637,680 3.70 First Data Corp., 2018 New Dollar Term Loan, 3/24/18 1,628,298 ------------- $ 1,878,608 -------------------------------------------------------------------------------------------------- Application Software -- 2.0% 1,596,367 4.25 Applied Systems, Inc., Initial Term Loan (First Lien), 1/15/21 $ 1,588,528 2,445,799 4.50 Epiq Systems, Inc., Term Loan, 8/27/20 2,433,570 652,397 8.50 Expert Global Solutions, Inc., Term B Advance (First Lien), 4/3/18 647,912 1,112,213 3.75 Infor., Tranche B-5 Term Loan (First Lien), 6/3/20 1,084,562 1,244,378 7.50 Serena Software, Inc., Term Loan, 4/10/20 1,241,657 1,243,115 6.25 STG-Fairway Acquisitions, Inc., Term Loan (First Lien), 3/4/19 1,233,015 1,728,237 3.50 Verint Systems, Inc., Tranche B-2 Term Loan (First Lien), 9/6/19 1,728,237 2,188,681 4.25 Vertafore, Inc., Term Loan (2013), 10/3/19 2,191,189 ------------- $ 12,148,670 -------------------------------------------------------------------------------------------------- Systems Software -- 0.9% 547,592 0.00 Avast Software, First Lien Term Loan, 3/20/20 (d) $ 546,908 1,240,625 5.75 AVG Technologies N.V., Term Loan, 10/15/20 1,241,400 2,800,088 4.00 EZE Software Group LLC, Term B-1 Loan, 4/6/20 2,783,755 493,750 5.00 MSC Software Corp., Initial Term Loan (First Lien), 5/28/20 487,270 ------------- $ 5,059,333 -------------------------------------------------------------------------------------------------- Home Entertainment Software -- 0.5% 1,644,500 3.25 Activision Blizzard, Inc., Term Loan, 7/26/20 $ 1,651,298 1,162,493 5.25 Micro Focus International, Term Loan B, 10/7/21 1,162,908 ------------- $ 2,814,206 ------------- Total Software & Services $ 28,161,219 -------------------------------------------------------------------------------------------------- TECHNOLOGY HARDWARE & EQUIPMENT -- 1.5% Communications Equipment -- 0.2% 395,000 3.75 Ciena Corp., Term Loan, 7/15/19 $ 394,012 350,000 0.00 Commscope, Inc., First Lien Term Loan, 5/29/22 (d) 350,438 721,927 3.25 Commscope, Inc., Tranche 4 Term Loan, 1/14/18 719,103 ------------- $ 1,463,553 -------------------------------------------------------------------------------------------------- Electronic Equipment Manufacturers -- 0.4% 956,952 4.50 Sensus USA, Inc., Term Loan (First Lien), 5/9/17 $ 954,560 1,505,455 4.75 Zebra Technologies, Term Loan B, 9/30/21 1,517,677 ------------- $ 2,472,237 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 38 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Electronic Components -- 0.2% 147,000 3.25 Belden Finance 2013 LP, Initial Term Loan, 9/9/20 $ 146,860 484,763 6.25 FCI -- Fidji Luxembourg Bc4 Sarl , Term Loan, 12/19/20 484,762 337,154 3.50 Generac Power Systems, Inc., Term Loan B, 5/31/20 333,782 ------------- $ 965,404 -------------------------------------------------------------------------------------------------- Technology Distributors -- 0.7% 780,006 3.25 CDW LLC, Term Loan, 4/25/20 $ 778,868 1,390,315 0.00 Deltek, Inc., Term Loan (First Lien), 12/31/22 (d) 1,390,894 229,439 0.00 SS&C European Holdings, Term B-2 Loan, 6/29/22 (d) 230,421 1,482,859 0.00 SS&C Technologies, Inc., Term B-1 Loan, 6/29/22 (d) 1,489,204 ------------- $ 3,889,387 ------------- Total Technology Hardware & Equipment $ 8,790,581 -------------------------------------------------------------------------------------------------- SEMICONDUCTORS & SEMICONDUCTOR EQUIPMENT -- 1.2% Semiconductor Equipment -- 0.4% 1,101,117 3.50 Emtegris, Inc., Term Loan B, 3/25/21 $ 1,098,365 477,951 2.58 Sensata Technologies Finance Company, LLC, Term Loan First Lien, 10/14/21 478,547 1,206,851 0.00 Vat, First Lien Term Loan, 2/11/21 (d) 1,205,846 ------------- $ 2,782,758 -------------------------------------------------------------------------------------------------- Semiconductors -- 0.8% 3,434,067 3.75 Avago Technologies Ltd., Tranche B Term Loan (First Lien), 4/16/21 $ 3,437,168 493,750 4.50 M/A-COM Technology, Initial Term Loan, 5/7/21 495,602 653,666 3.25 Microsemi Corp., Term Loan (First Lien), 3/14/21 651,725 ------------- $ 4,584,495 ------------- Total Semiconductors & Semiconductor Equipment $ 7,367,253 -------------------------------------------------------------------------------------------------- TELECOMMUNICATION SERVICES -- 2.5% Integrated Telecommunication Services -- 1.1% 2,744,000 4.00 Cincinnati Bell, Inc., Tranche B Term Loan, 9/10/20 $ 2,715,874 263,675 3.44 GCI Holdings, Inc., New Term B Loan, 2/2/22 264,993 1,005,731 4.75 Securus Technologies Holdings, Inc., Initial Term Loan (First Lien), 4/30/20 784,470 504,991 3.50 Virgin Media, First Lien Term Loan, 6/30/23 502,072 1,636,644 3.25 West Corp., B-10 Term Loan (First Lien), 6/30/18 1,624,625 980,228 3.50 Windstream Services LLC, Tranche B-5 Term Loan, 8/8/19 960,215 ------------- $ 6,852,249 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 39 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- Wireless Telecommunication Services -- 1.4% 3,079,885 3.00 Crown Castle International Corp., Tranche B-2 Term Loan (First Lien), 1/31/21 $ 3,082,657 1,092,132 4.50 Numericable U.S. LLC, Tranche B-1 Term Loan, 4/23/20 1,079,930 944,546 4.50 Numericable-SFR, Tranche B-2 Loan (First Lien), 4/23/20 933,993 1,175,787 3.32 Syniverse Holdings, Inc., Initial Term Loan, 4/23/19 1,076,580 2,204,282 4.00 Syniverse Holdings, Inc., Tranche B Term Loan, 4/23/19 2,018,296 ------------- $ 8,191,456 ------------- Total Telecommunication Services $ 15,043,705 -------------------------------------------------------------------------------------------------- UTILITIES -- 2.8% Electric Utilities -- 1.1% 1,616,510 4.75 Atlantic Power LP, Term Loan, 2/20/21 $ 1,617,521 2,590,375 3.00 Calpine Construction Finance Co. LP, Term B-1 Loan, 5/3/20 2,528,854 1,894,542 4.25 Star West Generation LLC, Term B Advance, 3/13/20 1,866,124 679,080 3.75 Texas Competitive Electric Holdings Co LLC, DIP Delayed Draw Term Loan (2014), 5/5/16 679,823 ------------- $ 6,692,322 -------------------------------------------------------------------------------------------------- Water Utilities -- 0.3% 1,719,375 4.75 WTG Holdings III Corp., Term Loan (First Lien), 12/12/20 $ 1,711,853 -------------------------------------------------------------------------------------------------- Independent Power Producers & Energy Traders -- 1.4% 534,169 4.00 Calpine Corp., Term Loan, 9/27/19 $ 535,504 1,391,513 0.00 Calpine Corp., First Lien Term Loan, 5/28/22 (d) 1,378,178 1,203,077 4.00 Dynegy, Inc., Tranche B-2 Term Loan, 4/23/20 1,199,640 2,038,396 2.75 NRG Energy, Inc., Term Loan (2013), 7/1/18 1,986,003 3,306,212 3.75 NSG Holdings LLC, New Term Loan, 12/11/19 3,264,841 ------------- $ 8,364,166 ------------- Total Utilities $ 16,768,341 -------------------------------------------------------------------------------------------------- TOTAL SENIOR FLOATING RATE LOAN INTERESTS (Cost $536,933,721) $ 524,718,741 -------------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------- Shares -------------------------------------------------------------------------------------------------- MUTUAL FUNDS -- 0.2% DIVERSIFIED FINANCIALS -- 0.2% Other Diversified Financial Services -- 0.2% 50,000 PowerShares Senior Loan Portfolio $ 1,150,000 ------------- Total Diversified Financials $ 1,150,000 -------------------------------------------------------------------------------------------------- TOTAL MUTUAL FUNDS (Cost $1,192,485) $ 1,150,000 -------------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 40 Pioneer Floating Rate Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------------- TEMPORARY CASH INVESTMENTS -- 1.0% Commercial Paper -- 1.0% 1,475,000 Barclays, Floating Rate Note, 11/2/15 (c) $ 1,474,970 1,475,000 Mondelez, Floating Rate Note, 11/2/15 (c) 1,474,969 1,475,000 Prudential Funding LLC, Floating Rate Note, 11/2/15 (c) 1,474,985 1,475,000 Societe Generale SA, Commercial Paper, 11/2/15 (c) 1,474,990 ------------- $ 5,899,914 -------------------------------------------------------------------------------------------------- TOTAL TEMPORARY CASH INVESTMENTS (Cost $5,899,980) $ 5,899,914 -------------------------------------------------------------------------------------------------- TOTAL INVESTMENT IN SECURITIES -- 95.1% (Cost $576,723,435) (a) $ 563,423,924 -------------------------------------------------------------------------------------------------- OTHER ASSETS & LIABILITIES -- 4.9% $ 28,983,661 -------------------------------------------------------------------------------------------------- TOTAL NET ASSETS -- 100.0% $ 592,407,585 ================================================================================================== + Amount rounds to less than 0.1%. (Cat Bond) Catastrophe or Event-Linked Bond. At October 31, 2015, the value of these securities amounted to $7,301,325, or 1.2% of total net assets. See Notes to Financial Statements -- Note 1H. (144A) Security is exempt from registration under Rule 144A of the Securities Act of 1933. Such securities may be resold normally to qualified institutional buyers in a transaction exempt from registration. At October 31, 2015, the value of these securities amounted to $12,150,125 , or 2.1% of total net assets. REIT Real Estate Investment Trust. (Perpetual) Security with no stated maturity date. ** Senior floating rate loan interests in which the Fund invests generally pay interest at rates that are periodically redetermined by reference to a base lending rate plus a premium. These base lending rates are generally (i) the lending rate offered by one or more major European banks, such as LIBOR (London InterBank Offered Rate), (ii) the prime rate offered by one or more major United States banks, (iii) the rate of a certificate of deposit or (iv) other base lending rates used by commercial lenders. The rate shown is the coupon rate at period end. (a) At October 31, 2015, the net unrealized appreciation (depreciation) on investments based on cost for federal income tax purposes of $576,904,729 was as follows: Aggregate gross unrealized appreciation for all investments in which there is an excess of value over tax cost $ 1,184,725 Aggregate gross unrealized depreciation for all investments in which there is an excess of tax cost over value (14,665,530) ------------ Net unrealized depreciation $(13,480,805) ============ (b) Debt obligation with a variable interest rate. Rate shown is rate at end of period. (c) Security issued with a zero coupon. Income is recognized through accretion of discount. The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 41 Schedule of Investments | 10/31/15 (continued) (d) Rate to be determined. (e) Security is in default. (f) Structured reinsurance investment. At October 31, 2015, the value of these securities amounted to $596,223 or 0.1% of total net assets. See Notes to Financial Statements -- Note 1H. (g) Income is recognized through accretion of discount. Purchases and sales of securities (excluding temporary cash investments) for the year ended October 31, 2015 were as follows: -------------------------------------------------------------------------------- Purchases Sales -------------------------------------------------------------------------------- Long-Term U.S. Government $ 8,896,659 $ -- Other Long-Term Securities $135,277,182 $278,433,024 CENTRALLY CLEARED CREDIT DEFAULT SWAP AGREEMENTS -- SELL PROTECTION ------------------------------------------------------------------------------------------------------------------- Notional Credit Expiration Premiums Unrealized Principal ($)(1) Counterparty Obligation Entity/Index Coupon Rating(2) Date Received Appreciation ------------------------------------------------------------------------------------------------------------------- J.P. Morgan Markit CDX North Chase America High 1,361,250 Bank Yield Index 5.00% B+ 6/20/20 $81,943 $3,954 (1) The notional amount is the maximum amount that a seller of credit protection would be obligated to pay upon occurrence of a credit event. (2) Based on Standard & Poor's rating of the issuer or the weighted average of all the underlying securities in the index. Various inputs are used in determining the value of the Fund's investments. These inputs are summarized in the three broad levels listed below. Level 1 - quoted prices in active markets for identical securities. Level 2 - other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk, etc.) See Notes to Financial Statements -- Note 1A. Level 3 - significant unobservable inputs (including the Fund's own assumptions in determining fair value of investments) See Notes to Financial Statements -- Note 1A. The following is a summary of the inputs used as of October 31, 2015, in valuing the Fund's assets: ----------------------------------------------------------------------------------- Level 1 Level 2 Level 3 Total ----------------------------------------------------------------------------------- Preferred Stocks $1,543,420 $ -- $ -- $ 1,543,420 Convertible Preferred Stock 145,250 -- -- 145,250 Common Stocks 6,253 681,539 -- 687,792 Asset Backed Securities -- 759,548 -- 759,548 Collateralized Mortgage Obligations -- 358,643 -- 358,643 Corporate Bonds Insurance Reinsurance -- 7,301,325 596,223 7,897,548 All Other Corporate Bonds -- 11,371,236 -- 11,371,236 The accompanying notes are an integral part of these financial statements. 42 Pioneer Floating Rate Fund | Annual Report | 10/31/15 ------------------------------------------------------------------------------------- Level 1 Level 2 Level 3 Total ------------------------------------------------------------------------------------- U.S. Government and Agency Obligations -- 8,891,832 -- 8,891,832 Senior Floating Rate Loan Interests -- 524,718,741 -- 524,718,741 Mutual Funds 1,150,000 -- -- 1,150,000 Commercial Paper -- 5,899,914 -- 5,899,914 ------------------------------------------------------------------------------------- Total $ 2,844,923 $559,982,778 $596,223 $563,423,924 ===================================================================================== Other Financial Instruments Unrealized appreciation on credit default swap contracts $ -- $ 3,954 $ -- $ 3,954 ------------------------------------------------------------------------------------- Total Other Financial Instruments $ -- $ 3,954 $ -- $ 3,954 ===================================================================================== The following is a summary of the fair valuation of certain Fund's assets and liabilities as of October 31, 2015: -------------------------------------------------------------------------------- Level 1 Level 2 Level 3 Total -------------------------------------------------------------------------------- Assets: Centrally cleared swap collateral $ -- $ 95,000 $ -- $ 95,000 Variation margin for centrally cleared swap contracts -- 1,439 -- 1,439 -------------------------------------------------------------------------------- Total $ -- $ 96,439 $ -- $ 96,439 ================================================================================ The following is a reconciliation of assets valued using significant unobservable inputs (Level 3): -------------------------------------------------------------------------------- Corporate Bonds -------------------------------------------------------------------------------- Balance as of 10/31/14 $ -- Realized gain (loss)(1) -- Change in unrealized appreciation (depreciation)(2) 48,123 Purchases 548,100 Sales -- Transfers in to Level 3* -- Transfers out of Level 3* -- -------------------------------------------------------------------------------- Balance as of 10/31/15 $ 596,223 ================================================================================ (1) Realized gain (loss) on these securities is included in the net realized gain (loss) from investments in the Statement of Operations. (2) Unrealized appreciation (depreciation) on these securities is included in the change in unrealized appreciation (depreciation) on investments in the Statement of Operations. * Transfers are calculated on the beginning of period values. During the year ended October 31, 2015, there were no transfers between Levels 1, 2 and 3. Net change in unrealized appreciation (depreciation) of investments still held as of 10/31/15 $48,123 ------- The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 43 Statement of Assets and Liabilities | 10/31/15 ASSETS: Investment in securities (cost $576,723,435) $ 563,423,924 Cash 36,291,881 Centrally cleared swap collateral 95,000 Receivables -- Investment securities sold 3,675,158 Fund shares sold 3,629,062 Interest 2,119,383 Dividends 1,260 Centrally cleared swap contracts, premium paid 81,943 Variation margin for centrally cleared swap contracts 1,439 Unrealized appreciation on swap contracts 3,954 Prepaid expenses 37,737 --------------------------------------------------------------------------------- Total assets $ 609,360,741 ================================================================================= LIABILITIES: Payables -- Investment securities purchased $ 14,625,354 Fund shares repurchased 1,687,996 Distributions 195,447 Trustee fees 2,036 Due to affiliates 218,033 Due to Pioneer Investment Management, Inc. 11,145 Accrued expenses 213,145 --------------------------------------------------------------------------------- Total liabilities $ 16,953,156 ================================================================================= NET ASSETS: Paid-in capital $ 614,755,789 Undistributed net investment income 292,477 Accumulated net realized loss on investments and swap contracts (9,348,536) Net unrealized depreciation on investments (13,299,511) Net unrealized appreciation on swap contracts 3,954 Net unrealized appreciation on delayed draw loan commitments 3,412 --------------------------------------------------------------------------------- Total net assets $ 592,407,585 ================================================================================= NET ASSET VALUE PER SHARE: (No par value, unlimited number of shares authorized) Class A (based on $174,978,762/25,992,164 shares) $ 6.73 Class C (based on $92,923,899/13,786,747 shares) $ 6.74 Class K (based on $692,565/102,850 shares) $ 6.73 Class Y (based on $323,812,359/47,956,162 shares) $ 6.75 MAXIMUM OFFERING PRICE: Class A ($6.73 (divided by) 95.5%) $ 7.05 ================================================================================= The accompanying notes are an integral part of these financial statements. 44 Pioneer Floating Rate Fund | Annual Report | 10/31/15 Statement of Operations For the Year Ended 10/31/15 INVESTMENT INCOME: Interest $ 27,931,211 Dividends 318,614 ------------------------------------------------------------------------------------------------- Total investment income $ 28,249,825 ------------------------------------------------------------------------------------------------- EXPENSES: Management fees $ 3,664,292 Transfer agent fees Class A 38,969 Class C 19,787 Class Y 3,648 Class Z* 352 Distribution fees Class A 490,093 Class C 1,005,865 Shareholder communications expense 636,440 Administrative expense 195,332 Custodian fees 63,908 Registration fees 115,156 Professional fees 106,720 Printing expense 49,683 Fees and expenses of nonaffiliated Trustees 24,627 Interest expense 4,553 Miscellaneous 268,364 ------------------------------------------------------------------------------------------------- Total expenses $ 6,687,789 Less fees waived and expenses reimbursed by Pioneer Investment Management, Inc. (471,987) ------------------------------------------------------------------------------------------------- Net expenses $ 6,215,802 ------------------------------------------------------------------------------------------------- Net investment income $ 22,034,023 ------------------------------------------------------------------------------------------------- REALIZED AND UNREALIZED GAIN (LOSS) ON INVESTMENTS, SWAP CONTRACTS AND DELAYED DRAW LOAN COMMITMENTS Net realized gain (loss) on: Investments $ (4,792,836) Swap contracts 4,087 $ (4,788,749) ------------------------------------------------------------------------------------------------- Change in net unrealized appreciation (depreciation) on: Investments $ (7,431,193) Swap contracts 3,954 Delayed draw loan commitments 5,103 $ (7,422,136) ------------------------------------------------------------------------------------------------- Net realized and unrealized loss on investments, swap contracts and delayed draw loan commitments $(12,210,885) ------------------------------------------------------------------------------------------------- Net increase in net assets resulting from operations $ 9,823,138 ================================================================================================= * Class Z shares converted to Class Y shares on August 7, 2015. The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 45 Statements of Changes in Net Assets ------------------------------------------------------------------------------------------- Year Ended Year Ended 10/31/15 10/31/14 ------------------------------------------------------------------------------------------- FROM OPERATIONS: Net investment income $ 22,034,023 $ 30,211,193 Net realized loss on investments and swap contracts (4,788,749) (2,161,487) Change in net unrealized appreciation (depreciation) on investments, swap contracts and delayed draw loan commitments (7,422,136) (8,434,792) ------------------------------------------------------------------------------------------- Net increase in net assets resulting from operations $ 9,823,138 $ 19,614,914 ------------------------------------------------------------------------------------------- DISTRIBUTIONS TO SHAREOWNERS: Net investment income: Class A ($0.23 and $0.24 per share, respectively) $ (6,819,255) $ (9,406,216) Class C ($0.19 and $0.19 per share, respectively) (2,752,797) (3,458,024) Class K* ($0.26 and $0.24 per share, respectively) (19,162) (349) Class Y ($0.26 and $0.26 per share, respectively) (12,261,475) (16,096,732) Class Z** ($0.19 and $0.25 per share, respectively) (102,418) (714,579) ------------------------------------------------------------------------------------------- Total distributions to shareowners $ (21,955,107) $ (29,675,900) ------------------------------------------------------------------------------------------- FROM FUND SHARE TRANSACTIONS: Net proceeds from sale of shares $ 196,814,951 $ 373,641,102 Reinvestment of distributions 19,923,924 28,835,511 Cost of shares repurchased (331,831,538) (512,014,334) ------------------------------------------------------------------------------------------- Net decrease in net assets resulting from Fund share transactions $ (115,092,663) $ (109,537,721) ------------------------------------------------------------------------------------------- Net decrease in net assets $ (127,224,632) $ (119,598,707) NET ASSETS: Beginning of year 719,632,217 839,230,924 ------------------------------------------------------------------------------------------- End of year $ 592,407,585 $ 719,632,217 ------------------------------------------------------------------------------------------- Undistributed net investment income $ 292,477 $ 35,586 =========================================================================================== * Class K shares commenced operations on December 10, 2013. ** Class Z shares converted to Class Y shares on August 7, 2015. The accompanying notes are an integral part of these financial statements. 46 Pioneer Floating Rate Fund | Annual Report | 10/31/15 ------------------------------------------------------------------------------------- Year Ended Year Ended Year Ended Year Ended 10/31/15 10/31/15 10/31/14 10/31/14 Shares Amount Shares Amount ------------------------------------------------------------------------------------- Class A Shares sold 8,071,604 $ 55,022,985 18,836,617 $ 130,797,329 Reinvestment of distributions 957,018 6,514,616 1,388,741 9,629,680 Less shares repurchased (17,843,127) (121,562,711) (23,818,544) (165,075,594) ------------------------------------------------------------------------------------- Net decrease (8,814,505) $ (60,025,110) (3,593,186) $ (24,648,585) ===================================================================================== Class C Shares sold 2,422,862 $ 16,560,977 4,093,630 $ 28,456,600 Reinvestment of distributions 364,313 2,483,342 480,489 3,335,867 Less shares repurchased (5,321,906) (36,300,891) (6,810,541) (47,261,964) ------------------------------------------------------------------------------------- Net decrease (2,534,731) $ (17,256,572) (2,236,422) $ (15,469,497) ===================================================================================== Class K* Shares sold 107,395 $ 730,438 1,439 $ 10,000 Reinvestment of distributions -- -- -- -- Less shares repurchased (5,984) (40,870) -- -- ------------------------------------------------------------------------------------- Net increase 101,411 $ 689,568 1,439 $ 10,000 ===================================================================================== Class Y Shares sold 18,061,494 $ 123,616,077 29,736,107 $ 207,017,300 Reinvestment of distributions 1,585,617 10,825,526 2,173,235 15,108,008 Less shares repurchased (22,868,910) (156,327,282) (41,776,103) (290,364,598) ------------------------------------------------------------------------------------- Net decrease (3,221,799) $ (21,885,679) (9,866,761) $ (68,239,290) ===================================================================================== Class Z** Shares sold 129,737 $ 884,474 1,056,437 $ 7,359,873 Reinvestment of distributions 14,657 100,440 109,575 761,956 Less shares repurchased (2,561,729) (17,599,784) (1,340,586) (9,312,178) ------------------------------------------------------------------------------------- Net decrease (2,417,335) $ (16,614,870) (174,574) $ (1,190,349) ===================================================================================== * Class K shares commenced operations on December 10, 2013. ** Class Z shares converted to Class Y shares on August 7, 2015. The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 47 Financial Highlights --------------------------------------------------------------------------------------------------------------------------- Year Year Year Year Year Ended Ended Ended Ended Ended 10/31/15 10/31/14 10/31/13 10/31/12 10/31/11 --------------------------------------------------------------------------------------------------------------------------- Class A Net asset value, beginning of period $ 6.86 $ 6.95 $ 6.95 $ 6.77 $ 6.87 --------------------------------------------------------------------------------------------------------------------------- Increase (decrease) from investment operations: Net investment income (loss) $ 0.24(a) $ 0.24 $ 0.28 $ 0.33 $ 0.31 Net realized and unrealized gain (loss) on investments (0.14) (0.09) 0.01 0.16 (0.11) --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ 0.10 $ 0.15 $ 0.29 $ 0.49 $ 0.20 --------------------------------------------------------------------------------------------------------------------------- Distribution to shareowners: Net investment income $ (0.23) $ (0.24) $ (0.29) $ (0.31) $ (0.30) --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ (0.13) $ (0.09) $ -- $ 0.18 $ (0.10) --------------------------------------------------------------------------------------------------------------------------- Net asset value, end of period $ 6.73 $ 6.86 $ 6.95 $ 6.95 $ 6.77 =========================================================================================================================== Total return* 1.53% 2.17% 4.24% 7.43% 2.98% Ratio of net expenses to average net assets 1.08% 1.07% 1.06% 1.11% 1.10% Ratio of net investment income (loss) to average net assets 3.48% 3.49% 3.88% 4.77% 4.47% Portfolio turnover rate 24% 43% 40% 42% 57% Net assets, end of period (in thousands) $174,979 $238,764 $ 266,832 $179,260 $176,701 Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly: Total expenses to average net assets 1.10% 1.07% 1.10% 1.11% 1.12% Net investment income (loss) to average net assets 3.46% 3.49% 3.85% 4.77% 4.45% =========================================================================================================================== * 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. (a) The per share data presented above is based on the average shares outstanding for the period presented. The accompanying notes are an integral part of these financial statements. 48 Pioneer Floating Rate Fund | Annual Report | 10/31/15 --------------------------------------------------------------------------------------------------------------------------- Year Year Year Year Year Ended Ended Ended Ended Ended 10/31/15 10/31/14 10/31/13 10/31/12 10/31/11 --------------------------------------------------------------------------------------------------------------------------- Class C Net asset value, beginning of period $ 6.87 $ 6.96 $ 6.95 $ 6.78 $ 6.87 --------------------------------------------------------------------------------------------------------------------------- Increase (decrease) from investment operations: Net investment income (loss) $ 0.19(a) $ 0.19 $ 0.23 $ 0.27 $ 0.26 Net realized and unrealized gain (loss) on investments (0.13) (0.09) 0.02 0.16 (0.10) --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ 0.06 $ 0.10 $ 0.25 $ 0.43 $ 0.16 --------------------------------------------------------------------------------------------------------------------------- Distribution to shareowners: Net investment income $ (0.19) $ (0.19) $ (0.24) $ (0.26) $ (0.25) --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ (0.13) $ (0.09) $ 0.01 $ 0.17 $ (0.09) --------------------------------------------------------------------------------------------------------------------------- Net asset value, end of period $ 6.74 $ 6.87 $ 6.96 $ 6.95 $ 6.78 =========================================================================================================================== Total return* 0.81% 1.43% 3.61% 6.46% 2.33% Ratio of net expenses to average net assets 1.81% 1.78% 1.80% 1.86% 1.89% Ratio of net investment income (loss) to average net assets 2.74% 2.79% 3.13% 4.02% 3.68% Portfolio turnover rate 24% 43% 40% 42% 57% Net assets, end of period (in thousands) $92,924 $112,117 $129,093 $70,655 $65,238 Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly: Total expenses to average net assets 1.84% 1.78% 1.83% 1.86% 1.89% Net investment income (loss) to average net assets 2.71% 2.79% 3.09% 4.02% 3.68% =========================================================================================================================== * 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. (a) The per share data presented above is based on the average shares outstanding for the period presented. The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 49 Financial Highlights (continued) ------------------------------------------------------------------------------------------ Year Ended 12/10/13 to 10/31/15 10/31/14 ------------------------------------------------------------------------------------------ Class K Net asset value, beginning of period $ 6.86 $ 6.95 ------------------------------------------------------------------------------------------ Increase (decrease) from investment operations: Net investment income (loss) $ 0.26(a) $ 0.24 Net realized and unrealized gain (loss) on investments (0.13) (0.09) ------------------------------------------------------------------------------------------ Net increase (decrease) from investment operations $ 0.13 $ 0.15 ------------------------------------------------------------------------------------------ Distribution to shareowners: Net investment income $ (0.26) $ (0.24) ------------------------------------------------------------------------------------------ Net increase (decrease) in net asset value $ (0.13) $ (0.09) ------------------------------------------------------------------------------------------ Net asset value, end of period $ 6.73 $ 6.86 ========================================================================================== Total return* 1.92% 2.21%(b) Ratio of net expenses to average net assets 0.71% 0.69%** Ratio of net investment income (loss) to average net assets 3.81% 3.45%** Portfolio turnover rate 24% 43% Net assets, end of period (in thousands) $ 693 $ 10 Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly: Total expenses to average net assets 0.73% 0.69%** Net investment income (loss) to average net assets 3.79% 3.45%** ========================================================================================== * 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. ** Annualized. (a) The per share data presented above is based on the average shares outstanding for the period presented. (b) Not Annualized. The accompanying notes are an integral part of these financial statements. 50 Pioneer Floating Rate Fund | Annual Report | 10/31/15 --------------------------------------------------------------------------------------------------------------------------- Year Year Year Year Year Ended Ended Ended Ended Ended 10/31/15 10/31/14 10/31/13 10/31/12 10/31/11 --------------------------------------------------------------------------------------------------------------------------- Class Y Net asset value, beginning of period $ 6.88 $ 6.97 $ 6.96 $ 6.78 $ 6.89 --------------------------------------------------------------------------------------------------------------------------- Increase (decrease) from investment operations: Net investment income (loss) $ 0.26(a) $ 0.27 $ 0.31 $ 0.35 $ 0.33 Net realized and unrealized gain (loss) on investments (0.13) (0.10) 0.02 0.16 (0.12) --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ 0.13 $ 0.17 $ 0.33 $ 0.51 $ 0.21 --------------------------------------------------------------------------------------------------------------------------- Distribution to shareowners: Net investment income $ (0.26) $ (0.26) $ (0.32) $ (0.33) $ (0.32) --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ (0.13) $ (0.09) $ 0.01 $ 0.18 $ (0.11) --------------------------------------------------------------------------------------------------------------------------- Net asset value, end of period $ 6.75 $ 6.88 $ 6.97 $ 6.96 $ 6.78 =========================================================================================================================== Total return* 1.92% 2.50% 4.77% 7.78% 3.11% Ratio of net expenses to average net assets 0.70% 0.70% 0.70% 0.70% 0.88% Ratio of net investment income (loss) to average net assets 3.84% 3.86% 4.16% 5.17% 4.70% Portfolio turnover rate 24% 43% 40% 42% 57% Net assets, end of period (in thousands) $323,812 $352,115 $425,245 $18,805 $60,596 Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly: Total expenses to average net assets 0.82% 0.82% 0.83% 0.85% 0.88% Net investment income (loss) to average net assets 3.72% 3.74% 4.04% 5.02% 4.70% =========================================================================================================================== * 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. (a) The per share data presented above is based on the average shares outstanding for the period presented. The accompanying notes are an integral part of these financial statements. Pioneer Floating Rate Fund | Annual Report | 10/31/15 51 Notes to Financial Statements | 10/31/15 1. Organization and Significant Accounting Policies Pioneer Floating Rate Fund (the Fund) is a series of Pioneer Series Trust VI, a Delaware statutory trust. The Fund is registered under the Investment Company Act of 1940 as a diversified, open-end management investment company. The investment objective of the Fund is to produce a high level of current income. The Fund offers four classes of shares designated as Class A, Class C, Class K and Class Y shares. Class K shares commenced operations on December 10, 2013. Class Z shares converted to Class Y shares as of the close of business on August 7, 2015. Each class of shares represents an interest in the same portfolio of investments of the Fund and has identical rights (based on relative net asset values) to assets and liquidation proceeds. Share classes can bear different rates of class-specific fees and expenses such as transfer agent and distribution fees. Differences in class-specific fees and expenses will result in differences in net investment income and, therefore, the payment of different dividends from net investment income earned by each class. The Amended and Restated Declaration of Trust of the Fund gives the Board of Trustees the flexibility to specify either per-share voting or dollar-weighted voting when submitting matters for shareholder approval. Under per-share voting, each share of a class of the Fund is entitled to one vote. Under dollar-weighted voting, a shareholder's voting power is determined not by the number of shares owned, but by the dollar value of the shares on the record date. Each share class has exclusive voting rights with respect to matters affecting only that class, including with respect to the distribution plan for that class. There is no distribution plan for Class K or Class Y shares. The Fund's financial statements have been prepared in conformity with U.S. generally accepted accounting principles that require the management of the Fund to, among other things, make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of income, expenses and gains and losses on investments during the reporting period. Actual results could differ from those estimates. The following is a summary of significant accounting policies followed by the Fund in the preparation of its financial statements: A. Security Valuation Security transactions are recorded as of trade date. The net asset value of the Fund is computed once daily, on each day the New York Stock Exchange (NYSE) is open, as of the close of regular trading on the NYSE. Fixed income 52 Pioneer Floating Rate Fund | Annual Report | 10/31/15 securities are valued at prices supplied by independent pricing services, which consider such factors as market prices, market events, quotations from one or more brokers, Treasury spreads, yields, maturities and ratings. Valuations may be supplemented by dealers and other sources, as required. Senior floating rate loan interests (senior loans) are valued in accordance with guidelines established by the Board of Trustees at the mean between the last available bid and asked prices from one or more brokers or dealers as obtained from Loan Pricing Corporation, an independent pricing service. If price information is not available from Loan Pricing Corporation, or if the price information is deemed to be unreliable, price information will be obtained from an alternative loan interest pricing service. If no reliable price quotes are available from either the primary or 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 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. Shares of money market mutual funds are valued at such funds' net asset value. Cash may include overnight time deposits at approved financial institutions. Trading in foreign securities is substantially completed each day at various times prior to the close of the NYSE. The values of such securities used in computing the net asset value of the Fund's shares are determined as of such times. Securities or senior loans for which independent pricing services are unable to supply prices or for which market prices and/or quotations are not readily available or are considered to be unreliable are valued by a fair valuation team comprised of certain personnel of Pioneer Investment Management, Inc. (PIM), the Fund's investment adviser, pursuant to procedures adopted by the Fund's Board of Trustees. PIM's fair valuation team uses fair value methods approved by the Valuation Committee of the Board of Trustees. PIM's fair valuation team is responsible for monitoring developments that may impact fair valued securities and for discussing and assessing fair values on an ongoing basis, and at least quarterly, with the Valuation Committee of the Board of Trustees. Inputs used when applying fair value methods to value a security may include credit ratings, the financial condition of the company, current market conditions and comparable securities. The Fund may use fair value methods if it is determined that a significant event has occurred after the close of the exchange or market on which the security trades and prior to the determination of the Fund's net asset value. Examples of a significant event might include political or economic news, corporate restructurings, natural Pioneer Floating Rate Fund | Annual Report | 10/31/15 53 disasters, terrorist activity or trading halts. Thus, the valuation of the Fund's securities may differ significantly from exchange prices and such differences could be material. At October 31, 2015 there were no securities that were valued using fair value methods (other than securities valued using prices supplied by independent pricing services or broker-dealers or through a third party using an insurance industry valuation model). B. Investment Income and Transactions Principal amounts of mortgage-backed securities are adjusted for monthly paydowns. Premiums and discounts related to certain mortgage-backed securities are amortized or accreted in proportion to the monthly paydowns. All discounts/premiums on purchase prices of debt securities are accreted/amortized for financial reporting purposes over the life of the respective securities, and such accretion/amortization is included in interest income. Dividend income is recorded on the ex-dividend date, except that certain dividends from foreign securities where the ex-dividend date may have passed are recorded as soon as the Fund becomes aware of the ex-dividend data in the exercise of reasonable diligence. Interest income, including interest on income bearing cash accounts, is recorded on the accrual basis. Dividend and interest income are reported net of unrecoverable foreign taxes withheld at the applicable country rates. Gains and losses on sales of investments are calculated on the identified cost method for both financial reporting and federal income tax purposes. C. Federal Income Taxes It is the Fund's policy to comply with the requirements of the Internal Revenue Code applicable to regulated investment companies and to distribute all of its net taxable income and net realized capital gains, if any, to its shareowners. Therefore, no federal income tax provision is required. As of October 31, 2015, the Fund did not accrue any interest or penalties with respect to uncertain tax positions, which, if applicable, would be recorded as an income tax expense in the Statement of Operations. Tax returns filed within the prior three years remain subject to examination by federal and state tax authorities. The amount and character of income and capital gain distributions to shareowners are determined in accordance with federal income tax rules, which may differ from U.S. generally accepted accounting principles. Distributions in excess of net investment income or net realized gains are temporary overdistributions for financial statement purposes resulting from differences in the recognition or classification of income or distributions for 54 Pioneer Floating Rate Fund | Annual Report | 10/31/15 financial statement and tax purposes. Capital accounts within the financial statements are adjusted for permanent book/tax differences to reflect tax character, but are not adjusted for temporary differences. At October 31, 2015, the Fund reclassified $177,975 to increase undistributed net investment income and $177,975 to increase accumulated net realized loss on investments and swap contracts to reflect permanent book/tax differences. These adjustments have no impact on net assets or the results of operations. At October 31, 2015, the Fund was permitted to carry forward indefinitely $1,458,598 of short-term losses and $5,992,094 of long-term losses under the Regulated Investment Company Modernization Act of 2010 without limitation. Additionally, at October 31, 2015, the Fund had a net capital loss carryforward of $1,891,734 of which the following amounts will expire between 2016 and 2019 if not utilized: $349,923 in 2016, $967,278 in 2017, and $574,533 in 2019. The tax character of distributions paid during the years ended October 31, 2015, and October 31, 2014, were as follows: --------------------------------------------------------------------------- 2015 2014 --------------------------------------------------------------------------- Distributions paid from: Ordinary income $21,955,107 $29,675,900 --------------------------------------------------------------------------- Total $21,955,107 $29,675,900 =========================================================================== The following shows the components of distributable earnings on a federal income tax basis at October 31, 2015: --------------------------------------------------------------------------- 2015 --------------------------------------------------------------------------- Distributable earnings: Undistributed ordinary income $ 661,055 Capital loss carryforward (9,342,426) Dividend payable (195,447) Net unrealized depreciation (13,471,386) --------------------------------------------------------------------------- Total $(22,348,204) =========================================================================== The difference between book basis and tax basis unrealized depreciation is attributable to the tax deferral of losses on wash sales, adjustments relating to catastrophe bonds, the tax treatment of premium and amortization, the mark-to-market of swap contracts, tax basis adjustments on interest accruals on preferred stock, interest on defaulted bonds and other holdings. D. Forward Foreign Currency Contracts The Fund may enter into forward foreign currency contracts (contracts) for the purchase or sale of a specific foreign currency at a fixed price on a future date. All contracts are marked to market daily at the applicable exchange rates, and any resulting unrealized appreciation or depreciation is recorded in Pioneer Floating Rate Fund | Annual Report | 10/31/15 55 the Fund's financial statements. The Fund records realized gains and losses at the time a contract is offset by entry into a closing transaction or extinguished by delivery of the currency. Risks may arise upon entering into these contracts from the potential inability of counterparties to meet the terms of the contract and from unanticipated movements in the value of foreign currencies relative to the U.S. dollar (see Note 6). E. Fund Shares The Fund records sales and repurchases of its shares as of trade date. Pioneer Funds Distributor, Inc. (PFD), the principal underwriter for the Fund and a wholly owned indirect subsidiary of UniCredit S.p.A (UniCredit), earned $19,509 in underwriting commissions on the sale of Class A shares during the year ended October 31, 2015. F. Class Allocations Income, common expenses and realized and unrealized gains and losses are calculated at the Fund level and allocated daily to each class of shares based on its respective percentage of adjusted net assets at the beginning of the day. Distribution fees are calculated based on the average daily net asset value attributable to Class A and Class C shares of the Fund, respectively (see Note 4). Class K and Class Y shares do not pay distribution fees. All expenses and fees paid to the Fund's transfer agent, for its services are allocated among the classes of shares based on the number of accounts in each class and the ratable allocation of related out-of-pocket expenses (see Note 3). The Fund declares as daily dividends substantially all of its net investment income. All dividends are paid on a monthly basis. Short-term capital gain distributions, if any, may be declared with the daily dividends. Distributions to shareowners are recorded as of the ex-dividend date. Distributions paid by the Fund with respect to each class of shares are calculated in the same manner and at the same time, except that net investment income dividends to Class A, Class C, Class K and Class Y shares can reflect different transfer agent and distribution expense rates. G. Risks At times, the Fund's investments may represent industries or industry sectors that are interrelated or have common risks, making the Fund more susceptible to any economic, political, or regulatory developments or other risks affecting those industries and sectors. The Fund invests in below investment grade (high yield) debt securities. Debt securities rated below investment grade are commonly referred to as "junk bonds" and are considered speculative. These 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 rated debt securities. The 56 Pioneer Floating Rate Fund | Annual Report | 10/31/15 Fund's investments in foreign markets or countries with limited developing markets may also subject the Fund to a greater degree of risk than investments in a developed market. Risks associated with these markets include disruptive political or economic conditions and the possible imposition of adverse governmental laws or currency exchange restrictions. The Fund's prospectus contains unaudited information regarding the Fund's principal risks. Please refer to that document when considering the Fund's principal risks. H. Insurance Linked Securities (ILS) The Fund invests in event-linked bonds. Event-linked bonds are floating rate debt obligations for which the return of principal and the payment of interest are contingent on the non-occurrence of a pre-defined "trigger" event, such as a hurricane or an earthquake of a specific magnitude. The trigger event's magnitude may be based on losses to a company or industry, industry indexes or readings of scientific instruments, or may be based on specified actual losses. If a trigger event, as defined within the terms of an event-linked bond occurs, the Fund may lose a portion or all of its accrued interest and/or principal invested in such event-linked bond. The Fund is entitled to receive principal and interest payments so long as no trigger event occurs of the description and magnitude specified by the instrument. In addition to the specified trigger events, event-linked bonds 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 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"), are subject to the same risks as event-linked bonds. In addition, because quota share instruments represent an interest in a basket 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 issuer. Accordingly, it may be more difficult for PIM to fully evaluate the underlying risk profile of the Fund's investment in quota share instruments and therefore place the Fund's assets at greater risk of loss than if PIM had more complete information. Pioneer Floating Rate Fund | Annual Report | 10/31/15 57 Quota share instruments and other structured reinsurance instruments generally will be considered illiquid securities by the Fund. These securities may be difficult to purchase, sell or unwind. Illiquid securities also may be difficult to value. If the Fund is forced to sell an illiquid asset, the Fund may be forced to sell at a loss. I. Repurchase Agreements Repurchase agreements are arrangements under which 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 specific 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. The value of the collateral, including accrued interest, is required to be equal to or in excess of the repurchase price. The collateral for all repurchase agreements is held in safekeeping in the customer-only account of the Fund's custodian or a subcustodian of the Fund. The Fund's investment adviser, PIM is responsible for determining that the value of the collateral remains at least equal to the repurchase price. In the event of a default by the counterparty, 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 to the Fund. 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. As of the year ended October 31, 2015 the fund had no outstanding repurchase agreements. J. Credit Default Swap Agreements A credit default swap is a contract between a buyer of protection and a seller of protection against a pre-defined credit event. The Fund may sell or buy credit default swap contracts to seek to increase the Fund's income, or to attempt to hedge the risk of default on portfolio securities. A credit default swap index is used to hedge risk or take a position on a basket of credit entities or indices. As a seller of protection, the Fund would be required to pay the notional (or other agreed-upon) value of the referenced debt obligation to the counterparty in the event of a default by a U.S. or foreign corporate issuer of a debt obligation, which would likely result in a loss to the Fund. In return, the Fund would receive from the counterparty a periodic stream of payments during the term of the contract provided that no event of default occurred. The maximum exposure of loss to the seller would be the notional value of the credit default swaps outstanding. If no default occurs, the Fund would keep the stream of payments and would have no payment obligation. The Fund may also buy credit default swap contracts in order to hedge against the risk of default of debt securities, in which case the Fund would function as the counterparty referenced above. 58 Pioneer Floating Rate Fund | Annual Report | 10/31/15 When the Fund enters into a credit default swap contract, the protection buyer makes an upfront or periodic payment to the protection seller in exchange for the right to receive a contingent payment. An upfront payment made by the Fund, as the protection buyer, is recorded as an asset in the Statement of Assets and Liabilities. Periodic payments received or paid by the Fund are recorded as realized gains or losses in the Statement of Operations. Credit default swap contracts are marked-to-market daily using valuations supplied by independent sources and the change in value, if any, is recorded as unrealized appreciation or depreciation in the Statement of Assets and Liabilities. Payments received or made as a result of a credit event or upon termination of the contract are recognized, net of the appropriate amount of the upfront payment, as realized gains or losses in the Statement of Operations. Credit default swap contracts involving the sale of protection may involve greater risks than if the Fund had invested in the referenced debt instrument directly. Credit default swap contracts are subject to general market risk, liquidity risk, counterparty risk and credit risk. If the Fund is a protection buyer and no credit event occurs, it will lose its investment. If the Fund is a protection seller and a credit event occurs, the value of the referenced debt instrument received by the Fund, together with the periodic payments received, may be less than the amount the Fund pays to the protection buyer, resulting in a loss to the Fund. Open centrally cleared swap contracts at October 31, 2015, are listed in the Schedule of Investments. The average value of swap contracts open during the year ended October 31, 2015, was $26,898. 2. Management Agreement PIM, a wholly owned indirect subsidiary of UniCredit, manages the Fund's portfolio. Management fees are calculated daily at the annual rate of 0.60% of the Fund's average daily net assets up to $500 million and 0.55% on assets over $500 million. For the year ended October 31, 2015, the annualized management fee (excluding waivers and/or assumption of expenses) was equivalent to 0.59% of the Fund's average daily net assets. PIM has contractually agreed to limit ordinary operating expenses to the extent required to reduce Fund expenses to 0.70% of the Fund's average daily net assets attributable to Class Y shares. Fees waived and expenses reimbursed during the year ended October 31, 2015, are reflected on the Statement of Operations. These expense limitations are in effect through March 1, 2017. There can be no assurance that PIM will extend the expense limitation agreement for a class of shares beyond the date referred to above. Pioneer Floating Rate Fund | Annual Report | 10/31/15 59 In addition, under the management and administration agreements, certain other services and costs, including accounting, regulatory reporting and insurance premiums, are paid by the Fund as administrative reimbursements. Included in "Due to affiliates" reflected on the Statement of Assets and Liabilities is $54,176 in management fees, administrative costs and certain other reimbursements payable to PIM at October 31, 2015. 3. Transfer Agent Pioneer Investment Management Shareholder Services, Inc. (PIMSS), a wholly owned indirect subsidiary of UniCredit, provided substantially all transfer agent and shareowner services to the Fund at negotiated rates. In addition, the Fund reimbursed PIMSS for out-of-pocket expenses incurred by PIMSS related to shareholder communications activities such as proxy and statement mailings, outgoing phone calls and omnibus relationship contracts. For the year ended October 31, 2015, such out-of-pocket expenses by class of shares were as follows: -------------------------------------------------------------------------------- Shareholder Communications: -------------------------------------------------------------------------------- Class A $221,000 Class C 93,400 Class K 5 Class Y 314,179 Class Z 7,856 -------------------------------------------------------------------------------- Total $636,440 ================================================================================ Included in "Due to affiliates" reflected on the Statement of Assets and Liabilities is $152,657 in transfer agent fees and out-of-pocket reimbursements payable to PIMSS at October 31, 2015. 4. Distribution Plan The Fund has adopted a Distribution Plan pursuant to Rule 12b-1 of the Investment Company Act of 1940 with respect to its Class A and Class C shares. Pursuant to the Plan, the Fund pays PFD 0.25% of the average daily net assets attributable to Class A shares as compensation for personal services and/or account maintenance services or distribution services with regard to Class A shares. Pursuant to the Plan, the Fund also pays PFD 1.00% of the average daily net assets attributable to Class C shares. The fee for Class C shares consists of a 0.25% service fee and a 0.75% distribution fee paid as compensation for personal services and/or account maintenance services or distribution services with regard to Class C shares. Included in "Due to affiliates" reflected on the Statement of Assets and Liabilities is $11,200 in distribution fees payable to PFD at October 31, 2015. 60 Pioneer Floating Rate Fund | Annual Report | 10/31/15 In addition, redemptions of each class of shares (except Class Y shares) may be subject to a contingent deferred sales charge (CDSC). A CDSC of 1.00% may be imposed on redemptions of certain net asset value purchases of Class A shares within 12 months of purchase. Redemptions of Class C shares within 12 months of purchase are subject to a CDSC of 1.00%, based on the lower of cost or market value of shares being redeemed. Shares purchases as part of an exchange remain subject to any CDSC that applied to the original purchase of those shares. There is no CDSC for Class Y shares. Proceeds from the CDSCs are paid to PFD. For the year ended October 31, 2015, CDSCs in the amount of $21,647 were paid to PFD. 5. Expense Offset Arrangements The Fund entered into certain expense offset arrangements with PIMSS which may result in a reduction in the Fund's total expenses due to interest earned on cash held by PIMSS. For the year ended October 31, 2015, the Fund's expenses were not reduced under such arrangements. 6. Forward Foreign Currency Contracts At October 31, 2015, the Fund had entered into various forward foreign currency contracts that obligate the Fund to deliver or take delivery of currencies at specified future maturity dates. Alternatively, prior to the settlement date of a forward foreign currency contract, the Fund may close out such contract by entering into an offsetting contract. There were no forward foreign currency contracts outstanding during the year ended October 31, 2015. 7. Line of Credit Facility The Fund, along with certain other funds in the Pioneer Family of Funds (the Funds), participates in a committed, unsecured revolving line of credit facility. Borrowings are used solely for temporary or emergency purposes. The Fund may borrow up to the lesser of the amount available under the facility or the limits set for borrowing by the Fund's prospectus and the 1940 Act. The credit facility in effect until June 9, 2015, was in the amount of $215 million. As of June 9, 2015, the facility is in the amount of $240 million. Under such facility, depending on the type of loan, interest on borrowings is payable at the London Interbank Offered Rate (LIBOR) plus 0.85% on an annualized basis, or the Alternate Base Rate, which is the greater of (a) the facility's administrative agent's daily announced prime rate on the borrowing date, (b) 2% plus the Federal Funds Rate on the borrowing date and (c) 2% plus the overnight Eurodollar rate on the borrowing date. The Funds pay an annual commitment fee to participate in a credit facility. The commitment fee is allocated among participating Funds based on an allocation schedule set forth in the credit agreement. For the year ended October 31, 2015, the average daily amount of borrowings outstanding during the period was $6,266,667. The related weighted average annualized interest rate for the period was 0.96%, and the total interest Pioneer Floating Rate Fund | Annual Report | 10/31/15 61 expense on such borrowings was $4,553, which is included in interest expense, located on the Statement of Operations. As of October 31, 2015, there were no borrowings outstanding. 8. Additional Disclosures about Derivative Instruments and Hedging Activities The Fund's use of derivatives subjects it to the following risks: Interest rate risk relates to the fluctuations in the value of interest-bearing securities due to changes in the prevailing levels of market interest rates. Credit risk relates to the ability of the issuer of a financial instrument to make further principal or interest payments on an obligation or commitment that it has to the Fund. Foreign exchange rate risk relates to fluctuations in the value of an asset or liability due to changes in currency exchange rates. Equity risk relates to the fluctuations in the value of financial instruments as a result of changes in market prices (other than those arising from interest rate risk or foreign exchange risk), whether caused by factors specific to an individual investment, its issuer, or all factors affecting all instruments traded in a market or market segment. Commodity risk relates to the risk that the value of a commodity or commodity index will fluctuate based on increases or decreases in the commodities market and factors specific to a particular industry or commodity. The fair value of open derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) by risk exposure at October 31, 2015, was as follows: -------------------------------------------------------------------------------- Statement of Assets and Liabilities Foreign Interest Credit Exchange Equity Commodity Rate Risk Risk Rate Risk Risk Risk -------------------------------------------------------------------------------- Assets Unrealized appreciation on swap contracts $ -- $3,954 $ -- $ -- $ -- -------------------------------------------------------------------------------- Total Value $ -- $3,954 $ -- $ -- $ -- ================================================================================ Liabilities Unrealized depreciation on swap contracts $ -- $ -- $ -- $ -- $ -- -------------------------------------------------------------------------------- Total Value $ -- $ -- $ -- $ -- $ -- ================================================================================ 62 Pioneer Floating Rate Fund | Annual Report | 10/31/15 The effect of derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) on the Statement of Operations by risk exposure at October 31, 2015, was as follows: -------------------------------------------------------------------------------- Statement of Operations Foreign Interest Credit Exchange Equity Commodity Rate Risk Risk Rate Risk Risk Risk -------------------------------------------------------------------------------- Net realized gain (loss) on Swap contracts $ -- $4,087 $ -- $ -- $ -- -------------------------------------------------------------------------------- Total Value $ -- $4,087 $ -- $ -- $ -- ================================================================================ Change in net unrealized appreciation (depreciation) on Swap contracts $ -- $3,954 $ -- $ -- $ -- -------------------------------------------------------------------------------- Total Value $ -- $3,954 $ -- $ -- $ -- ================================================================================ 9. Bridge and Delayed Draw Loan Commitments Bridge loans are designed to provide temporary or "bridge" financing to a borrower pending the sale of identified assets or the arrangement of longer- term loans or the issuance and sale of debt obligations. As of October 31, 2015, the Fund had the following bridge loan and delayed draw loan commitments outstanding as of October 31, 2015: -------------------------------------------------------------------------------- Unrealized Appreciation/ Loan Shares Cost Value Depreciation -------------------------------------------------------------------------------- Charter Communications Operating LLC, Bridge Loan 565,217 $565,217 $565,217 $ -- Integro Limited, Bridge Term Loan 347,222 333,393 336,805 3,412 -------------------------------------------------------------------------------- Total 912,439 $898,610 $902,022 $3,412 ================================================================================ 10. Conversion of Class Z Shares As of the close of business on August 7, 2015, all outstanding Class Z shares of the Fund were converted to Class Y shares. Pioneer Floating Rate Fund | Annual Report | 10/31/15 63 Report of Independent Registered Public Accounting Firm To the Board of Trustees of Pioneer Series Trust VI and the Shareowners of Pioneer Floating Rate Fund: -------------------------------------------------------------------------------- We have audited the accompanying statement of assets and liabilities, including the schedule of investments, of Pioneer Floating Rate Fund (one of the funds constituting Pioneer Series Trust VI), as of October 31, 2015, and the related statement of operations for the year then ended and the statements of changes in net assets and the financial highlights for each of the two years in the period then ended. These financial statements and financial highlights are the responsibility of the Fund's management. Our responsibility is to express an opinion on these financial statements and financial highlights based on our audits. The financial highlights for the years ended October 31, 2013, 2012, and 2011 were audited by other auditors. Those auditors expressed an unqualified opinion on those financial statements and financial highlights in their report dated December 23, 2013. We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements and financial highlights are free of material misstatement. The Fund is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. Our audits included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Fund's internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. Our procedures included confirmation of securities owned as of October 31, 2015, by correspondence with the custodian, brokers and agent banks; where replies were not received from brokers or agent banks, we performed other auditing procedures. We believe that our audits provide a reasonable basis for our opinion. In our opinion, the financial statements and financial highlights referred to above present fairly, in all material respects, the financial position of Pioneer Floating Rate Fund as of October 31, 2015, the results of its operations for the year then ended, and the changes in its net assets and the financial highlights for each of the two years in the period then ended, in conformity with accounting principles generally accepted in the United States of America. /s/ Deloitte & Touche LLP Boston, Massachusetts December 23, 2015 64 Pioneer Floating Rate Fund | Annual Report | 10/31/15 ADDITIONAL INFORMATION (unaudited) Qualified interest income is exempt from nonresident alien (NRA) tax withholding. The percentage of the Fund's ordinary income distributions derived from qualified interest income was 95.08%. PIM, the Fund's investment adviser, is currently an indirect, wholly owned subsidiary of UniCredit. On November 11, 2015, UniCredit announced that it signed a binding master agreement with Banco Santander and affiliates of Warburg Pincus and General Atlantic (the "Private Equity Firms") with respect to Pioneer Investments ("Pioneer") and Santander Asset Management ("SAM") (the "Transaction"). The Transaction, as previously announced by UniCredit, will establish a holding company, with the name Pioneer Investments, to be owned by UniCredit (50%) and the Private Equity Firms (50% between them). The holding company will control Pioneer's U.S. operations, including the Adviser. The holding company also will own 66.7% of Pioneer's and SAM's combined operations outside the U.S., while Banco Santander will own directly the remaining 33.3% stake. The closing of the Transaction is expected to happen in 2016, subject to certain regulatory and other approvals. Under the Investment Company Act of 1940, completion of the Transaction will cause the Fund's current investment advisory agreement with PIM to terminate. Accordingly, the Fund's Board of Trustees will be asked to approve a new investment advisory agreement. If approved by the Board, the Fund's new investment advisory agreement will be submitted to the shareholders of the Fund for their approval. Subsequent Event (unaudited) Effective November 2, 2015, Boston Financial Data Service became the transfer agent to the fund at negotiated rates. Pioneer Floating Rate Fund | Annual Report | 10/31/15 65 Approval of Investment Advisory Agreement Pioneer Investment Management, Inc. (PIM) serves as the investment adviser to Pioneer Floating Rate Fund (the Fund) pursuant to an investment advisory agreement between PIM and the Fund. In order for PIM to remain the investment adviser of the Fund, the Trustees of the Fund must determine annually whether to renew the investment advisory agreement for the Fund. The contract review process began in January 2015 as the Trustees of the Fund agreed on, among other things, an overall approach and timeline for the process. Contract review materials were provided to the Trustees in March 2015 and July 2015. Supplemental contract review materials were provided to the Trustees in September 2015. In addition, the Trustees reviewed and discussed the Fund's performance at regularly scheduled meetings throughout the year and took into account other information related to the Fund provided to the Trustees at regularly scheduled meetings in connection with the review of the Fund's investment advisory agreement. In March 2015, the Trustees, among other things, discussed the memorandum provided by Fund counsel that summarized the legal standards and other considerations that are relevant to the Trustees in their deliberations regarding the renewal of the investment advisory agreement, and reviewed and discussed the qualifications of the investment management teams, as well as the level of investment by the Fund's portfolio manager in the Fund. In July 2015, the Trustees, among other things, reviewed the Fund's management fee and total expense ratios, the financial statements of PIM and its parent companies, the profitability analyses provided by PIM, and possible economies of scale. The Trustees also reviewed the profitability of the institutional business of PIM and PIM's affiliate, Pioneer Institutional Asset Management, Inc. (together with PIM, "Pioneer"), as compared to that of PIM's fund management business, and considered the differences between the fees and expenses of the Fund and the fees and expenses of Pioneer's institutional accounts, as well as the different services provided by PIM to the Fund and by Pioneer to the institutional accounts. The Trustees further considered contract review materials in September 2015. At a meeting held on September 15, 2015, based on their evaluation of the information provided by PIM and third parties, the Trustees of the Fund, including the Independent Trustees voting separately, unanimously approved the renewal of the investment advisory agreement for another year. In approving the renewal of the investment advisory agreement, the Trustees 66 Pioneer Floating Rate Fund | Annual Report | 10/31/15 considered various factors that they determined were relevant, including the factors described below. The Trustees did not identify any single factor as the controlling factor in determining to approve the renewal of the agreement. Nature, Extent and Quality of Services The Trustees considered the nature, extent and quality of the services that had been provided by PIM to the Fund, taking into account the investment objective and strategy of the Fund. The Trustees also reviewed PIM's investment approach for the Fund and its research process. The Trustees considered the resources of PIM and the personnel of PIM who provide investment management services to the Fund. They also reviewed the amount of non-Fund assets managed by the portfolio manager of the Fund. The Trustees considered the non-investment resources and personnel of PIM involved in PIM's services to the Fund, including PIM's compliance and legal resources and personnel. The Trustees noted the substantial attention and high priority given by PIM's senior management to the Pioneer fund complex. The Trustees considered that PIM supervises and monitors the performance of the Fund's service providers and provides the Fund with personnel (including Fund officers) and other resources that are necessary for the Fund's business management and operations. The Trustees also considered that, as administrator, PIM is responsible for the administration of the Fund's business and other affairs. The Trustees considered the fees paid to PIM for the provision of administration services. Based on these considerations, the Trustees concluded that the nature, extent and quality of services that had been provided by PIM to the Fund were satisfactory and consistent with the terms of the investment advisory agreement. Performance of the Fund In considering the Fund's performance, the Trustees regularly review and discuss throughout the year data prepared by PIM and information comparing the Fund's performance with the performance of its peer group of funds as classified by each of Morningstar, Inc. (Morningstar) and Lipper, and with the performance of the Fund's benchmark index. They also discuss the Fund's performance with PIM on a regular basis. The Trustees' regular reviews and discussions were factored into the Trustees' deliberations concerning the renewal of the advisory agreement. Pioneer Floating Rate Fund | Annual Report | 10/31/15 67 Management Fee and Expenses The Trustees considered information showing the fees and expenses of the Fund in comparison to the management fees and expense ratios of its peer group of funds as classified by Morningstar and also to the expense ratios of a peer group of funds selected on the basis of criteria determined by the Independent Trustees for this purpose using data provided by Strategic Insight Mutual Fund Research and Consulting, LLC (Strategic Insight), an independent third party. In all quintile rankings referred to below, first quintile is most favorable to the Fund's shareowners. The Trustees considered that the Fund's management fee for the most recent fiscal year was in the second quintile relative to the management fees paid by other funds in its Morningstar peer group for the comparable period. The Trustees also considered the breakpoint in the management fee schedule and the reduced fee rate above a certain asset level. The Trustees considered that the expense ratio of the Fund's Class A shares for the most recent fiscal year was in the fourth quintile relative to its Morningstar peer group and in the third quintile relative its Strategic Insight peer group, in each case for the comparable period. The Trustees considered that the expense ratio of the Fund's Class Y shares for the most recent fiscal year was in the second quintile relative to its Morningstar peer group and in the first quintile relative its Strategic Insight peer group, in each case for the comparable period. The Trustees noted that PIM was waiving fees and/or reimbursing expenses in order to limit the ordinary operating expenses of the Fund. The Trustees considered that the expense ratio of the Fund's Class A shares was approximately two basis points higher than the median expense ratio of the funds in the Fund's Morningstar peer group. The Trustees considered the impact of transfer agency, sub-transfer agency and other non-management fee expenses on the expense ratios of the Fund, and noted the impact of expenses relating to small accounts and omnibus accounts on transfer and sub-transfer agency expenses generally. The Trustees noted that they separately review the Fund's transfer agency, sub-transfer agency and intermediary arrangements. The Trustees reviewed management fees charged by Pioneer to institutional and other clients, including publicly offered European funds sponsored by affiliates of Pioneer, unaffiliated U.S. registered investment companies (in a sub-advisory capacity), and unaffiliated foreign and domestic separate accounts. The Trustees also considered PIM's costs in providing services to the Fund and Pioneer's costs in providing services to the other clients and considered the differences in management fees and profit margins for Fund and non-Fund services. In evaluating the fees associated with Pioneer's client accounts, the Trustees took into account the respective demands, resources and complexity associated with the Fund and client accounts. The Trustees 68 Pioneer Floating Rate Fund | Annual Report | 10/31/15 noted that, in some instances, the fee rates for those clients were lower than the management fee for the Fund and considered that, under the investment advisory agreement with the Fund, PIM performs additional services for the Fund that it does not provide to those other clients or services that are broader in scope, including oversight of the Fund's other service providers and activities related to compliance and the extensive regulatory and tax regimes to which the Fund is subject. The Trustees also considered the different entrepreneurial risks associated with PIM's management of the Fund and Pioneer's management of the other client accounts. The Trustees concluded that the management fee payable by the Fund to PIM was reasonable in relation to the nature and quality of the services provided by PIM to the Fund. Profitability The Trustees considered information provided by PIM regarding the profitability of PIM with respect to the advisory services provided by PIM to the Fund, including the methodology used by PIM in allocating certain of its costs to the management of the Fund. The Trustees also considered PIM's profit margin in connection with the overall operation of the Fund. They further reviewed the financial results realized by PIM and its affiliates from non-fund businesses. The Trustees considered PIM's profit margins with respect to the Fund in comparison to the limited industry data available and noted that the profitability of any adviser was affected by numerous factors, including its organizational structure and method for allocating expenses. The Trustees concluded that PIM's profitability with respect to the management of the Fund was not unreasonable. Economies of Scale The Trustees considered PIM's views relating to economies of scale in connection with the Pioneer Funds as fund assets grow and the extent to which any such economies of scale are shared with funds and fund shareholders. The Trustees noted the breakpoint in the management fee schedule. The Trustees recognize that economies of scale are difficult to identify and quantify, and that, among other factors that may be relevant, are the following: fee levels, expense subsidization, investment by PIM in research and analytical capabilities and PIM's commitment and resource allocation to the Fund. The Trustees noted that profitability also may be an indicator of the availability of any economies of scale, although profitability may vary for other reasons including reductions in expenses. The Trustees concluded that economies of scale, if any, were being appropriately shared with the Funds. Pioneer Floating Rate Fund | Annual Report | 10/31/15 69 Other Benefits The Trustees considered the other benefits to PIM from its relationship with the Fund. The Trustees considered the character and amount of fees paid by the Fund, other than under the investment advisory agreement, for services provided by PIM and its affiliates. The Trustees further considered the revenues and profitability of PIM's businesses other than the fund business. Pioneer is the principal U.S. asset management business of Pioneer Global Asset Management, the worldwide asset management business of UniCredit Group, which manages over $150 billion in assets (including the Funds). Pioneer and the Funds receive reciprocal intangible benefits from the relationship, including mutual brand recognition and, for the Funds, direct and indirect access to the resources of a large global asset manager. The Trustees concluded that any such benefits received by Pioneer as a result of its relationship with the Funds were reasonable and their consideration of the advisory agreement between the Fund and PIM and the fees thereunder were unaffected by Pioneer's possible receipt of any such intangible benefits. Conclusion After consideration of the factors described above as well as other factors, the Trustees, including all of the Independent Trustees, concluded that the investment advisory agreement between PIM and the Fund, including the fees payable thereunder, was fair and reasonable and voted to approve the proposed renewal of the investment advisory agreement for the Fund. 70 Pioneer Floating Rate Fund | Annual Report | 10/31/15 Trustees, Officers and Service Providers Investment Adviser Pioneer Investment Management, Inc. Custodian and Sub-Administrator Brown Brothers Harriman & Co. Independent Registered Public Accounting Firm Deloitte & Touche LLP Principal Underwriter Pioneer Funds Distributor, Inc. Legal Counsel Morgan, Lewis & Bockius LLP Shareowner Services and Transfer Agent Boston Financial Data Services, Inc. Proxy Voting Policies and Procedures of the Fund are available without charge, upon request, by calling our toll free number (1-800-225-6292). Information regarding how the Fund voted proxies relating to portfolio securities during the most recent 12-month period ended June 30 is publicly available to shareowners at us.pioneerinvestments.com. This information is also available on the Securities and Exchange Commission's web site at www.sec.gov. Trustees and Officers The Fund's Trustees and officers are listed below, together with their principal occupations during at least the past five years. Trustees who are interested persons of the Fund within the meaning of the 1940 Act are referred to as Interested Trustees. Trustees who are not interested persons of the Fund are referred to as Independent Trustees. Each of the Trustees serves as a trustee of each of the 50 U.S. registered investment portfolios for which Pioneer serves as investment adviser (the "Pioneer Funds"). The address for all Trustees and all officers of the Fund is 60 State Street, Boston, Massachusetts 02109. The Statement of Additional Information of the Fund includes additional information about the Trustees and is available, without charge, upon request, by calling 1-800-225-6292. Pioneer Floating Rate Fund | Annual Report | 10/31/15 71 Independent Trustees ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Thomas J. Perna (65) Trustee since 2007. Private investor (2004 - 2008 and 2013 - present); Director, Broadridge Chairman of the Board Serves until a Chairman (2008 - 2013) and Chief Executive Officer Financial Solutions, Inc. and Trustee successor trustee (2008 - 2012), Quadriserv, Inc. (technology (investor communications and is elected or products for securities lending industry); and securities processing earlier retirement Senior Executive Vice President, The Bank of New provider for financial or removal. York (financial and securities services) (1986 - services industry) (2009 - 2004) present); Director, Quadriserv, Inc. (2005 - 2013); and Commissioner, New Jersey State Civil Service Commission (2011 - present) ------------------------------------------------------------------------------------------------------------------------------------ David R. Bock (71) Trustee since 2007. Managing Partner, Federal City Capital Advisors Director of New York Mortgage Trustee Serves until a (corporate advisory services company) (1997 - 2004 Trust (publicly-traded successor trustee and 2008 - present); Interim Chief Executive mortgage REIT) (2004 - 2009, is elected or Officer, Oxford Analytica, Inc. (privately-held 2012 - present); Director of earlier retirement research and consulting company) (2010); Executive The Swiss Helvetia Fund, Inc. or removal. Vice President and Chief Financial Officer, (closed-end fund) (2010 - I-trax, Inc. (publicly traded health care services present); Director of Oxford company) (2004 - 2007); and Executive Vice Analytica, Inc. (2008 - President and Chief Financial Officer, Pedestal present); and Director of Inc. (internet-based mortgage trading company) Enterprise Community (2000 - 2002); Private consultant (1995-1997), Investment, Inc. Managing Director, Lehman Brothers (investment (privately-held affordable banking firm) (1992-1995); and Executive, The housing finance company) World Bank (1979-1992) (1985 - 2010) ------------------------------------------------------------------------------------------------------------------------------------ Benjamin M. Friedman (71) Trustee since 2008. William Joseph Maier Professor of Political Trustee, Mellon Institutional Trustee Serves until a Economy, Harvard University (1972 - present) Funds Investment Trust and successor trustee Mellon Institutional Funds is elected or Master Portfolio (oversaw 17 earlier retirement portfolios in fund complex) or removal. (1989-2008) ------------------------------------------------------------------------------------------------------------------------------------ 72 Pioneer Floating Rate Fund | Annual Report | 10/31/15 ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Margaret B.W. Graham (68) Trustee since 2007. Founding Director, Vice President and Corporate None Trustee Serves until a Secretary, The Winthrop Group, Inc. (consulting successor trustee firm) (1982 - present); Desautels Faculty of is elected or Management, McGill University (1999 - present); earlier retirement and Manager of Research Operations and or removal. Organizational Learning, Xerox PARC, Xerox's advance research center (1990-1994) ------------------------------------------------------------------------------------------------------------------------------------ Marguerite A. Piret (67) Trustee since 2007. President and Chief Executive Officer, Newbury, Director of New America High Trustee Serves until a Piret & Company, Inc. (investment banking firm) Income Fund, Inc. (closed-end successor trustee (1981 - present) investment company) (2004 - is elected or present); and Member, Board earlier retirement of Governors, Investment or removal. Company Institute (2000 - 2006) ------------------------------------------------------------------------------------------------------------------------------------ Fred J. Ricciardi (68) Trustee since 2014. Consultant (investment company services) (2012 - None Trustee Serves until a present); Executive Vice President, BNY Mellon successor trustee (financial and investment company services) (1969 is elected or - 2012); Director, BNY International Financing earlier retirement Corp. (financial services) (2002 - 2012); and or removal. Director, Mellon Overseas Investment Corp. (financial services) (2009 - 2012) ------------------------------------------------------------------------------------------------------------------------------------ Pioneer Floating Rate Fund | Annual Report | 10/31/15 73 Interested Trustee ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Kenneth J. Taubes (57)* Trustee since 2014. Director and Executive Vice President (since 2008) None Trustee Serves until a and Chief Investment Officer, U.S. (since 2010) of successor trustee PIM-USA; Executive Vice President of Pioneer is elected or (since 2008); Executive Vice President of Pioneer earlier retirement Institutional Asset Management, Inc. (since 2009); or removal. and Portfolio Manager of Pioneer (since 1999) ------------------------------------------------------------------------------------------------------------------------------------ * Mr. Taubes is an Interested Trustee because he is an officer of the Fund's investment adviser and certain of its affiliates. 74 Pioneer Floating Rate Fund | Annual Report | 10/31/15 Advisory Trustee ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Lorraine H. Monchak (59)** Advisory Trustee Chief Investment Officer, 1199 SEIU Funds Trustee of Pioneer Advisory Trustee since 2014. (healthcare workers union pension funds) (2001 - closed-end investment present); Vice President - International companies (5 portfolios) Investments Group, American International Group, (Sept. 2015 - present) Inc. (insurance company) (1993 - 2001); Vice President Corporate Finance and Treasury Group, Citibank, N.A.(1980 - 1986 and 1990 - 1993); Vice President - Asset/Liability Management Group, Federal Farm Funding Corporation (government-sponsored issuer of debt securities) (1988 - 1990); Mortgage Strategies Group, Shearson Lehman Hutton, Inc. (investment bank) (1987 - 1988); and Mortgage Strategies Group, Drexel Burnham Lambert, Ltd. (investment bank) (1986 - 1987) ------------------------------------------------------------------------------------------------------------------------------------ ** Ms. Monchak is a non-voting advisory trustee. Pioneer Floating Rate Fund | Annual Report | 10/31/15 75 Fund Officers ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Lisa M. Jones (53) Since 2014. Serves Chair, Director, CEO and President of Pioneer Trustee of Pioneer President and Chief at the discretion Investment Management-USA (since September 2014); closed-end investment Executive Officer of the Board. Chair, Director, CEO and President of Pioneer companies (5 portfolios) Investment Management, Inc. (since September (Sept. 2015 - present) 2014); Chair, Director, CEO and President of Pioneer Funds Distributor, Inc. (since September 2014); Chair, Director, CEO and President of Pioneer Institutional Asset Management, Inc. (since September 2014); and Chair, Director, and CEO of Pioneer Investment Management Shareholder Services, Inc. (since September 2014); Managing Director, Morgan Stanley Investment Management (2010 - 2013); and Director of Institutional Business, CEO of International, Eaton Vance Management (2005 - 2010) ------------------------------------------------------------------------------------------------------------------------------------ Christopher J. Kelley (50) Since 2007. Serves Vice President and Associate General Counsel of None Secretary and Chief at the discretion Pioneer since January 2008; Secretary and Chief Legal Officer of the Board. Legal Officer of all of the Pioneer Funds since June 2010; Assistant Secretary of all of the Pioneer Funds from September 2003 to May 2010; and Vice President and Senior Counsel of Pioneer from July 2002 to December 2007 ------------------------------------------------------------------------------------------------------------------------------------ Carol B. Hannigan (54) Since 2010. Serves Fund Governance Director of Pioneer since None Assistant Secretary at the discretion December 2006 and Assistant Secretary of all the of the Board. Pioneer Funds since June 2010; Manager - Fund Governance of Pioneer from December 2003 to November 2006; and Senior Paralegal of Pioneer from January 2000 to November 2003 ------------------------------------------------------------------------------------------------------------------------------------ Thomas Reyes (52) Since 2010. Serves Senior Counsel of Pioneer since May 2013 and None Assistant Secretary at the discretion Assistant Secretary of all the Pioneer Funds of the Board. since June 2010; and Counsel of Pioneer from June 2007 to May 2013 ------------------------------------------------------------------------------------------------------------------------------------ Mark E. Bradley (55) Since 2008. Serves Vice President - Fund Treasury of Pioneer; None Treasurer and Chief at the discretion Treasurer of all of the Pioneer Funds since March Financial and of the Board. 2008; Deputy Treasurer of Pioneer from March 2004 Accounting Officer to February 2008; and Assistant Treasurer of all of the Pioneer Funds from March 2004 to February 2008 ------------------------------------------------------------------------------------------------------------------------------------ 76 Pioneer Floating Rate Fund | Annual Report | 10/31/15 ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Luis I. Presutti (50) Since 2007. Serves Director - Fund Treasury of Pioneer; and None Assistant Treasurer at the discretion Assistant Treasurer of all of the Pioneer Funds of the Board. ------------------------------------------------------------------------------------------------------------------------------------ Gary Sullivan (57) Since 2007. Serves Fund Accounting Manager - Fund Treasury of None Assistant Treasurer at the discretion Pioneer; and Assistant Treasurer of all of the of the Board. Pioneer Funds ------------------------------------------------------------------------------------------------------------------------------------ David F. Johnson (35) Since 2009. Serves Fund Administration Manager - Fund Treasury of None Assistant Treasurer at the discretion Pioneer since November 2008; Assistant Treasurer of the Board. of all of the Pioneer Funds since January 2009; and Client Service Manager - Institutional Investor Services at State Street Bank from March 2003 to March 2007 ------------------------------------------------------------------------------------------------------------------------------------ Jean M. Bradley (63) Since 2010. Serves Chief Compliance Officer of Pioneer and of all None Chief Compliance Officer at the discretion the Pioneer Funds since March 2010; Chief of the Board. Compliance Officer of Pioneer Institutional Asset Management, Inc. since January 2012; Chief Compliance Officer of Vanderbilt Capital Advisors, LLC since July 2012: Director of Adviser and Portfolio Compliance at Pioneer since October 2005; and Senior Compliance Officer for Columbia Management Advisers, Inc. from October 2003 to October 2005 ------------------------------------------------------------------------------------------------------------------------------------ Kelly O'Donnell (44) Since 2007. Serves Director - Transfer Agency Compliance of Pioneer None Anti-Money Laundering at the discretion and Anti-Money Laundering Officer of all the Officer of the Board. Pioneer Funds since 2006 ------------------------------------------------------------------------------------------------------------------------------------ Pioneer Floating Rate Fund | Annual Report | 10/31/15 77 This page for your notes. 78 Pioneer Floating Rate Fund | Annual Report | 10/31/15 This page for your notes. Pioneer Floating Rate Fund | Annual Report | 10/31/15 79 This page for your notes. 80 Pioneer Floating Rate Fund | Annual Report | 10/31/15 This page for your notes. Pioneer Floating Rate Fund | Annual Report | 10/31/15 81 This page for your notes. 82 Pioneer Floating Rate Fund | Annual Report | 10/31/15 This page for your notes. Pioneer Floating Rate Fund | Annual Report | 10/31/15 83 This page for your notes. 84 Pioneer Floating Rate Fund | Annual Report | 10/31/15 How to Contact Pioneer We are pleased to offer a variety of convenient ways for you to contact us for assistance or information. Call us for: -------------------------------------------------------------------------------- Account Information, including existing accounts, new accounts, prospectuses, applications and service forms 1-800-225-6292 FactFone(SM) for automated fund yields, prices, account information and transactions 1-800-225-4321 Retirement plans information 1-800-622-0176 Write to us: -------------------------------------------------------------------------------- Pioneer Funds P.O. Box 55014 Boston, Massachusetts 02205-5014 Our toll-free fax 1-800-225-4240 Our internet e-mail address ask.pioneer@pioneerinvestments.com (for general questions about Pioneer only) Visit our web site: us.pioneerinvestments.com This report must be preceded or accompanied by a prospectus. The Fund files a complete schedule of investments with the Securities and Exchange Commission for the first and third quarters for each fiscal year on Form N-Q. Shareholders may view the filed Form N-Q by visiting the Commission's web site at www.sec.gov. The filed form may also be viewed and copied at the Commission's Public Reference Room in Washington, DC. Information regarding the operations of the Public Reference Room may be obtained by calling 1-800-SEC-0330. [LOGO] PIONEER Investments(R) Pioneer Investment Management, Inc. 60 State Street Boston, MA 02109 us.pioneerinvestments.com Securities offered through Pioneer Funds Distributor, Inc. 60 State Street, Boston, MA 02109 Underwriter of Pioneer Mutual Funds, Member SIPC (C) 2015 Pioneer Investments 21401-08-1215 Pioneer Flexible Opportunities Fund (Formerly Pioneer Multi Asset Real Return Fund)* -------------------------------------------------------------------------------- Annual Report | October 31, 2015 -------------------------------------------------------------------------------- Ticker Symbols: Class A PMARX Class C PRRCX Class R MUARX Class Y PMYRX * Effective June 1, 2015, the Fund was renamed Pioneer Flexible Opportunities Fund. [LOGO] PIONEER Investments(R) visit us: us.pioneerinvestments.com Table of Contents President's Letter 2 Portfolio Management Discussion 4 Portfolio Summary 9 Prices and Distributions 10 Performance Update 11 Comparing Ongoing Fund Expenses 15 Schedule of Investments 17 Consolidated Financial Statements 34 Consolidated Notes to Financial Statements 42 Report of Independent Registered Public Accounting Firm 60 Approval of Investment Advisory Agreement 62 Trustees, Officers and Service Providers 67 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 1 President's Letter Dear Shareholder, Through the first three quarters of 2015, global markets experienced pockets of higher-than-average volatility due to significant cross-currents from different geographic regions. All year, investors focused on the Federal Reserve System's (the Fed's) deliberations over when to begin normalizing interest rates. However, while there were signs of gradual economic improvement in the U.S., economies abroad increasingly diverged. In June, for example, investors grew concerned about the debt crisis in Greece. That news, in turn, was followed by evidence of an economic slowdown in China, which only served to exacerbate existing worries about growth trends in the emerging markets, a segment of the global economy already being negatively impacted by slumping commodity prices, including the price of crude oil, which has been in near-steady decline for almost a year. Through September 30, 2015, the pockets of height ened market volatility alluded to above had resulted in the Standard & Poor's 500 Index turning in a negative (-5.27%) return over the first nine months of the year. However, the S&P 500 recovered nicely in October, returning 8.43% for the month, which boosted the index's year-to-date return into positive territory, at 2.71%. Despite the headwinds still vexing the global economy, our longer-term view of the U.S. economy has remained positive. Economic conditions in the U.S. have generally been constructive, based largely on improvements in employment statistics and an uptick in the housing sector, which has aided the consumer side of the economy, where household spending has been rising modestly. U.S. consumers also stand to benefit, potentially, from lower energy prices as the winter weather approaches. We continue to believe the U.S. economy remains on a slow, steady growth trend, and that it is unlikely to be disrupted by a slow pace of interest-rate normalization by the Fed. Pioneer Investments believes that investors in today's environment can potentially benefit from the consistent and disciplined investment approach we have used since our founding in 1928. We focus on identifying value across global markets using proprietary research, careful risk management, and a long-term perspective. Our ongoing goal is to produce compelling returns consistent with the stated objectives of our investment products, and with our shareowners' expectations. We believe our shareowners can benefit from the experience and tenure of our investment teams as well as the insights generated from our extensive research process. 2 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 As always, and particularly during times of market uncertainty, we encourage you to work with your financial advisor to develop an overall investment plan that addresses both your short- and long-term goals, and to implement such a plan in a disciplined manner. We greatly appreciate your trust in us in the past and look forward to continuing to serve you in the future. Sincerely, /s/ Lisa M. Jones Lisa M. Jones President and CEO Pioneer Investment Management USA Inc. November 2, 2015 Any information in this shareowner report regarding market or economic trends or the factors influencing the Fund's historical or future performance are statements of opinion as of the date of this report. These statements should not be relied upon for any other purposes. Past performance is no guarantee of future results, and there is no guarantee that market forecasts discussed will be realized. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 3 Portfolio Management Discussion | 10/31/15 In the following discussion, Michele Garau and Howard Weiss review recent market events and describes the factors that affected the performance of Pioneer Flexible Opportunities Fund* during the 12-month period ended October 31, 2015. Mr. Garau, a senior vice president and portfolio manager at Pioneer, is responsible for the day-to-day management of the Fund, along with Mr. Weiss, a vice president and portfolio manager at Pioneer. Q How did the Fund perform during the 12-month period ended October 31, 2015? A Pioneer Flexible Opportunities Fund's Class A shares returned 2.85% at net asset value during the 12-month period ended October 31, 2015, while the Fund's benchmark, the Barclays U.S. Treasury TIPS 1-10 Year Index (the Barclays Index), returned -1.24%. During the same period, the average return of the 313 mutual funds in Lipper's Alternative Global Macro Funds category was -3.95%, and the average return of the 327 mutual funds in Morningstar's Tactical Allocation Funds category was -3.60%. Q Could you discuss some of the investment decisions that factored into the Fund's benchmark-relative performance during the 12-month period ended October 31, 2015? A In managing the Fund during the period, we retained a preference for equities and had less emphasis on bonds and commodity-linked investments, based on our belief that stocks were continuing to offer the most attractive long-term return prospects, despite elevated volatility in the equity markets over the second half of the 12-month period. As of October 31, 2015, the portfolio had allocations of roughly 65% in stocks, 25% in fixed-income investments, and 10% in investments that gave the Fund exposure to "real" assets, which include real estate investment trusts (REITs) and commodities. The positioning was beneficial to Fund performance given equities' strong returns relative to both commodities and bonds during the period -- particularly the Treasury Inflation Protected Securities held in the Barclays Index. In addition, the Fund's performance benefited from the portfolio's allocation to REITs. REITs, in general, and Asian REITs, in particular, performed well over the 12 months due to the combination of their above- average yields and the overall strength in global property markets. Benchmark-relative performance received a further boost from our decision to hold little-to-no commodity-linked investments in the portfolio throughout the course of the year, which enabled the Fund to sidestep the impact of the significant underperformance of the asset class. * Note to Shareholders: Effective June 1, 2015, Pioneer Multi-Asset Real Return Fund was renamed Pioneer Flexible Opportunities Fund. 4 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Our decision to emphasize investment-grade bonds over high-yield debt within the Fund's fixed-income portfolio was another positive contributor to relative performance. High-yield bonds underperformed investment-grade bonds by a wide margin during the 12-month period, reflecting the combined impact of falling commodity prices and rising investor risk-aversion. On the negative side, the Fund's allocation to international equities detracted from performance, somewhat, as stocks in both the developed and emerging markets lagged U.S. equities for the 12-month period. Q Could you discuss the Fund's overall positioning as of October 31, 2015, and touch upon any adjustments you made during the 12-month period? A The Fund's asset allocation embodies our long-term investment orientation, and we feel that present global market conditions have not shifted to the point where they would warrant our undertaking a broad-based portfolio repositioning away from equities. Our preference for equities is a reflection of both the improving global economy and the rich valuations found in most segments of the global fixed-income markets. In addition, the U.S. Federal Reserve System (the Fed) has stated on many occasions that its future interest-rate increases will be gradual in nature and dependent upon incoming data. We believe those factors, together with the continued strength in corporate profit margins, make the case for preferring equities over bonds. We have continued to favor the U.S. equity market over other developed international markets, but we have also sought to take advantage of select opportunities in Europe and Japan. We have found a number of attractive investment candidates in the aerospace/defense sector, and in companies that are making shareholder-friendly capital allocation decisions in the form of dividends and share buybacks. The Fund also has sizable exposure to the Chinese market in the form of "H"-shares listed in Hong Kong. As is the case elsewhere, our investment approach with regard to China remains top-down and theme-driven. We have emphasized holding the stocks of companies that we feel are primed to benefit from China's transition to an economy that is more reliant on domestic consumption, and less dependent on fixed-asset investment and government spending. At the same time, we have steered the portfolio's emerging markets exposure away from countries that we believe are likely to be hurt by the very same shift. The net impact of the changes has been a reduction in the Fund's weighting in the emerging markets: Chinese investments made up approximately half of the allocation at the close of the period, with holdings in India, the Philippines and Vietnam making up the remainder of the emerging markets position. The portfolio's current positioning within fixed-income is geared primarily toward capitalizing on specific opportunities in bond sectors where investors' fears caused yields to rise to attractive levels in relation to the Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 5 underlying risks. For instance, we have invested the Fund in the bonds of certain mining and energy companies where cash flows remain more than sufficient to make the required debt payments, but where the broader downturn in commodities has caused bond prices to fall to distressed levels. We have also identified what we believe to be a potential opportunity in U.S. dollar-denominated paper in large Russian companies such as Lukoil, Gazprom, and others. We believe those securities offer very attractive yields for relatively low default risk. In addition, the portfolio holds the sovereign debt of emerging markets nations where we have seen favorable country-specific opportunities, such as Indonesia and Mexico. The Fund's "real" asset portfolio continues to be focused almost entirely on REITs. With the exception of opportunistic positions in platinum- and palladium-related investments - the market for the latter's having received a boost from palladium's use in catalytic converters at a time of strong global auto sales - we have avoided commodity-linked investments on the basis of the unfavorable supply-and-demand equation found in most markets. In contrast, we have found REITs to be a source of both above-average income and attractive total return potential. We believe the opportunity for capital appreciation in Asian REITs has been largely realized, but we retain the Fund's allocation to that sector based on compelling yields. Q Can you discuss how you used derivatives as part of your investment strategy for the Fund during the 12-month period ended October 31, 2015, and how the use of derivatives affected performance, if at all? A The impact of derivatives on the Fund's performance during the 12-month period was positive; however, our goal in using derivatives (outside of commodity-linked instruments) isn't to add to the Fund's total return. In other words, the derivative positions in the portfolio are not intended to represent high-risk investments in certain market segments. Instead, we use derivatives to maintain balance in the portfolio and as an attempt to "hedge" (or mitigate) the risks of certain other positions. Q Do you have any closing thoughts for investors? A We continue to employ a flexible, go-anywhere investment approach that we believe enables the Fund to adapt to changing market conditions by investing in any asset class or region. Rather than being constrained by a "style box" or an index-tracking strategy, we have the ability to actively seek investment opportunities while attempting to manage the Fund's risk in response to the constantly evolving market environment. Our goal in employing this approach is to seek to help the Fund's shareholders to maintain their purchasing power over time. 6 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Please refer to the Schedule of Investments on pages 17-33 for a full listing of Fund securities. All investments are subject to risk, including the possible loss of principal. The Fund has the ability to invest in a wide variety of securities and asset classes. In addition, the Fund is non-diversified, which means it can invest a higher percentage of its assets in the securities of any one or more issuers. This will increase the Fund's potential risk exposure. The Fund may invest in underlying funds (including ETFs). In addition to the Fund's operating expenses, you will indirectly bear the operating expenses of investments in any underlying funds. The Fund and some of the underlying funds employ leverage through the use of derivatives, which increases the volatility of investment returns and subjects the Fund to magnified losses if the Fund or an underlying fund's investments decline in value. The Fund and some of the underlying funds may use derivatives, such as options and futures, which can be illiquid, may disproportionately increase losses, and have a potentially large impact on Fund performance. The Fund and some of the underlying funds may employ short selling, a speculative strategy. Unlike the possible loss on a security that is purchased, there is no limit to the amount of loss on an appreciating security that is sold short. The Fund may invest in inflation-linked securities. As inflationary expectations increase, inflation-linked securities may become more attractive, because they protect future interest payments against inflation. Conversely, as inflationary concerns decrease, inflation-linked securities will become less attractive and less valuable. The Fund may invest in credit default swaps, which may in some cases be illiquid, 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. The Fund may invest in subordinated securities which may be disproportionately adversely affected by a default or even a perceived decline in creditworthiness of the issuer. The Fund may invest in floating rate loans. The value of collateral, if any, securing a floating rate loan can decline or may be insufficient to meet the issuer's obligations or may be difficult to liquidate. The Fund may invest in event-linked bonds. The return of principal and the payment of interest on event-linked bonds are contingent on the non-occurrence of a pre-defined "trigger" event, such as a hurricane or an earthquake of a specific magnitude. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 7 The Fund may invest in commodity-linked derivatives. The value of commodity-linked derivatives may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, factors affecting a particular industry or commodity, international economic, political and regulatory developments, supply and demand, and governmental regulatory policies. Investments in equity securities are subject to price fluctuation. Small-and mid-cap stocks involve greater risks and volatility than large-cap stocks. International investments are subject to special risks, including currency fluctuations, and social, economic and political uncertainties, which could increase volatility. These risks are magnified in emerging markets. Investments in fixed-income securities involve interest rate, credit, inflation, and reinvestment risks. As interest rates rise, the value of fixed-income securities will generally fall. Prepayment risk is the chance that an issuer may exercise its right to repay its security, if falling interest rates prompt the issuer to do so. Forced to reinvest the unanticipated proceeds at lower interest rates, the Fund would experience a decline in income and lose the opportunity for additional price appreciation. The Fund may invest in mortgage-backed securities, which during times of fluctuating interest rates may increase or decrease more than other fixed- income securities. Mortgage-Backed securities are also subject to prepayments. High-yield bonds possess greater price volatility, illiquidity, and possibility of default. These risks may increase share price volatility. There is no assurance that these and other strategies used by the Fund or underlying funds will be successful. Please see the prospectus for a more complete discussion of the Fund's risks. Before investing, consider the product's investment objectives, risks, charges and expenses. Contact your advisor or Pioneer Investments for a prospectus or summary prospectus containing this information. Read it carefully. Any information in this shareholder report regarding market or economic trends or the factors influencing the Fund's historical or future performance are statements of opinion as of the date of this report. Past performance is no guarantee of future results. 8 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Portfolio Summary | 10/31/15 Sector Distribution -------------------------------------------------------------------------------- (As a percentage of total long-term holdings) [THE FOLLOWING DATA WAS REPRESENTED AS A PIE CHART IN THE PRINTED MATERIAL] Financials 29.7% Industrials 18.8% Health Care 13.3% Consumer Discretionary 7.6% Materials 7.0% Information Technology 5.9% Consumer Staples 4.6% Exchange Traded Funds 4.4% Energy 3.9% Government 2.0% Utilities 1.9% Telecommunications Services 0.9% Portfolio Diversification* -------------------------------------------------------------------------------- (As a percentage of total investment portfolio) [THE FOLLOWING DATA WAS REPRESENTED AS A PIE CHART IN THE PRINTED MATERIAL] International Common Stocks 39.6% U.S. Common Stocks 30.8% International Corporate Bonds 9.6% Foreign Government Bonds 7.2% U.S. Corporate Bonds 4.4% Exchange Traded Funds 4.5% Depositary Receipts for International Stocks 3.0% Senior Secured Loans 0.6% Collateralized Mortgage Obligations 0.3% U.S. Preferred Stocks 0.0%+ + Amount rounds to less than 0.1%. * Includes investments in insurance linked securities totaling 0.1% of total investment portfolio. 10 Largest Holdings -------------------------------------------------------------------------------- (As a percentage of total long-term holdings)** 1. Russian Foreign Bond - Eurobond, 3.5%, 1/16/19 (144A) 2.79% -------------------------------------------------------------------------------- 2. Gold Fields Orogen Holdings BVI, Ltd., 4.875%, 10/7/20 (144A) 2.21 -------------------------------------------------------------------------------- 3. Indonesia Government International Bond, 5.875%, 1/15/24 (144A) 2.01 -------------------------------------------------------------------------------- 4. Mexican Bonos, 10.0%, 12/5/24 1.51 -------------------------------------------------------------------------------- 5. Raytheon Co. 1.17 -------------------------------------------------------------------------------- 6. ProShares S&P 500 Dividend Aristocrats ETF 1.16 -------------------------------------------------------------------------------- 7. ACE, Ltd. 1.10 -------------------------------------------------------------------------------- 8. Abbott Laboratories 1.09 -------------------------------------------------------------------------------- 9. American International Group, Inc. 1.08 -------------------------------------------------------------------------------- 10. Honeywell International, Inc. 1.07 -------------------------------------------------------------------------------- ** This list excludes temporary cash investments and derivative instruments. The portfolio is actively managed, and current holdings may be different. The holdings listed should not be considered recommendations to buy or sell any security listed. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 9 Prices and Distributions | 10/31/15 Net Asset Value per Share -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- Class 10/31/15 10/31/14 -------------------------------------------------------------------------------- A $12.68 $12.94 -------------------------------------------------------------------------------- C $12.56 $12.78 -------------------------------------------------------------------------------- R $12.69 $12.92 -------------------------------------------------------------------------------- Y $12.72 $12.97 -------------------------------------------------------------------------------- Distributions per Share: 11/1/14 - 10/31/15 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- Short-Term Long-Term Class Dividends Capital Gains Capital Gains -------------------------------------------------------------------------------- A $0.2973 $ -- $0.3264 -------------------------------------------------------------------------------- C $0.1604 $ -- $0.3264 -------------------------------------------------------------------------------- R $0.1464 $ -- $0.3264 -------------------------------------------------------------------------------- Y $0.3325 $ -- $0.3264 -------------------------------------------------------------------------------- The Barclays U.S. Treasury TIPS 1-10 Year Index is an unmanaged index comprised of U.S. Treasury Inflation Protected Securities (TIPS) having a maturity of at least 1 year and less than 10 years. Index returns are calculated monthly, assume reinvestment of dividends and, unlike Fund returns, do not reflect any fees, expenses or sales charges. It is not possible to invest directly in an index. The index defined here pertains to the "Value of $10,000 Investment" and "Value of $5 Million Investment" charts on pages 11-14. 10 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Performance Update | 10/31/15 Class A Shares Investment Returns -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Class A shares of Pioneer Flexible Opportunities Fund at public offering price during the periods shown, compared to that of the Barclays U.S. Treasury TIPS 1-10 Year Index. Average Annual Total Returns (As of October 31, 2015) -------------------------------------------------------------------------------- Barclays Net Public U.S. Treasury Asset Offering TIPS Value Price 1-10 Year Period (NAV) (POP) Index -------------------------------------------------------------------------------- Life-of-Class (5/3/10) 7.20% 6.30% 2.19% 5 Years 6.63 5.65 1.47 1 Year 2.85 -1.78 -1.24 -------------------------------------------------------------------------------- Expense Ratio (Per prospectus dated March 1, 2015) -------------------------------------------------------------------------------- Gross Net -------------------------------------------------------------------------------- 1.27% 1.24% -------------------------------------------------------------------------------- [THE FOLLOWING DATA WAS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL] Value of $10,000 Investment Pioneer Flexible Barclays U.S. Treasury Opportunties Fund TIPS 1-10 Year Index 5/10 $ 9,550 $10,000 10/10 $10,351 $10,481 10/11 $11,034 $11,217 10/12 $11,918 $11,797 10/13 $13,672 $11,351 10/14 $13,870 $11,419 10/15 $14,265 $11,277 Call 1-800-225-6292 or visit us.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. NAV results represent the percent change in net asset value per share. Returns would have been lower had sales charges been reflected. POP returns reflect deduction of maximum 4.50% sales charge. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The net expense ratio reflects the contractual expense limitation currently in effect through March 1, 2016, for Class A shares. There can be no assurance that Pioneer will extend the expense limitation beyond such time. Please see the prospectus for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 11 Performance Update | 10/31/15 Class C Shares Investment Returns -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Class C shares of Pioneer Flexible Opportunities Fund during the periods shown, compared to that of the Barclays U.S. Treasury TIPS 1-10 Year Index. Average Annual Total Returns (As of October 31, 2015) -------------------------------------------------------------------------------- Barclays U.S. Treasury TIPS If If 1-10 Year Period Held Redeemed Index -------------------------------------------------------------------------------- Life-of-Class (5/3/10) 6.39% 6.39% 2.19% 5 Years 5.80 5.80 1.47 1 Year 2.12 2.12 -1.24 -------------------------------------------------------------------------------- Expense Ratio (Per prospectus dated March 1, 2015) -------------------------------------------------------------------------------- Gross -------------------------------------------------------------------------------- 2.01% -------------------------------------------------------------------------------- [THE FOLLOWING DATA WAS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL] Value of $10,000 Investment Pioneer Flexible Barclays U.S. Treasury Opportunties Fund TIPS 1-10 Year Index 5/10 $10,000 $10,000 10/10 $10,816 $10,481 10/11 $11,431 $11,217 10/12 $12,252 $11,797 10/13 $13,959 $11,351 10/14 $14,043 $11,419 10/15 $14,340 $11,277 Call 1-800-225-6292 or visit us.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. Class C shares held for less than one year are subject to a 1% contingent deferred sales charge (CDSC). "If Held" results represent the percent change in net asset value per share. Returns would have been lower had sales charges been reflected. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. 12 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Performance Update | 10/31/15 Class R Shares Investment Returns -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Class R shares of Pioneer Flexible Opportunities Fund during the periods shown, compared to that of the Barclays U.S. Treasury TIPS 1-10 Year Index. Average Annual Total Returns (As of October 31, 2015) -------------------------------------------------------------------------------- Barclays Net U.S. Treasury Asset TIPS Value 1-10 Year Period (NAV) Index -------------------------------------------------------------------------------- Life-of-Fund (5/3/10) 6.96% 2.19% 5 Years 6.37 1.47 1 Year 1.90 -1.24 -------------------------------------------------------------------------------- Expense Ratio (Per prospectus dated March 1, 2015) -------------------------------------------------------------------------------- Gross -------------------------------------------------------------------------------- 1.59% -------------------------------------------------------------------------------- [THE FOLLOWING DATA WAS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL] Value of $10,000 Investment Pioneer Flexible Barclays U.S. Treasury Opportunties Fund TIPS 1-10 Year Index 5/10 $10,000 $10,000 10/10 $10,836 $10,481 10/11 $11,551 $11,217 10/12 $12,477 $11,797 10/13 $14,309 $11,351 10/14 $14,479 $11,419 10/15 $14,754 $11,277 Call 1-800-225-6292 or visit us.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. The performance shown for Class R shares for the period prior to the commencement of operations of Class R shares on September 13, 2013, is based on the performance of Class A shares, reduced to reflect the higher distribution and service fees of Class R shares. For the period beginning September 13, 2013, the actual performance of Class R shares is reflected. Class R shares are not subject to sales charges and are available for limited groups of eligible investors, including institutional investors. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 13 Performance Update | 10/31/15 Class Y Shares Investment Returns -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $5 million investment made in Class Y shares of Pioneer Flexible Opportunities Fund during the periods shown, compared to that of the Barclays U.S. Treasury TIPS 1-10 Year Index. Average Annual Total Returns (As of October 31, 2015) -------------------------------------------------------------------------------- Barclays Net U.S. Treasury Asset TIPS Value 1-10 Year Period (NAV) Index -------------------------------------------------------------------------------- Life-of-Class (5/3/10) 7.51% 2.19% 5 years 6.93 1.47 1 Year 3.20 -1.24 -------------------------------------------------------------------------------- Expense Ratio (Per prospectus dated March 1, 2015) -------------------------------------------------------------------------------- Gross Net -------------------------------------------------------------------------------- 1.04% 0.94% -------------------------------------------------------------------------------- [THE FOLLOWING DATA WAS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL] Value of $5 Million Investment Pioneer Flexible Barclays U.S. Treasury Opportunties Fund TIPS 1-10 Year Index 5/10 $5,000,000 $5,000,000 10/10 $5,428,135 $5,240,513 10/11 $5,801,896 $5,608,553 10/12 $6,284,926 $5,898,408 10/13 $7,231,801 $5,675,535 10/14 $7,354,846 $5,709,383 10/15 $7,590,039 $5,638,349 Call 1-800-225-6292 or visit us.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. Class Y shares are not subject to sales charges and are available for limited groups of eligible investors, including institutional investors. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The net expense ratio reflects the contractual expense limitation currently in effect through March 1, 2016, for Class Y shares. There can be no assurance that Pioneer will extend the expense limitation beyond such time. Please see the prospectus for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. 14 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Comparing Ongoing Fund Expenses As a shareowner in the Fund, you incur two types of costs: (1) ongoing costs, including management fees, distribution and/or service (12b-1) fees, and other Fund expenses; and (2) transaction costs, including sales charges (loads) on purchase payments. This example is intended to help you understand your ongoing expenses (in dollars) of investing in the Fund and to compare these costs with the ongoing costs of investing in other mutual funds. The example is based on an investment of $1,000 at the beginning of the Fund's latest six-month period and held throughout the six months. Using the Tables -------------------------------------------------------------------------------- Actual Expenses The first table below provides information about actual account values and actual expenses. You may use the information in this table, together with the amount you invested, to estimate the expenses that you paid over the period as follows: (1) Divide your account value by $1,000 Example: an $8,600 account value (divided by) $1,000 = 8.6 (2) Multiply the result in (1) above by the corresponding share class's number in the third row under the heading entitled "Expenses Paid During Period" to estimate the expenses you paid on your account during this period. Expenses Paid on a $1,000 Investment in Pioneer Flexible Opportunities Fund Based on actual returns from May 1, 2015, through October 31, 2015. -------------------------------------------------------------------------------- Share Class A C R Y -------------------------------------------------------------------------------- Beginning Account $1,000.00 $1,000.00 $1,000.00 $1,000.00 Value on 5/1/15 -------------------------------------------------------------------------------- Ending Account $ 926.24 $ 922.83 $ 922.01 $ 927.89 Value (after expenses) on 10/31/15 -------------------------------------------------------------------------------- Expenses Paid $ 5.97 $ 9.89 $ 9.88 $ 4.52 During Period* -------------------------------------------------------------------------------- * Expenses are equal to the Fund's annualized net expense ratio plus the expense ratio of the underlying funds. These combined totals were 1.23%, 2.04%, 2.04% and 0.93% for Class A, Class C, Class R and Class Y shares, respectively. These combined ratios were multiplied by the average account value over the period, and then multiplied by 184/365 (to reflect the one-half year period). Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 15 Hypothetical Example for Comparison Purposes The table below provides information about hypothetical account values and hypothetical expenses based on the Fund's actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the Fund's actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period. You may use this information to compare the ongoing costs of investing in the Fund and other funds. To do so, compare this 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of the other funds. Please note that the expenses shown in the tables are meant to highlight your ongoing costs only and do not reflect any transaction costs, such as sales charges (loads) that are charged at the time of the transaction. Therefore, the table below is useful in comparing ongoing costs only and will not help you determine the relative total costs of owning different funds. In addition, if these transaction costs were included, your costs would have been higher. Expenses Paid on a $1,000 Investment in Pioneer Flexible Opportunities Fund Based on a hypothetical 5% return per year before expenses, reflecting the period from May 1, 2015, through October 31, 2015. -------------------------------------------------------------------------------- Share Class A C R Y -------------------------------------------------------------------------------- Beginning Account $1,000.00 $1,000.00 $1,000.00 $1,000.00 Value On 5/1/15 -------------------------------------------------------------------------------- Ending Account $1,019.00 $1,014.92 $1,014.92 $1,020.52 Value (after expenses) On 10/31/15 -------------------------------------------------------------------------------- Expenses Paid $ 6.26 $ 10.36 $ 10.36 $ 4.74 During Period* -------------------------------------------------------------------------------- * Expenses are equal to the Fund's annualized net expense ratio plus the expense ratio of the underlying funds. These combined totals were 1.23%, 2.04%, 2.04% and 0.93% for Class A, Class C, Class R and Class Y shares, respectively. These combined ratios were multiplied by the average account value over the period, and then multiplied by 184/365 (to reflect the one-half year period). 16 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Schedule of Investments | 10/31/15 -------------------------------------------------------------------------------- Shares Value -------------------------------------------------------------------------------- PREFERRED STOCK -- 0.0%+ REAL ESTATE -- 0.0%+ Retail REIT -- 0.0%+ 204 Wheeler Real Estate Investment Trust, Inc., 9.0% $ 199,920 -------------------------------------------------------------------------------- TOTAL PREFERRED STOCK (Cost $195,245) $ 199,920 -------------------------------------------------------------------------------- COMMON STOCKS -- 66.9% MATERIALS -- 0.7% Commodity Chemicals -- 0.2% 17,941 LyondellBasell Industries NV $ 1,666,898 -------------------------------------------------------------------------------- Construction Materials -- 0.2% 97,096 Summit Materials, Inc. $ 2,044,842 -------------------------------------------------------------------------------- Diversified Metals & Mining -- 0.3% 91,684 MMC Norilsk Nickel PJSC $ 1,361,507 50,935 MMC Norilsk Nickel PJSC (A.D.R.) 758,932 ------------- $ 2,120,439 ------------- Total Materials $ 5,832,179 -------------------------------------------------------------------------------- CAPITAL GOODS -- 12.1% Aerospace & Defense -- 6.8% 12,160 Airbus Group SE $ 848,004 372,217 CAE, Inc. 4,199,765 678 Dassault Aviation SA 785,791 80,405 Honeywell International, Inc. 8,304,228 24,802 Huntington Ingalls Industries, Inc. 2,974,752 70,100 Magellan Aerospace Corp. 930,273 42,155 Northrop Grumman Corp. 7,914,601 77,282 Raytheon Co. 9,072,907 70,559 Safran SA 5,367,135 82,186 Thales SA 5,963,897 83,081 United Technologies Corp. 8,176,001 ------------- $ 54,537,354 -------------------------------------------------------------------------------- Construction & Engineering -- 2.0% 3,226,000 China Communications Construction Co., Ltd. $ 4,462,056 2,815,500 China Railway Construction Corp., Ltd. 4,235,747 3,642,000 China Railway Group, Ltd. 3,467,945 1,310,000 China State Construction International Holdings, Ltd. 1,994,478 182,000 Shimizu Corp. 1,602,933 ------------- $ 15,763,159 -------------------------------------------------------------------------------- Electrical Components & Equipment -- 0.1% 668,000 Boer Power Holdings, Ltd. $ 1,092,878 -------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 17 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------- Shares Value -------------------------------------------------------------------------------- Heavy Electrical Equipment -- 1.0% 5,712,000 China High Speed Transmission Equipment Group Co., Ltd. $ 5,144,220 1,599,800 Xinjiang Goldwind Science & Technology Co., Ltd. 3,017,790 ------------- $ 8,162,010 -------------------------------------------------------------------------------- Industrial Conglomerates -- 0.5% 17,864 Danaher Corp. $ 1,666,890 1,038,880 JG Summit Holdings, Inc. 1,585,873 41,740 SM Investments Corp. 780,846 ------------- $ 4,033,609 -------------------------------------------------------------------------------- Construction & Farm Machinery & Heavy Trucks -- 0.1% 71,117 Meritor, Inc.* $ 773,042 -------------------------------------------------------------------------------- Agricultural & Farm Machinery -- 0.7% 75,763 The Toro Co. $ 5,702,681 -------------------------------------------------------------------------------- Industrial Machinery -- 0.9% 396,000 Kawasaki Heavy Industries, Ltd. $ 1,604,408 56,816 Stanley Black & Decker, Inc. 6,021,360 ------------- $ 7,625,768 ------------- Total Capital Goods $ 97,690,501 -------------------------------------------------------------------------------- COMMERCIAL SERVICES & SUPPLIES -- 2.0% Environmental & Facilities Services -- 1.3% 2,531,000 China Everbright International, Ltd. $ 4,095,110 2,578,400 Dongjiang Environmental Co., Ltd. (c) 3,981,510 3,456,000 Tianjin Capital Environmental Protection Group Co., Ltd. 2,613,047 ------------- $ 10,689,667 -------------------------------------------------------------------------------- Security & Alarm Services -- 0.5% 61,800 Secom Co., Ltd. $ 4,156,184 -------------------------------------------------------------------------------- Research & Consulting Services -- 0.2% 15,681 Teleperformance $ 1,233,694 ------------- Total Commercial Services & Supplies $ 16,079,545 -------------------------------------------------------------------------------- TRANSPORTATION -- 3.1% Airlines -- 0.8% 532,000 ANA Holdings, Inc. $ 1,596,948 1,904,000 China Eastern Airlines Corp, Ltd.* 1,230,780 1,552,000 China Southern Airlines Co., Ltd. 1,319,633 69,700 Japan Airlines Co., Ltd. 2,644,898 ------------- $ 6,792,259 -------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 18 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------- Shares Value -------------------------------------------------------------------------------- Railroads -- 1.6% 23,100 Central Japan Railway Co. $ 4,248,892 53,200 East Japan Railway Co. 5,099,830 308,000 Keisei Electric Railway Co., Ltd. 3,825,279 ------------- $ 13,174,001 -------------------------------------------------------------------------------- Highways & Railtracks -- 0.7% 3,874,000 Shenzhen Expressway Co., Ltd. $ 2,994,073 1,232,000 Yuexiu Transport Infrastructure, Ltd. 842,486 1,774,000 Zhejiang Expressway Co., Ltd. 2,192,780 ------------- $ 6,029,339 ------------- Total Transportation $ 25,995,599 -------------------------------------------------------------------------------- AUTOMOBILES & COMPONENTS -- 1.4% Auto Parts & Equipment -- 0.9% 27,371 BorgWarner, Inc. $ 1,172,026 74,360 Brembo S.p.A. 3,281,139 9,420 Delphi Automotive Plc 783,650 53,653 Faurecia 2,127,686 ------------- $ 7,364,501 -------------------------------------------------------------------------------- Automobile Manufacturers -- 0.5% 66,800 Fuji Heavy Industries, Ltd. $ 2,616,765 1,277,000 Great Wall Motor Co., Ltd. 1,561,979 ------------- $ 4,178,744 ------------- Total Automobiles & Components $ 11,543,245 -------------------------------------------------------------------------------- CONSUMER DURABLES & APPAREL -- 0.7% Home Furnishings -- 0.6% 2,496 Forbo Holding AG $ 2,842,537 1,742,000 Man Wah Holdings, Ltd. 1,995,892 ------------- $ 4,838,429 -------------------------------------------------------------------------------- Apparel, Accessories & Luxury Goods -- 0.1% 53,950 Moncler S.p.A.* $ 869,918 ------------- Total Consumer Durables & Apparel $ 5,708,347 -------------------------------------------------------------------------------- CONSUMER SERVICES -- 1.1% Hotels, Resorts & Cruise Lines -- 0.3% 453,648 Aitken Spence Hotel Holdings Plc $ 217,332 10,637 Marriott International, Inc. 816,709 121,901 Melia Hotels International SA 1,765,682 ------------- $ 2,799,723 -------------------------------------------------------------------------------- Education Services -- 0.8% 8,175,168 China Maple Leaf Educational Systems, Ltd. $ 2,710,851 The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 19 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------- Shares Value -------------------------------------------------------------------------------- Education Services -- (continued) 100,618 New Oriental Education & Technology Group, Inc. (A.D.R.) $ 2,768,001 20,838 TAL Education Group (A.D.R.)* 801,221 ------------- $ 6,280,073 ------------- Total Consumer Services $ 9,079,796 -------------------------------------------------------------------------------- MEDIA -- 0.5% Broadcasting -- 0.2% 205,405 Sun TV Network, Ltd. $ 1,243,959 -------------------------------------------------------------------------------- Cable & Satellite -- 0.3% 38,385 Comcast Corp. $ 2,403,669 ------------- Total Media $ 3,647,628 -------------------------------------------------------------------------------- RETAILING -- 2.6% Internet Retail -- 1.7% 47,718 Ctrip.com International, Ltd. (A.D.R.)* $ 4,436,342 73,663 JD.com, Inc. (A.D.R.)* 2,034,572 361,863 Vipshop Holdings, Ltd. (A.D.R.)* 7,425,429 ------------- $ 13,896,343 -------------------------------------------------------------------------------- General Merchandise Stores -- 0.5% 51,938 Target Corp. $ 4,008,575 -------------------------------------------------------------------------------- Home Improvement Retail -- 0.4% 23,671 The Home Depot, Inc. $ 2,926,682 ------------- Total Retailing $ 20,831,600 -------------------------------------------------------------------------------- FOOD & STAPLES RETAILING -- 1.5% Drug Retail -- 1.5% 61,453 CVS Health Corp. $ 6,070,327 59,600 Sundrug Co., Ltd. 3,170,239 34,000 Tsuruha Holdings, Inc. 2,709,971 ------------- $ 11,950,537 ------------- Total Food & Staples Retailing $ 11,950,537 -------------------------------------------------------------------------------- FOOD, BEVERAGE & TOBACCO -- 2.6% Distillers & Vintners -- 0.4% 24,847 Pernod Ricard SA $ 2,931,689 -------------------------------------------------------------------------------- Packaged Foods & Meats -- 1.3% 113,490 Danone SA $ 7,920,718 544,670 Universal Robina Corp. 2,335,980 ------------- $ 10,256,698 -------------------------------------------------------------------------------- Tobacco -- 0.9% 60,264 Altria Group, Inc. $ 3,644,164 13,900 Philip Morris International, Inc. 1,228,760 The accompanying notes are an integral part of these financial statements. 20 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------- Shares Value -------------------------------------------------------------------------------- Tobacco -- (continued) 54,924 Reynolds American, Inc. $ 2,653,928 ------------- $ 7,526,852 ------------- Total Food, Beverage & Tobacco $ 20,715,239 -------------------------------------------------------------------------------- HEALTH CARE EQUIPMENT & SERVICES -- 8.2% Health Care Equipment -- 4.7% 188,098 Abbott Laboratories $ 8,426,790 260,197 Boston Scientific Corp.* 4,756,401 22,421 CR Bard, Inc. 4,178,153 35,440 Edwards Lifesciences Corp.* 5,569,396 82,323 Hill-Rom Holdings, Inc. 4,337,599 103,650 Hologic, Inc.* 4,027,839 24,066 NuVasive, Inc.* 1,134,953 5,669 Straumann Holding AG 1,606,843 19,889 Stryker Corp. 1,901,786 67,714 Zeltiq Aesthetics, Inc.* 2,284,670 ------------- $ 38,224,430 -------------------------------------------------------------------------------- Health Care Distributors -- 0.5% 49,302 Cardinal Health, Inc. $ 4,052,624 -------------------------------------------------------------------------------- Health Care Services -- 0.5% 34,679 Adeptus Health, Inc. $ 2,250,320 13,210 Laboratory Corp of America Holdings* 1,621,395 ------------- $ 3,871,715 -------------------------------------------------------------------------------- Health Care Facilities -- 1.1% 57,530 Orpea $ 4,622,389 74,735 VCA, Inc.* 4,093,236 ------------- $ 8,715,625 -------------------------------------------------------------------------------- Managed Health Care -- 1.2% 37,397 Aetna, Inc. $ 4,292,428 44,540 UnitedHealth Group, Inc. 5,245,921 ------------- $ 9,538,349 -------------------------------------------------------------------------------- Health Care Technology -- 0.2% 25,412 Cerner Corp.* $ 1,684,561 ------------- Total Health Care Equipment & Services $ 66,087,304 -------------------------------------------------------------------------------- PHARMACEUTICALS, BIOTECHNOLOGY & LIFE SCIENCES -- 4.5% Biotechnology -- 1.2% 357,500 3SBio, Inc. $ 405,453 32,139 Actelion, Ltd. 4,470,212 44,016 Gilead Sciences, Inc.* 4,759,450 ------------- $ 9,635,115 -------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 21 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------- Shares Value -------------------------------------------------------------------------------- Pharmaceuticals -- 2.2% 35,794 Bristol-Myers Squibb Co. $ 2,360,614 2,174,000 CSPC Pharmaceutical Group, Ltd. 2,030,832 19,002 Dr Reddy's Laboratories, Ltd. 1,245,231 157,924 Pfizer, Inc. 5,340,990 78,400 Shionogi & Co., Ltd. 3,242,010 15,405 Yuhan Corp. 3,819,048 ------------- $ 18,038,725 -------------------------------------------------------------------------------- Life Sciences Tools & Services --1.1% 108,672 INC Research Holdings, Inc. $ 4,532,709 11,949 Lonza Group AG 1,756,334 19,073 Thermo Fisher Scientific, Inc. 2,494,367 ------------- $ 8,783,410 ------------- Total Pharmaceuticals, Biotechnology & Life Sciences $ 36,457,250 -------------------------------------------------------------------------------- BANKS -- 3.2% Diversified Banks -- 2.0% 703,250 BDO Unibank, Inc. $ 1,529,099 1,116,324 Hatton National Bank Plc 1,724,663 37,621 JPMorgan Chase & Co. 2,417,149 1,565,700 Krung Thai Bank PCL 751,853 2,454,721 Liberbank SA 1,523,809 1,786,400 Mizuho Financial Group, Inc. 3,704,676 622,417 National Development Bank Plc 988,069 68,451 Wells Fargo & Co. 3,705,937 ------------- $ 16,345,255 -------------------------------------------------------------------------------- Regional Banks -- 1.2% 93,596 First Republic Bank $ 6,112,755 375,000 The Chiba Bank, Ltd. 2,759,021 8,875 The PNC Financial Services Group, Inc. 801,058 ------------- $ 9,672,834 ------------- Total Banks $ 26,018,089 -------------------------------------------------------------------------------- DIVERSIFIED FINANCIALS -- 3.3% Multi-Sector Holdings -- 0.8% 191,820 Ayala Corp. $ 3,198,845 85,735 GT Capital Holdings, Inc. 2,408,565 ------------- $ 5,607,410 -------------------------------------------------------------------------------- Consumer Finance -- 0.4% 95,300 Hitachi Capital Corp. $ 2,759,630 -------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 22 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------- Shares Value -------------------------------------------------------------------------------- Asset Management & Custody Banks -- 1.3% 17,256 Julius Baer Group, Ltd.* $ 858,040 136,216 KKR & Co., LP 2,336,104 10,919 Leonteq AG 2,105,653 43,183 Noah Holdings, Ltd. (A.D.R.) 1,209,988 115,195 The Blackstone Group LP 3,808,347 ------------- $ 10,318,132 -------------------------------------------------------------------------------- Investment Banking & Brokerage -- 0.8% 124,149 Morgan Stanley Co. $ 4,093,193 12,829 The Goldman Sachs Group, Inc. 2,405,438 ------------- $ 6,498,631 -------------------------------------------------------------------------------- Diversified Capital Markets -- 0.2% 68,199 Rothschild & Co. $ 1,959,901 ------------- Total Diversified Financials $ 27,143,704 -------------------------------------------------------------------------------- INSURANCE -- 5.8% Life & Health Insurance -- 1.5% 430,640 Poste Italiane S.p.A. $ 3,080,895 22,171 Swiss Life Holding AG 5,298,955 189,300 The Dai-ichi Life Insurance Co., Ltd. 3,317,200 ------------- $ 11,697,050 -------------------------------------------------------------------------------- Multi-line Insurance -- 1.9% 31,195 Allianz SE* $ 5,471,246 132,136 American International Group, Inc. 8,332,496 33,110 The Hartford Financial Services Group, Inc. 1,531,669 ------------- $ 15,335,411 -------------------------------------------------------------------------------- Property & Casualty Insurance -- 2.4% 75,241 ACE, Ltd. $ 8,542,863 70,800 Sompo Japan Nipponkoa Holdings, Inc. 2,245,515 59,385 The Allstate Corp. 3,674,744 45,046 The Travelers Companies, Inc. 5,085,243 ------------- $ 19,548,365 ------------- Total Insurance $ 46,580,826 -------------------------------------------------------------------------------- REAL ESTATE -- 6.1% Diversified REIT -- 0.7% 296,988 Hibernia Real Estate Investment Trust Plc $ 442,922 4,096,200 Mapletree Greater China Commercial Trust 2,911,020 182,998 Merlin Properties Socimi SA 2,348,519 ------------- $ 5,702,461 -------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 23 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------- Shares Value -------------------------------------------------------------------------------- Mortgage REIT -- 0.3% 124,311 Starwood Property Trust, Inc. $ 2,497,408 -------------------------------------------------------------------------------- Hotel & Resort REIT -- 0.7% 316 Hoshino Resorts Real Estate Investment Trust, Inc. $ 3,395,766 3,576 Japan Hotel Real Estate Investment Trust Investment Corp. 2,491,749 ------------- $ 5,887,515 -------------------------------------------------------------------------------- Healthcare REIT -- 0.2% 1,383,000 First Real Estate Investment Trust $ 1,224,855 -------------------------------------------------------------------------------- Residential REIT -- 0.1% 30,288 Starwood Waypoint Residential Trust $ 745,085 -------------------------------------------------------------------------------- Retail REIT -- 0.3% 9,137 Simon Property Group, Inc. $ 1,840,740 74,022 Wheeler Real Estate Investment Trust, Inc. 144,343 ------------- $ 1,985,083 -------------------------------------------------------------------------------- Diversified Real Estate Activities -- 0.6% 97,600 Daiwa House Industry Co., Ltd. $ 2,584,445 81,408 DIC Asset AG 802,115 49,000 Sumitomo Realty & Development Co., Ltd. 1,625,552 ------------- $ 5,012,112 -------------------------------------------------------------------------------- Real Estate Operating Companies -- 1.1% 1,751,200 Ascendas India Trust $ 1,094,422 33,068 Deutsche EuroShop AG 1,596,705 100,941 Deutsche Wohnen AG 2,850,289 55,608 Hispania Activos Inmobiliarios SA 838,508 5,759,000 SM Prime Holdings, Inc. 2,659,534 ------------- $ 9,039,458 -------------------------------------------------------------------------------- Real Estate Development -- 1.7% 876,000 China Resources Land, Ltd. $ 2,288,785 3,304,400 Guangzhou R&F Properties Co., Ltd. 3,291,439 4,515,500 KWG Property Holding, Ltd. 3,274,297 1,624,000 Longfor Properties Co., Ltd. 2,183,382 3,226,000 Shui On Land, Ltd. 890,746 122,361 TAG Immobilien AG 1,585,817 ------------- $ 13,514,466 -------------------------------------------------------------------------------- Real Estate Services -- 0.4% 21,030 Jones Lang LaSalle, Inc. $ 3,505,911 ------------- Total Real Estate $ 49,114,354 -------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 24 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------- Shares Value -------------------------------------------------------------------------------- SOFTWARE & SERVICES -- 2.4% Internet Software & Services -- 1.7% 50,163 Alibaba Group Holding, Ltd. (A.D.R.) $ 4,205,164 58,300 COOKPAD, Inc. 1,120,643 546,871 Just Eat Plc 3,594,332 253,700 Tencent Holdings, Ltd. 4,798,774 ------------- $ 13,718,913 -------------------------------------------------------------------------------- Data Processing & Outsourced Services -- 0.7% 21,549 MasterCard, Inc. $ 2,133,136 39,322 Visa, Inc. 3,050,601 ------------- $ 5,183,737 ------------- Total Software & Services $ 18,902,650 -------------------------------------------------------------------------------- TECHNOLOGY HARDWARE & EQUIPMENT -- 2.6% Communications Equipment -- 1.0% 104,048 Harris Corp. $ 8,233,318 -------------------------------------------------------------------------------- Electronic Equipment Manufacturers -- 1.2% 937,000 China Railway Signal & Communication Corp, Ltd. $ 743,516 226,000 Shimadzu Corp. 3,548,366 4,874,000 Wasion Group Holdings, Ltd. 5,433,443 ------------- $ 9,725,325 -------------------------------------------------------------------------------- Electronic Components -- 0.4% 37,400 Alps Electric Co., Ltd. $ 1,174,415 124,700 Taiyo Yuden Co., Ltd. 1,771,909 ------------- $ 2,946,324 ------------- Total Technology Hardware & Equipment $ 20,904,967 -------------------------------------------------------------------------------- SEMICONDUCTORS & SEMICONDUCTOR EQUIPMENT -- 0.7% Semiconductor Equipment -- 0.7% 13,402,000 Xinyi Solar Holdings, Ltd. $ 5,360,523 ------------- Total Semiconductors & Semiconductor Equipment $ 5,360,523 -------------------------------------------------------------------------------- UTILITIES -- 1.8% Electric Utilities -- 0.6% 119,389 Endesa SA $ 2,660,961 22,782 Red Electrica Corp., SA 2,011,016 ------------- $ 4,671,977 -------------------------------------------------------------------------------- Gas Utilities -- 0.1% 26,273 Enagas SA $ 796,818 -------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 25 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------- Shares Value -------------------------------------------------------------------------------------------- Water Utilities -- 1.0% 5,176,000 Beijing Enterprises Water Group, Ltd. $ 4,133,908 11,066,000 CT Environmental Group, Ltd.* 3,940,720 ------------- $ 8,074,628 -------------------------------------------------------------------------------------------- Independent Power Producers & Energy Traders -- 0.1% 2,310,000 Beijing Jingneng Clean Energy Co., Ltd.* $ 804,733 ------------- Total Utilities $ 14,348,156 -------------------------------------------------------------------------------------------- TOTAL COMMON STOCKS (Cost $518,381,258) $ 539,992,039 -------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) -------------------------------------------------------------------------------------------- COLLATERALIZED MORTGAGE OBLIGATIONS -- 1.0% BANKS -- 1.0% Thrifts & Mortgage Finance -- 1.0% 3,000,000 COMM 2006-C8 Mortgage Trust, 5.377%, 12/10/46 $ 2,979,620 2,384,000 5.91 JP Morgan Chase Commercial Mortgage Securities Trust 2006-LDP7 REMICS, Floating Rate Note, 4/15/45 2,276,800 3,000,000 5.57 Morgan Stanley Capital I Trust 2007-TOP25, Floating Rate Note, 11/12/49 3,021,656 ------------- $ 8,278,076 ------------- Total Banks $ 8,278,076 -------------------------------------------------------------------------------------------- TOTAL COLLATERALIZED MORTGAGE OBLIGATIONS (Cost $8,247,759) $ 8,278,076 -------------------------------------------------------------------------------------------- CORPORATE BONDS -- 15.2% ENERGY -- 3.4% Oil & Gas Drilling -- 0.2% 1,500,000 Transocean, Inc., 5.55%, 12/15/16 $ 1,492,035 -------------------------------------------------------------------------------------------- Integrated Oil & Gas -- 1.9% 4,677,000 Lukoil International Finance BV, 4.563%, 4/24/23 (144A) $ 4,337,356 5,682,000 Lukoil International Finance BV, 6.125%, 11/9/20 (144A) 5,866,665 4,500,000 Lukoil International Finance BV, 7.25%, 11/5/19 (144A) 4,860,900 ------------- $ 15,064,921 -------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 26 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------- Oil & Gas Exploration & Production -- 1.3% 6,687,000 Gazprom OAO Via Gaz Capital SA, 3.85%, 2/6/20 (144A) $ 6,319,215 4,000,000 Gazprom OAO Via Gaz Capital SA, 6.51%, 3/7/22 (144A) 4,160,800 ------------- $ 10,480,015 ------------- Total Energy $ 27,036,971 -------------------------------------------------------------------------------------------- MATERIALS -- 7.2% Construction Materials -- 0.4% 3,000,000 Vulcan Materials Co., 7.5%, 6/15/21 $ 3,555,000 -------------------------------------------------------------------------------------------- Metal & Glass Containers -- 0.2% 1,586,000 Ball Corp., 4.0%, 11/15/23 $ 1,546,350 -------------------------------------------------------------------------------------------- Paper Packaging -- 0.4% 3,000,000 Sealed Air Corp., 5.125%, 12/1/24 (144A) $ 3,082,500 -------------------------------------------------------------------------------------------- Diversified Metals & Mining -- 2.1% 21,086,000 Gold Fields Orogen Holdings BVI, Ltd., 4.875%, 10/7/20 (144A) $ 17,079,660 -------------------------------------------------------------------------------------------- Gold -- 4.1% 7,500,000 AngloGold Ashanti Holdings Plc, 5.125%, 8/1/22 $ 6,839,062 5,500,000 AngloGold Ashanti Holdings Plc, 8.5%, 7/30/20 5,928,890 3,000,000 AngloGold Ashanti Holdings Plc, 8.5%, 7/30/20 3,233,940 7,200,000 Kinross Gold Corp., 5.125%, 9/1/21 6,476,083 7,300,000 Kinross Gold Corp., 5.125%, 9/1/21 6,566,029 4,350,000 Kinross Gold Corp., 5.95%, 3/15/24 3,572,124 ------------- $ 32,616,128 ------------- Total Materials $ 57,879,638 -------------------------------------------------------------------------------------------- CAPITAL GOODS -- 0.4% Building Products -- 0.4% 3,000,000 USG Corp., 9.75%, 1/15/18 $ 3,367,500 ------------- Total Capital Goods $ 3,367,500 -------------------------------------------------------------------------------------------- CONSUMER DURABLES & APPAREL -- 0.2% Apparel, Accessories & Luxury Goods -- 0.2% 1,943,000 Hanesbrands, Inc., 6.375%, 12/15/20 $ 2,013,434 ------------- Total Consumer Durables & Apparel $ 2,013,434 -------------------------------------------------------------------------------------------- CONSUMER SERVICES -- 0.7% Casinos & Gaming -- 0.7% 5,523,000 MGM Resorts International, 6.625%, 12/15/21 $ 5,895,802 ------------- Total Consumer Services $ 5,895,802 -------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 27 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------- FOOD, BEVERAGE & TOBACCO -- 0.4% Packaged Foods & Meats -- 0.4% 1,500,000 Smithfield Foods, Inc., 5.875%, 8/1/21 (144A) $ 1,575,000 1,500,000 Smithfield Foods, Inc., 6.625%, 8/15/22 1,605,000 ------------- $ 3,180,000 ------------- Total Food, Beverage & Tobacco $ 3,180,000 -------------------------------------------------------------------------------------------- DIVERSIFIED FINANCIALS -- 1.5% Consumer Finance -- 0.4% 3,000,000 First Cash Financial Services, Inc., 6.75%, 4/1/21 $ 2,992,500 -------------------------------------------------------------------------------------------- Asset Management & Custody Banks -- 1.1% 3,091,000 Apollo Management Holdings LP, 4.0%, 5/30/24 (144A) $ 3,107,212 2,000,000 Fifth Street Finance Corp., 4.875%, 3/1/19 2,027,084 3,800,000 Prospect Capital Corp., 5.875%, 3/15/23 3,799,020 ------------- $ 8,933,316 ------------- Total Diversified Financials $ 11,925,816 -------------------------------------------------------------------------------------------- INSURANCE -- 0.1% Reinsurance -- 0.1% 1,000,000 7.27 Northshore Re, Ltd., Floating Rate Note, 7/5/16 (Cat Bond) (144A) $ 1,024,300 ------------- Total Insurance $ 1,024,300 -------------------------------------------------------------------------------------------- REAL ESTATE -- 0.9% Diversified Real Estate Activities -- 0.4% 3,600,000 Alam Synergy Pte, Ltd., 9.0%, 1/29/19 (144A) $ 3,456,000 -------------------------------------------------------------------------------------------- Real Estate Development -- 0.5% 2,000,000 KWG Property Holding, Ltd., 8.25%, 8/5/19 $ 2,072,500 1,400,000 Sunac China Holdings, Ltd., 9.375%, 4/5/18 1,484,000 ------------- $ 3,556,500 ------------- Total Real Estate $ 7,012,500 -------------------------------------------------------------------------------------------- TELECOMMUNICATION SERVICES -- 0.2% Wireless Telecommunication Services -- 0.2% 1,500,000 Sprint Communications, Inc., 6.0%, 12/1/16 $ 1,516,875 ------------- Total Telecommunication Services $ 1,516,875 -------------------------------------------------------------------------------------------- UTILITIES -- 0.2% Independent Power Producers & Energy Traders -- 0.2% 700,000 Star Energy Geothermal Wayang Windu, Ltd., 6.125%, 3/27/20 (144A) $ 680,750 The accompanying notes are an integral part of these financial statements. 28 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------- Floating Principal Rate (b) Amount ($) (unaudited) Value -------------------------------------------------------------------------------------------- Independent Power Producers & Energy Traders -- (continued) 1,000,000 Star Energy Geothermal Wayang Windu, Ltd., 6.125%, 3/27/20 (144A) $ 972,500 ------------- $ 1,653,250 ------------- Total Utilities $ 1,653,250 -------------------------------------------------------------------------------------------- TOTAL CORPORATE BONDS (Cost $125,505,125) $ 122,506,086 -------------------------------------------------------------------------------------------- FOREIGN GOVERNMENT BONDS -- 6.8% 14,051,000 Indonesia Government International Bond, 5.875%, 1/15/24 (144A) $ 15,513,892 2,242,000 Indonesia Government International Bond, 6.75%, 1/15/44 (144A) 2,537,244 MXN 150,895,500 Mexican Bonos, 10.0%, 12/5/24 11,703,922 3,722,000 Mexico Government International Bond, 4.0%, 10/2/23 3,841,104 21,400,000 Russian Foreign Bond -- Eurobond, 3.5%, 1/16/19 (144A) 21,587,248 ------------- $ 55,183,410 -------------------------------------------------------------------------------------------- TOTAL FOREIGN GOVERNMENT BONDS (Cost $54,919,648) $ 55,183,410 -------------------------------------------------------------------------------------------- SENIOR FLOATING RATE LOAN INTEREST -- 0.0%+** TECHNOLOGY HARDWARE & EQUIPMENT -- 0.0%+ Communications Equipment -- 0.0%+ 125,790 3.25 Commscope, Inc., Tranche 4 Term Loan, 1/14/18 $ 125,298 -------------------------------------------------------------------------------------------- TOTAL SENIOR FLOATING RATE LOAN INTEREST (Cost $125,790) $ 125,298 -------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------- Shares -------------------------------------------------------------------------------------------- CLOSED-END FUNDS -- 0.2% 62,300 Blackrock Munivest Fund, Inc. $ 624,246 44,100 Blackrock Muniyield Fund, Inc. 641,655 ------------- $ 1,265,901 -------------------------------------------------------------------------------------------- TOTAL CLOSED-END FUNDS (Cost $1,140,036) $ 1,265,901 -------------------------------------------------------------------------------------------- EXCHANGE TRADED FUNDS -- 4.0% 9,600 CSOP China 5-Year Treasury Bond ETF $ 164,616 9,600 E Fund Citi Chinese Government Bond 5-10 Years Index ETF 169,942 41,792 Guggenheim S&P Global Water Index ETF 1,183,549 The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 29 Schedule of Investments | 10/31/15 (continued) -------------------------------------------------------------------------------------------- Floating Rate (b) Shares (unaudited) Value -------------------------------------------------------------------------------------------- EXCHANGE TRADED FUNDS -- (continued) 209,556 Market Vectors Vietnam ETF $ 3,554,070 34,505 PowerShares Buyback Achievers Portfolio 1,628,981 62,296 PowerShares International BuyBack Achievers Portfolio 1,679,500 179,425 ProShares S&P 500 Dividend Aristocrats ETF 8,955,102 186,015 SPDR S&P Euro Dividend Aristocrats UCITS ETF 4,279,012 102,786 SPDR S&P Global Dividend Aristocrats ETF 3,146,184 219,314 SPDR S&P UK Dividend Aristocrats UCITS ETF 4,133,172 86,547 SPDR S&P US Dividend Aristocrats UCITS ETF 3,473,997 ------------- $ 32,368,125 -------------------------------------------------------------------------------------------- TOTAL EXCHANGE TRADED FUNDS (Cost $33,724,710) $ 32,368,125 -------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------- Principal Strike Expiration Amount ($) Description Counterparty Price Date Value -------------------------------------------------------------------------------------------------- PUT OPTIONS PURCHASED -- 0.3% 9,000 100 Shares American Airlines Group, Inc. Citibank NA 43.00 12/18/15 $ 963,000 1,100 100 Shares U.S. Bond Future Option Citibank NA 155.00 11/20/15 1,031,250 -------------------------------------------------------------------------------------------------- TOTAL PUT OPTIONS PURCHASED $ 1,994,250 ------------- (Premiums paid $2,049,140) $ 1,994,250 -------------------------------------------------------------------------------------------------- CALL OPTIONS PURCHASED -- 1.5% HKD 950 Hong Kong Stock Exchange Barclays Plc 10,600.00 12/30/15 $ 2,200,209 HKD 600 Hong Kong Stock Exchange Barclays Plc 9,800.00 12/30/15 3,348,214 JPY 300 Nikkei 225 Barclays Plc 18,625.00 11/13/15 1,541,075 HKD 1,000 Hong Kong Stock Exchange Barclays Plc 10,800.00 12/30/15 1,606,369 EUR 2,000 Euro Stoxx 50 Barclays Plc 3,500.00 12/18/15 1,152,380 2,000 100 Shares S&P500 Emini Future Citibank NA 21,120.00 12/18/15 1,820,000 -------------------------------------------------------------------------------------------------- TOTAL CALL OPTIONS PURCHASED $ 11,668,247 ------------- (Premiums paid $10,952,307) $ 11,668,247 -------------------------------------------------------------------------------------------------- TOTAL INVESTMENT IN SECURITIES -- 95.9% (Cost $755,241,018) (a) $773,581,352 -------------------------------------------------------------------------------------------------- OTHER ASSETS & LIABILITIES -- 4.1% $ 33,030,664 -------------------------------------------------------------------------------------------------- TOTAL NET ASSETS -- 100.0% $806,612,016 ================================================================================================== * Non-income producing security. + Amount rounds to less than 0.1%. The accompanying notes are an integral part of these financial statements. 30 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 (144A) Security is exempt from registration under Rule 144A of the Securities Act of 1933. Such securities may be resold normally to qualified institutional buyers in a transaction exempt from registration. At October 31, 2015, the value of these securities amounted to $96,161,242 or 11.9% of total net assets. (A.D.R.) American Depositary Receipts. REMICS Real Estate Mortgage Investment Conduits. REIT Real Estate Investment Trust. (Cat Bond) Catastrophe or event linked bond. At October 31, 2015 the value of these securities amounted to $1,024,300 or 0.1% of total net assets. See Notes to Financial Statements -- 1I. ** Senior floating rate loan interests in which the Fund invests generally pay interest at rates that are periodically redetermined by reference to a base lending rate plus a premium. These base lending rates are generally (i) the lending rate offered by one or more major European banks, such as LIBOR (London InterBank Offered Rate), (ii) the prime rate offered by one or more major United States banks, (iii) the rate of a certificate of deposit or (iv) other base lending rates used by commercial lenders. The rate shown is the coupon rate at period end. (a) At October 31, 2015, the net unrealized appreciation on investments based on cost for federal income tax purposes of $762,048,493 was as follows: Aggregate gross unrealized appreciation for all investments in which there is an excess of value over tax cost $ 37,088,501 Aggregate gross unrealized depreciation for all investments in which there is an excess of tax cost over value (25,555,642) ------------ Net unrealized appreciation $ 11,532,859 ============ (b) Debt obligation with a variable interest rate. Rate shown is rate at end of period. (c) Security is valued using fair valued methods (other than prices supplied by independent pricing services). See Notes to Financial Statements -- Note 1A. NOTE: Principal amounts are denominated in U.S. Dollars unless otherwise noted: EUR Euro HKD Hong Kong Dollar JPY Japanese Yen MXN Mexican Peso Purchases and sales of securities (excluding temporary cash investments) for the year ended October 31, 2015 aggregated $2,252,868,756 and $2,324,215,876, respectively. TOTAL RETURN SWAP AGREEMENTS ---------------------------------------------------------------------------------------------------- Net Unrealized Notional Pay/ Obligation Expiration Appreciation Principal Counterparty Receive Entity/Index Coupon Date (Depreciation) ---------------------------------------------------------------------------------------------------- EUR 1,253 Societe Pay Pioneer Custom LIBOR USD 10/17/16 $329,953 Generale SA Basket 3 Month JPY 184,624 Societe Pay JPY Custom JPY 3 Month 6/14/16 26,971 Generale SA Basket + 70 bps EUR 1,172 Societe Pay EUR Custom EURIBOR 6/13/16 139,067 Generale SA Basket 3 Month +25 bps 155,416 Citibank NA Pay HACK LIBOR USD 6/10/16 (13,337) Purefunds 3 Month ISE Cyber + 40bps ---------------------------------------------------------------------------------------------------- $482,654 ==================================================================================================== The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 31 Schedule of Investments | 10/31/15 (continued) NOTE: Principal amounts are denominated in U.S. Dollars unless otherwise noted: EUR Euro JPY Japanese Yen Various inputs are used in determining the value of the Fund's investments. These inputs are summarized in the three broad levels listed below. Level 1 -- quoted prices in active markets for identical securities. Level 2 -- other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk, etc.) See Notes to Financial Statements -- Note 1A. Level 3 -- significant unobservable inputs (including the Fund's own assumptions in determining fair value of investments) See Notes to Financial Statements -- Note 1A. The following is a summary of the inputs used as of October 31, 2015, in valuing the Fund's investments: ----------------------------------------------------------------------------------------------------- Level 1 Level 2 Level 3 Total ----------------------------------------------------------------------------------------------------- Preferred Stock $ -- $ 199,920 $ -- $ 199,920 Common Stocks Commercial Services & Supplies Environmental & Facilities Services -- -- 3,981,510 3,981,510 All other common stocks 536,010,529 -- -- 536,010,529 Collateralized Mortgage Obligations -- 8,278,076 -- 8,278,076 Corporate Bonds -- 122,506,086 -- 122,506,086 Foreign Government Bonds -- 55,183,410 -- 55,183,410 Senior Floating Rate Loan Interest -- 125,298 -- 125,298 Closed-End Funds 1,265,901 -- -- 1,265,901 Exchange Traded Funds 32,368,125 -- -- 32,368,125 Put Options Purchased 1,994,250 -- -- 1,994,250 Call Options Purchased 11,668,247 -- -- 11,668,247 ----------------------------------------------------------------------------------------------------- Total $583,307,052 $ 186,292,790 $ 3,981,510 $773,581,352 ===================================================================================================== Other Financial Instruments Net unrealized depreciation on futures contracts $ (1,170,655) $ -- $ -- $ (1,170,655) Net unrealized appreciation on total return swap contracts -- 482,654 -- 482,654 ----------------------------------------------------------------------------------------------------- Total Other Financial Instruments $ (1,170,655) $ 482,654 $ -- $ (688,001) ===================================================================================================== The following is a reconciliation of assets valued using significant unobservable inputs (Level 3): -------------------------------------------------------------------------------- Common Stocks -------------------------------------------------------------------------------- Balance as of 10/31/14 $ -- Realized gain (loss)1 (87,545) Change in unrealized appreciation (depreciation)2 16,438 Purchases 5,987,955 Sales (1,935,338) Transfers in to Level 3* -- Transfers out of Level 3* -- Transfers in and out of Level 3 activity -- -------------------------------------------------------------------------------- Balance as of 10/31/15 $ 3,981,510 ================================================================================ (1) Realized gain (loss) on these securities is included in the net realized gain (loss) from investments in the Statement of Operations. The accompanying notes are an integral part of these financial statements. 32 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 (2) Unrealized appreciation (depreciation) on these securities is included in the change in unrealized appreciation (depreciation) on investments in the Statement of Operations. * Transfers are calculated on the beginning of period values. During the year ended October 31, 2015, there were no transfers between Levels 1, 2 and 3. Net change in unrealized appreciation (depreciation) of investments still held as of 10/31/15 $16,438 ------- The following is a summary of the fair valuation of certain Fund's assets and liabilities as of October 31, 2015. ----------------------------------------------------------------------------------------- Level 1 Level 2 Level 3 Total ----------------------------------------------------------------------------------------- Assets: Foreign currencies, at value $ -- $ 7,685,128 $ -- $ 7,685,128 Futures collateral -- 9,228,493 -- 9,228,493 Swap collateral -- 2,582 -- 2,582 Cash at broker -- 10,413,642 -- 10,413,642 Variation margin for futures contracts 371,443 -- -- 371,443 ----------------------------------------------------------------------------------------- Total: $371,443 $ 27,329,845 $ -- $ 27,701,288 ========================================================================================= The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 33 Statement of Assets and Liabilities | 10/31/15 (Consolidated) ASSETS: Investment in securities, at value (cost $755,241,018) $ 773,581,352 Cash 18,769,868 Foreign currencies, at value (cost $6,454,530) 7,685,128 Futures collateral 9,228,493 Swap collateral 2,582 Cash at broker 10,413,642 Receivables -- Investment securities sold 27,610,232 Fund shares sold 2,504,780 Dividends 751,144 Interest 3,159,661 Due from Pioneer Investment Management, Inc. 37,200 Variation margin on futures contracts 371,443 Net unrealized appreciation on swap contracts 482,654 Other assets 71,870 --------------------------------------------------------------------------------------- Total assets $ 854,670,049 ======================================================================================= LIABILITIES: Payables -- Investment securities purchased $ 45,160,006 Fund shares repurchased 1,292,777 Trustee fees 1,763 Distributions 654 Futures payable 4,965 Net unrealized depreciation on futures contracts 1,170,655 Due to affiliates 245,450 Accrued expenses 181,763 --------------------------------------------------------------------------------------- Total liabilities $ 48,058,033 ======================================================================================= NET ASSETS: Paid-in capital $ 756,143,933 Undistributed net investment income 1,213,219 Accumulated net realized gain on investments, futures contracts, swap contracts, written options and foreign currency transactions 32,133,846 Net unrealized appreciation on investments 18,340,334 Net unrealized depreciation on futures contracts (1,170,655) Net unrealized appreciation on swap contracts 482,654 Net unrealized depreciation on forward foreign currency contracts and other assets and liabilities denominated in foreign currencies (531,315) --------------------------------------------------------------------------------------- Total net assets $ 806,612,016 ======================================================================================= NET ASSET VALUE PER SHARE: (No par value, unlimited number of shares authorized) Class A (based on $209,000,649/16,479,747 shares) $ 12.68 Class C (based on $218,596,598/17,408,667 shares) $ 12.56 Class R (based on $120,105/9,467 shares) $ 12.69 Class Y (based on $378,894,664/29,783,052 shares) $ 12.72 MAXIMUM OFFERING PRICE: Class A ($12.68 / 95.5%) $ 13.28 ======================================================================================= The accompanying notes are an integral part of these financial statements. 34 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Statement of Operations (Consolidated) For the Year Ended 10/31/15 INVESTMENT INCOME: Dividends (net of foreign taxes withheld of $547,822) $ 11,818,025 Interest 8,368,034 -------------------------------------------------------------------------------------------------- Total investment income $ 20,186,059 -------------------------------------------------------------------------------------------------- EXPENSES: Management fees $ 5,574,383 Transfer agent fees Class A 61,105 Class C 34,657 Class R 159 Class Y 7,647 Class Z* 420 Distribution fees Class A 524,881 Class C 2,197,889 Class R 280 Shareholder communications expense 825,633 Administrative expense 250,564 Custodian fees 438,349 Registration fees 147,508 Professional fees 128,808 Printing expense 59,293 Fees and expenses of nonaffiliated Trustees 32,215 Pricing expense 14,931 Miscellaneous 520,930 -------------------------------------------------------------------------------------------------- Total expenses $ 10,819,652 Less fees waived and expenses reimbursed by Pioneer Investment Management, Inc. (562,828) -------------------------------------------------------------------------------------------------- Net expenses $ 10,256,824 -------------------------------------------------------------------------------------------------- Net investment income $ 9,929,235 -------------------------------------------------------------------------------------------------- REALIZED AND UNREALIZED GAIN (LOSS) ON INVESTMENTS, FUTURES CONTRACTS, WRITTEN OPTIONS, SWAP CONTRACTS AND FOREIGN CURRENCY TRANSACTIONS: Net realized gain (loss) on: Investments (net of foreign capital gains taxes of $538,418) $ 16,927,364 Futures contracts (279,065) Written options 21,144,547 Swap contracts (4,193,541) Forward foreign currency contracts and other assets and liabilities denominated in foreign currencies (639,962) $ 32,959,343 -------------------------------------------------------------------------------------------------- Change in net unrealized appreciation (depreciation) on: Investments $(26,462,791) Futures contracts (2,743,022) Written options (1,621,508) Swap contracts 482,654 Forward foreign currency contracts and other assets and liabilities denominated in foreign currencies (181,839) $(30,526,506) -------------------------------------------------------------------------------------------------- Net realized and unrealized gain on investments, futures contracts, written options, swap contracts and foreign currency transactions $ 2,432,837 -------------------------------------------------------------------------------------------------- Net increase in net assets resulting from operations $ 12,362,072 ================================================================================================== * Class Z shares converted to Class Y shares on August 7, 2015. The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 35 Statements of Changes in Net Assets (Consolidated) ------------------------------------------------------------------------------------------------- Year Ended Year Ended 10/31/15 10/31/14 ------------------------------------------------------------------------------------------------- FROM OPERATIONS: Net investment income $ 9,929,235 $ 16,604,753 Net realized gain on investments, futures contracts, written options, swap contracts and foreign currency transactions 32,959,343 21,318,392 Change in net unrealized appreciation (depreciation) on investments, futures contracts, written options, swap contracts and foreign currency transactions (30,526,506) (29,331,719) ------------------------------------------------------------------------------------------------- Net increase in net assets resulting from operations $ 12,362,072 $ 8,591,426 ------------------------------------------------------------------------------------------------- DISTRIBUTIONS TO SHAREOWNERS: Net investment income: Class A ($0.30 and $0.08 per share, respectively) $ (4,787,767) $ (2,126,642) Class C ($0.16 and $0.02 per share, respectively) (2,796,710) (327,921) Class R ($0.15 and $0.06 per share, respectively) (557) (163) Class Y ($0.33 and $0.13 per share, respectively) (9,305,033) (4,649,796) Class Z* ($0.19 and $0.06 per share, respectively) (2,220) (405) Net realized gain: Class A ($0.33 and $0.49 per share, respectively) (5,521,118) (12,531,021) Class C ($0.33 and $0.49 per share, respectively) (5,791,481) (9,636,077) Class R ($0.33 and $0.49 per share, respectively) (1,460) (388) Class Y ($0.33 and $0.49 per share, respectively) (9,576,515) (16,044,747) Class Z* ($0.33 and $0.49 per share, respectively) (3,857) (773) ------------------------------------------------------------------------------------------------- Total distributions to shareowners $ (37,786,718) $ (45,317,933) ------------------------------------------------------------------------------------------------- FROM FUND SHARE TRANSACTIONS: Net proceeds from sale of shares $ 300,297,276 $ 488,676,358 Reinvestment of distributions 31,631,974 38,216,433 Cost of shares repurchased (366,871,843) (637,695,484) ------------------------------------------------------------------------------------------------- Net decrease in net assets resulting from Fund share transactions $ (34,942,593) $ (110,802,693) ------------------------------------------------------------------------------------------------- Net decrease in net assets $ (60,367,239) $ (147,529,200) NET ASSETS: Beginning of year $ 866,979,255 $1,014,508,455 ------------------------------------------------------------------------------------------------- End of year $ 806,612,016 $ 866,979,255 ------------------------------------------------------------------------------------------------- Undistributed net investment income $ 1,213,219 $ 9,789,825 ================================================================================================= * Class Z shares converted to Class Y shares on August 7, 2015. The accompanying notes are an integral part of these financial statements. 36 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 ----------------------------------------------------------------------------------------------- Year Ended Year Ended Year Ended Year Ended 10/31/15 10/31/15 10/31/14 10/31/14 Shares Amount Shares Amount ----------------------------------------------------------------------------------------------- Class A Shares sold 5,975,840 $ 79,431,258 9,236,884 $ 120,512,989 Reinvestment of distributions 702,485 8,981,329 1,069,509 13,818,762 Less shares repurchased (7,754,295) (99,574,530) (17,916,637) (231,568,945) ----------------------------------------------------------------------------------------------- Net decrease (1,075,970) $ (11,161,943) (7,610,244) $ (97,237,194) =============================================================================================== Class C Shares sold 3,551,007 $ 46,008,975 6,190,418 $ 79,783,701 Reinvestment of distributions 541,062 6,808,756 633,418 8,101,903 Less shares repurchased (5,311,858) (67,275,117) (7,270,620) (92,694,313) ----------------------------------------------------------------------------------------------- Net decrease (1,219,789) $ (14,457,386) (446,784) $ (4,808,709) =============================================================================================== Class R Shares sold 6,047 $ 74,816 4,941 $ 64,016 Reinvestment of distributions 139 1,773 9 115 Less shares repurchased (2,453) (31,093) -- -- ----------------------------------------------------------------------------------------------- Net increase 3,733 $ 45,496 4,950 $ 64,131 =============================================================================================== Class Y Shares sold 13,280,661 $ 174,740,739 22,033,294 $ 288,180,334 Reinvestment of distributions 1,234,446 15,834,274 1,257,557 16,294,893 Less shares repurchased (15,663,576) (199,789,697) (24,310,961) (313,430,251) ----------------------------------------------------------------------------------------------- Net decrease (1,148,469) $ (9,214,684) (1,020,110) $ (8,955,024) =============================================================================================== Class Z* Shares sold 3,096 $ 41,488 10,419 $ 135,318 Reinvestment of distributions 461 5,842 59 760 Less shares repurchased (15,449) (201,406) (150) (1,975) ----------------------------------------------------------------------------------------------- Net increase (decrease) (11,892) $ (154,076) 10,328 $ 134,103 =============================================================================================== * Class Z shares converted to Class Y shares on August 7, 2015. The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 37 Financial Highlights (Consolidated) --------------------------------------------------------------------------------------------------------------------------- Year Year Year Year Year Ended Ended Ended Ended Ended 10/31/15 10/31/14 10/31/13 10/31/12 10/31/11 --------------------------------------------------------------------------------------------------------------------------- Class A Net asset value, beginning of period $ 12.94 $ 13.33 $ 11.76 $ 11.25 $ 10.63 --------------------------------------------------------------------------------------------------------------------------- Increase (decrease) from investment operations: Net investment income (loss) $ 0.17(b) $ 0.27 $ 0.21 $ 0.20 $ 0.19 Net realized and unrealized gain (loss) on investments 0.20 (0.09) 1.51 0.67 0.51 --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ 0.37 $ 0.18 $ 1.72 $ 0.87 $ 0.70 --------------------------------------------------------------------------------------------------------------------------- Distribution to shareowners: Net investment income $ (0.30) $ (0.08) $ (0.15) $ (0.36) $ (0.08) Net realized gain (0.33) (0.49) -- -- -- --------------------------------------------------------------------------------------------------------------------------- Total distributions $ (0.63) $ (0.57) $ (0.15) $ (0.36) $ (0.08) --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ (0.26) $ (0.39) $ 1.57 $ 0.51 $ 0.62 --------------------------------------------------------------------------------------------------------------------------- Net asset value, end of period $ 12.68 $ 12.94 $ 13.33 $ 11.76 $ 11.25 =========================================================================================================================== Total return* 2.85% 1.45% 14.72% 8.01% 6.60% Ratio of net expenses to average net assets (a) 1.20% 1.23% 1.20% 1.20% 1.20% Ratio of net investment income (loss) to average net assets 1.33% 1.60% 1.82% 2.19% 2.05% Portfolio turnover rate 295% 383% 288% 175% 191% Net assets, end of period (in thousands) $209,001 $227,251 $335,398 $147,163 $87,316 Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly: Total expenses to average net assets (a) 1.26% 1.23% 1.23% 1.22% 1.24% Net investment income (loss) to average net assets 1.27% 1.60% 1.79% 2.17% 2.01% =========================================================================================================================== * 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. (a) Includes interest expense of 0.00%, 0.05%, 0.00%, 0.00% and 0.00%. (b) The per share data above is based on the average shares outstanding for the period presented. The accompanying notes are an integral part of these financial statements. 38 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 --------------------------------------------------------------------------------------------------------------------------- Year Year Year Year Year Ended Ended Ended Ended Ended 10/31/15 10/31/14 10/31/13 10/31/12 10/31/11 --------------------------------------------------------------------------------------------------------------------------- Class C Net asset value, beginning of period $ 12.78 $ 13.21 $ 11.66 $ 11.15 $ 10.60 --------------------------------------------------------------------------------------------------------------------------- Increase (decrease) from investment operations: Net investment income (loss) $ 0.07(b) $ 0.13 $ 0.12 $ 0.11 $ 0.08 Net realized and unrealized gain (loss) on investments 0.20 (0.05) 1.50 0.67 0.52 --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ 0.27 $ 0.08 $ 1.62 $ 0.78 $ 0.60 --------------------------------------------------------------------------------------------------------------------------- Distribution to shareowners: Net investment income $ (0.16) $ (0.02) $ (0.07) $ (0.27) $ (0.05) Net realized gain (0.33) (0.49) -- -- -- --------------------------------------------------------------------------------------------------------------------------- Total distributions $ (0.49) $ (0.51) $ (0.07) $ (0.27) $ (0.05) --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ (0.22) $ (0.43) $ 1.55 $ 0.51 $ 0.55 --------------------------------------------------------------------------------------------------------------------------- Net asset value, end of period $ 12.56 $ 12.78 $ 13.21 $ 11.66 $ 11.15 =========================================================================================================================== Total return* 2.12% 0.60% 13.93% 7.18% 5.69% Ratio of net expenses to average net assets (a) 2.01% 1.97% 1.98% 1.95% 2.00% Ratio of net investment income (loss) to average net assets 0.52% 0.89% 1.05% 1.43% 1.25% Portfolio turnover rate 295% 383% 288% 175% 191% Net assets, end of period (in thousands) $218,597 $238,164 $251,889 $104,709 $58,471 Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly: Total expenses to average net assets (a) 2.01% 1.97% 1.98% 1.95% 2.00% Net investment income (loss) to average net assets 0.52% 0.89% 1.05% 1.43% 1.25% =========================================================================================================================== * 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. (a) Includes interest expense of 0.00%, 0.05%, 0.00%, 0.00% and 0.00%. (b) The per share data above is based on the average shares outstanding for the period presented. The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 39 Financial Highlights (Consolidated) (continued) ------------------------------------------------------------------------------------------ Year Year Ended Ended 9/13/13 to 10/31/15 10/31/14 10/31/13 ------------------------------------------------------------------------------------------ Class R Net asset value, beginning of period $ 12.92 $ 13.32 $ 12.87(a) ------------------------------------------------------------------------------------------ Increase (decrease) from investment operations: Net investment income (loss) $ 0.06(d) $ 0.15 $ 0.05 Net realized and unrealized gain (loss) on investments 0.19 0.00(b) 0.44 ------------------------------------------------------------------------------------------ Net increase (decrease) from investment operations $ 0.25 $ 0.15 $ 0.49 ------------------------------------------------------------------------------------------ Distribution to shareowners: Net investment income $ (0.15) $ (0.06) $ (0.04) Net realized gain (0.33) (0.49) -- ------------------------------------------------------------------------------------------ Total distributions $ (0.48) $ (0.55) $ (0.04) ------------------------------------------------------------------------------------------ Net increase (decrease) in net asset value $ (0.23) $ (0.40) $ 0.45 ------------------------------------------------------------------------------------------ Net asset value, end of period $ 12.69 $ 12.92 $ 13.32 ========================================================================================== Total return* 1.90% 1.19% 4.76%*** Ratio of net expenses to average net assets (c) 2.01% 1.55% 1.36%** Ratio of net investment income (loss) to average net assets 0.47% 1.40% 2.96%** Portfolio turnover rate 295% 383% 288%*** Net assets, end of period (in thousands) $ 120 $ 74 $ 10 Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly: Total expenses to average net assets (c) 2.01% 1.55% 1.36%** Net investment income (loss) to average net assets 0.47% 1.40% 2.96%** ========================================================================================== * 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. ** Annualized. *** Not annualized. (a) Class R shares beginning capital was recorded on inception date at $10.00 per share. (b) Amount rounds to less than $0.01 or $(0.01) per share. (c) Includes interest expense of 0.00%, 0.05% and 0.00%. (d) The per share data above is based on the average shares outstanding for the period presented. The accompanying notes are an integral part of these financial statements. 40 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 --------------------------------------------------------------------------------------------------------------------------- Year Year Year Year Year Ended Ended Ended Ended Ended 10/31/15 10/31/14 10/31/13 10/31/12 10/31/11 --------------------------------------------------------------------------------------------------------------------------- Class Y Net asset value, beginning of period $ 12.97 $ 13.37 $ 11.79 $ 11.29 $ 10.65 --------------------------------------------------------------------------------------------------------------------------- Increase (decrease) from investment operations: Net investment income (loss) $ 0.21(b) $ 0.27 $ 0.25 $ 0.24 $ 0.15 Net realized and unrealized gain (loss) on investments 0.20 (0.05) 1.52 0.66 0.58 --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ 0.41 $ 0.22 $ 1.77 $ 0.90 $ 0.73 --------------------------------------------------------------------------------------------------------------------------- Distribution to shareowners: Net investment income $ (0.33) $ (0.13) $ (0.19) $ (0.40) $ (0.09) Net realized gain (0.33) (0.49) -- -- -- --------------------------------------------------------------------------------------------------------------------------- Total distributions $ (0.66) $ (0.62) $ (0.19) $ (0.40) $ (0.09) --------------------------------------------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ (0.25) $ (0.40) $ 1.58 $ 0.50 $ 0.64 --------------------------------------------------------------------------------------------------------------------------- Net asset value, end of period $ 12.72 $ 12.97 $ 13.37 $ 11.79 $ 11.29 =========================================================================================================================== Total return* 3.20% 1.70% 15.07% 8.33% 6.89% Ratio of net expenses to average net assets (a) 0.90% 0.95% 0.90% 0.90% 0.90% Ratio of net investment income (loss) to average net assets 1.63% 1.92% 2.11% 2.49% 2.35% Portfolio turnover rate 295% 383% 288% 175% 191% Net assets, end of period (in thousands) $378,895 $401,336 $427,190 $185,648 $119,744 Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly: Total expenses to average net assets (a) 1.02% 1.00% 0.98% 0.91% 0.98% Net investment income (loss) to average net assets 1.52% 1.92% 2.03% 2.48% 2.67% =========================================================================================================================== * 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. (a) Includes interest expense of 0.00%, 0.05%, 0.00%, 0.00% and 0.00%. (b) The per share data above is based on the average shares outstanding for the period presented. The accompanying notes are an integral part of these financial statements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 41 Notes to Financial Statements | 10/31/15 (Consolidated) 1. Organization and Significant Accounting Policies Pioneer Flexible Opportunities Fund, (formerly Pioneer Multi Asset Real Return Fund) (the Fund), is one of two portfolios comprising Pioneer Series Trust VI, a Delaware statutory trust. The Fund is registered under the Investment Company Act of 1940 as a non-diversified, open-end management investment company. The Fund's investment objective is to seek total return. The Fund offers four classes of shares designated as Class A, Class C, Class R and Class Y shares. Class A, Class C and Class Y shares commenced operations on May 3, 2010. Class R shares commenced operations on September 13, 2013. Class Z shares converted to Class Y shares as of the close of business on August 7, 2015. Each class of shares represents an interest in the same portfolio of investments of the Fund and has identical rights (based on relative net asset values) to assets and liquidation proceeds. Share classes can bear different rates of class-specific fees and expenses such as transfer agent and distribution fees. Differences in class-specific fees and expenses will result in differences in net investment income and, therefore, the payment of different dividends from net investment income earned by each class. The Amended and Restated Declaration of Trust of the Fund gives the Board the flexibility to specify either per-share voting or dollar-weighted voting when submitting matters for shareholder approval. Under per-share voting, each share of a class of the Fund is entitled to one vote. Under dollar-weighted voting, a shareholder's voting power is determined not by the number of shares owned, but by the dollar value of the shares on the record date. Each share class has exclusive voting rights with respect to matters affecting only that class, including with respect to the distribution plan for that class. There is no distribution plan for Class Y shares. The consolidated financial statements of the Fund include the accounts of the Subsidiary. All intercompany accounts and transactions have been eliminated. The Subsidiary, a Cayman Islands exempted company, was incorporated on February 10, 2010 and is wholly-owned and controlled by the Fund. The Fund is the sole shareholder of the Subsidiary. It is intended that the Fund will remain the sole shareholder and will continue to control the Subsidiary. The Fund and the Subsidiary are both managed by PIM. The Subsidiary acts as an investment vehicle for the Fund in order to effect certain investments on behalf of the Fund. As of October 31, 2015, the Subsidiary represented $24,244,633 or approximately 3.01% of the net assets of the Fund. 42 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 The Fund's financial statements have been prepared in conformity with U.S. generally accepted accounting principles that require the management of the Fund to, among other things, make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of income, expenses and gains and losses on investments during the reporting period. Actual results could differ from those estimates. The following is a summary of significant accounting policies followed by the Fund in the preparation of its financial statements: A. Security Valuation Security transactions are recorded as of trade date. The net asset value of the Fund is computed once daily, on each day the New York Stock Exchange (NYSE) is open, as of the close of regular trading on the NYSE. Equity securities that have traded on an exchange are valued at the last sale price on the principal exchange where they are traded. Equity securities that have not traded on the date of valuation, or securities for which sale prices are not available, generally are valued using the mean between the last bid and asked prices. Fixed income securities are valued at prices supplied by independent pricing services, which consider such factors as market prices, market events, quotations from one or more brokers, Treasury spreads, yields, maturities and ratings. Valuations may be supplemented by dealers and other sources, as required. Senior floating rate loan interests (senior loans) are valued in accordance with guidelines established by the Board of Trustees at the mean between the last available bid and asked prices from one or more brokers or dealers as obtained from Loan Pricing Corporation, an independent pricing service. If price information is not available from Loan Pricing Corporation, or if the price is deemed to be unreliable, price information will be obtained from an alternate loan interest pricing service. If no reliable price quotes are available from either the primary or 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 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. Credit default swaps are valued by an independent pricing service based upon valuation models incorporating default probabilities, estimated recovery rates, actual reported transactions, and Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 43 other available market data. Shares of money market mutual funds are valued at such funds' net asset value. Cash may include overnight time deposits at approved financial institutions. Trading in foreign securities is substantially completed each day at various times prior to the close of the NYSE. The values of such securities used in computing the net asset value of the Fund's shares are determined as of such times. Securities or senior loans for which independent pricing services are unable to supply prices or for which market prices and/or quotations are not readily available or are considered to be unreliable are valued by a fair valuation team comprised of certain personnel of Pioneer Investment Management, Inc. (PIM), the Fund's investment adviser, pursuant to procedures adopted by the Fund's Board of Trustees. PIM's fair valuation team uses fair value methods approved by the Valuation Committee of the Board of Trustees. PIM's fair valuation team is responsible for monitoring developments that may impact fair valued securities and for discussing and assessing fair values on an ongoing basis, and at least quarterly, with the Valuation Committee of the Board of Trustees. Inputs used when applying fair value methods to value a security may include credit ratings, the financial condition of the company, current market conditions and comparable securities. The Valuation Committee is comprised of certain members of the Board of Trustees. The Fund may use fair value methods if it is determined that a significant event has occurred after the close of the exchange or market on which the security trades and prior to the determination of the Fund's net asset value. Examples of a significant event might include political or economic news, corporate restructurings, natural disasters, terrorist activity or trading halts. Thus, the valuation of the Fund's securities may differ significantly from exchange prices and such differences could be material. At October 31, 2015, one security was valued using a fair value method (in addition to the securities valued using prices supplied by independent pricing services or broker-dealers) representing approximately 0.5% of net assets. B. Investment Income and Transactions Principal amounts of mortgage-backed securities are adjusted for monthly paydowns. Premiums and discounts related to certain mortgage-backed securities are amortized or accreted in proportion to the monthly paydowns. All discounts/premiums on debt securities are accreted/amortized for financial reporting purposes over the life of the respective securities, and such accretion/amortization is included in interest income. 44 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Dividend income is recorded on the ex-dividend date except that certain dividends from foreign securities where the ex-dividend date may have passed are recorded as soon as the Fund becomes aware of the ex-dividend data in the exercise of reasonable diligence. Interest income is recorded on the accrual basis. All discounts/premiums on purchase prices of debt securities are accreted/amortized into interest income for financial reporting purposes. Gains and losses on sales of investments are calculated on the identified cost method for both financial reporting and federal income tax purposes. C. Foreign Currency Translation The books and records of the Fund are maintained in U.S. dollars. Amounts denominated in foreign currencies are translated into U.S. dollars using current exchange rates. Net realized gains and losses on foreign currency transactions, if any, represent, among other things, the net realized gains and losses on foreign currency contracts, disposition of foreign currencies and the difference between the amount of income accrued and the U.S. dollars actually received. Further, the effects of changes in foreign currency exchange rates on investments are not segregated in the statement of operations from the effects of changes in the market prices of those securities but are included with the net realized and unrealized gain or loss on investments. D. Futures Contracts The Fund may enter into futures transactions in order to attempt to hedge against changes in interest rates, securities prices and currency exchange rates or to seek to increase total return. Futures contracts are types of derivatives. All futures contracts entered into by the Fund are traded on a futures exchange. Upon entering into a futures contract, the Fund is required to deposit with a broker an amount of cash or securities equal to the minimum "initial margin" requirements of the associated futures exchange. The amount of cash deposited with the broker as collateral at October 31, 2015 was $9,228,493. Subsequent payments for futures contracts ("variation margin") are paid or received by the Fund, depending on the daily fluctuation in the value of the contracts, and are recorded by the Fund as unrealized gains or losses. When the contract is closed, the Fund realizes a gain or loss equal to the difference between the opening and closing value of the contract as well as any fluctuation in foreign currency exchange rates where applicable. Futures contracts are subject to market risk, interest rate risk and currency exchange rate risk. Changes in value of the contracts may not directly correlate to the changes in value of the underlying securities. With futures, Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 45 there is minimal counterparty credit risk to the Fund since futures are exchange-traded and the exchange's clearinghouse, as counterparty to all exchange-traded futures, guarantees the futures against default. The average value of contracts open during the year ended October 31, 2015 was $16,611,072. At October 31, 2015, open futures contracts were as follows: ---------------------------------------------------------------------------------------------- Number of Unrealized Contracts Settlement Appreciation/ Type Counterparty Long/(Short) Month Value (Depreciation) ---------------------------------------------------------------------------------------------- U.S. Treasury Long Bond Futures Citibank N.A. 350 12/15 $ 54,753,125 $ (282,824) H-Shares Index Futures Citibank N.A. (464) 11/15 (31,212,118) 560,111 JPY FX Futures Citibank N.A. (328) 12/15 (33,980,800) 65,600 CHF FX Futures Citibank N.A. (124) 12/15 (15,703,050) 264,275 EUR FX Futures Citibank N.A. (107) 12/15 (14,724,538) 274,188 S&P E-Mini Futures Citibank N.A. (400) 12/15 (41,474,000) (3,171,300) BP Currency Future Citibank N.A. (32) 12/15 (3,084,400) (13,000) Palladium Futures Citibank N.A. 210 12/15 14,222,250 1,310,895 Copper Futures Citibank N.A. 101 12/15 5,851,688 (178,600) ---------------------------------------------------------------------------------------------- Total $(65,351,843) $ (1,170,655) ============================================================================================== E. Forward Foreign Currency Contracts The Fund may enter into forward foreign currency contracts (contracts) for the purchase or sale of a specific foreign currency at a fixed price on a future date. All contracts are marked to market daily at the applicable exchange rates, and any resulting unrealized appreciation or depreciation is recorded in the Fund's financial statements. The Fund records realized gains and losses at the time a contract is offset by entry into a closing transaction or extinguished by delivery of the currency. Risks may arise upon entering into these contracts from the potential inability of counterparties to meet the terms of the contract and from unanticipated movements in the value of foreign currencies relative to the U.S. dollar (see Note 6). F. Federal Income Taxes It is the Fund's policy to comply with the requirements of the Internal Revenue Code applicable to regulated investment companies and to distribute all of its net taxable income and net realized capital gains, if any, to its shareowners. Therefore, no federal income tax provision is required. As of October 31, 2015, the Fund did not accrue any interest or penalties with respect to unrecognized tax positions, which, if applicable, would be recorded as an income tax expense in the Statement of Operations. Tax returns filed within the prior three years remain subject to examination by federal and state tax authorities. 46 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 The amount and character of income and capital gain distributions to shareowners are determined in accordance with federal income tax rules, which may differ from U.S. generally accepted accounting principles. Distributions in excess of net investment income or net realized gains are temporary overdistributions for financial statement purposes resulting from differences in the recognition or classification of income or distributions for financial statement and tax purposes. Capital accounts within the financial statements are adjusted for permanent book/tax differences to reflect tax character, but are not adjusted for temporary differences. At October 31, 2015, the Fund reclassified $1,613,554 to decrease undistributed net investment income, $5,187,741 to increase accumulated net realized gain on investments, futures contracts, swap contracts, written options and foreign currency transactions and $3,574,187 to decrease paid-in capital to reflect permanent book/tax differences. These adjustments have no impact on net assets or the results of operations. The tax character of distributions during the year ended October 31, 2015 and October 31, 2014 were as follows: --------------------------------------------------------------------------- 2015 2014 --------------------------------------------------------------------------- Distributions paid from: Ordinary income $16,892,287 $ 7,104,927 Long-term capital gain 20,894,431 38,213,006 --------------------------------------------------------------------------- Total $37,786,718 $45,317,933 =========================================================================== The following shows the components of distributable earnings on a federal income tax basis at October 31, 2015: --------------------------------------------------------------------------- 2015 --------------------------------------------------------------------------- Distributable earnings: Undistributed ordinary income $ 2,662,581 Undistributed long-term capital gain 35,258,195 Net unrealized appreciation 12,547,307 --------------------------------------------------------------------------- Total $50,468,083 =========================================================================== The difference between book-basis and tax-basis net unrealized appreciation is attributable to the tax deferral of losses on wash-sales, the tax treatment on passive foreign investment company (PFIC) holdings, adjustments relating to catastrophe bonds, tax basis adjustments on partnerships and the mark-to-market of forward foreign currency contracts, future contracts and options and the tax basis adjustments on partnerships. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 47 G. Fund Shares The Fund records sales and repurchases of its shares as of trade date. Pioneer Funds Distributor, Inc. (PFD), the principal underwriter for the Fund and a wholly owned indirect subsidiary of UniCredit S.p.A. (UniCredit), earned $57,224 in underwriting commissions on the sale of Class A shares during the year ended October 31, 2015. H. Class Allocations Income, common expenses and realized and unrealized gains and losses are calculated at the Fund level and allocated daily to each class of shares based on its respective percentage of adjusted net assets at the beginning of the day. Distribution fees are calculated based on the average daily net asset value attributable to Class A and Class C and Class R shares of the Fund, respectively (see Note 4). Class Y shares do not pay distribution fees. All expenses and fees paid to the Fund's transfer agent for its services are allocated among the classes of shares based on the number of accounts in each class and the ratable allocation of related out-of-pocket expenses (see Note 3). Distributions to shareowners are recorded as of the ex-dividend date. Distributions paid by the Fund with respect to each class of shares are calculated in the same manner and at the same time, except that net investment income dividends to Class A, Class C, Class R and Class Y shares can reflect different transfer agent and distribution expense rates. I. Insurance Linked Securities (ILS) Event-linked bonds are floating rate debt obligations for which the return of principal and the payment of interest are contingent on the non-occurrence of a pre-defined "trigger" event, such as a hurricane or an earthquake of a specific magnitude. The trigger event's magnitude may be based on losses to a company or industry, industry indexes or readings of scientific instruments, or may be based on specified actual losses. If a trigger event, as defined within the terms of an event-linked bond occurs, the fund may lose a portion or all of its accrued interest and/or principal invested in such event-linked bond. The fund is entitled to receive principal and interest payments so long as no trigger event occurs of the description and magnitude specified by the instrument. In addition to the specified trigger events, event-linked bonds may expose the Fund to other risks, including but not limited to issuer (credit) default, adverse regulatory or jurisdictional interpretations and adverse tax consequences. 48 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 The Fund's investments in ILS may include 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"), are subject to the same risks as event-linked bonds. In addition, because quota share instruments represent an interest in a basket 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 issuer. Accordingly, it may be more difficult for PIM to fully evaluate the underlying risk profile of the Fund's investment in quota share instruments and therefore place the Fund's assets at greater risk of loss than if PIM had more complete information. Quota share instruments and other structured reinsurance instruments generally will be considered illiquid securities by the Fund. These securities may be difficult to purchase, sell or unwind. Illiquid securities also may be difficult to value. If the Fund is forced to sell an illiquid asset, the Fund may be forced to sell at a loss. J. Risks Investing in foreign and/or emerging markets securities involves risks relating to interest rates, currency exchange rates and economic and political conditions. At times, the Fund's investments may represent industries or industry sectors that are interrelated or have common risks, making the Fund more susceptible to any economic, political, or regulatory developments or other risks affecting those industries and sectors. The Fund's prospectus contains unaudited information regarding the Fund's principal risks. Please refer to that document when considering the Fund's principal risks. The Fund may gain exposure to commodities (such as oil and precious metals) through investment in commodity-related investments, including commodity-linked derivatives, ETFs and leveraged or unleveraged commodity-linked notes (derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices). The Fund also may invest in equity securities of issuers in commodity-related industries. The Fund's investments in commodity-related investments may subject the Fund to greater market price volatility than investments in traditional securities. The value of commodity-related investments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting particular industries or commodities, such as weather, disease, embargoes, acts of war or terrorism, or political and regulatory developments. Commodity-related investments Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 49 may be more volatile than the underlying commodities. In addition, commodity-linked investments are subject to counterparty risk due to there being a relatively small number of issuers. The Fund gains exposure to commodity-related investments by investing in the Pioneer Cayman Commodity Fund, Ltd. (the Subsidiary), a foreign entity that is treated as a controlled foreign corporation for U.S. federal income tax purposes. The Fund may invest up to 25% of its total assets in the Subsidiary. The Fund's ability to invest in commodity-related investments, and the means through which any such investments may be made, is limited by tax considerations. The Fund may invest in REIT securities, the value of which can fall for a variety of reasons, such as declines in rental income, fluctuating interest rates, poor property management, environmental liabilities, uninsured damage, increased competition, or changes in real estate tax laws. K. Repurchase Agreements Repurchase agreements are arrangements under which 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 specific 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. The value of the collateral, including accrued interest, is required to be equal to or in excess of the repurchase price. The collateral for all repurchase agreements is held in safekeeping in the customer-only account of the Fund's custodian or a subcustodian of the Fund. The Fund's investment adviser, PIM is responsible for determining that the value of the collateral remains at least equal to the repurchase price. In the event of a default by the counterparty, 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 to the Fund. 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. As of the year ended October 31, 2015 the fund had no outstanding repurchase agreements. L. Option Writing The Fund may write put and covered call options to seek to increase total return. When an option is written, the Fund receives a premium and becomes obligated to purchase or sell the underlying security at a fixed price, upon the exercise of the option. When the Fund writes an option, an amount equal to the premium received by the Fund is recorded as a liability and is subsequently adjusted to the current value of the option written. Premiums received from writing options that expire unexercised are treated by the Fund on the expiration date as realized gains from investments. The difference 50 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 between the premium and the amount paid on effecting a closing purchase transaction, including brokerage commissions, is also treated as a realized gain, or, if the premium is less than the amount paid for the closing purchase transaction, as a realized loss. If a call option is exercised, the premium is added to the proceeds from the sale of the underlying security in determining whether the Fund has realized a gain or loss. The Fund as writer of an option bears the market risk of an unfavorable change in the price of the security underlying the written option. The average value of contracts open during the year ended October 31, 2015 was $(4,591,466). There were no written option contracts outstanding as of October 31, 2015. Transactions in written options for the year ended October 31, 2015 are summarized as follows: ------------------------------------------------------------------------------ Number of Contracts Premium Received ------------------------------------------------------------------------------ Options open at beginning of period (20,750) $ (5,731,258) Options opened (117,100) (84,046,342) Options exercised 109,260 66,787,880 Options closed -- -- Options expired 28,590 22,989,720 ------------------------------------------------------------------------------ Options open at end of period (--) $ (--) ============================================================================== M. Purchased Options The Fund may purchase put and call options to seek to increase total return. Purchased call and put options entitle the Fund to buy and sell a specified number of shares or units of a particular security, currency or index at a specified price at a specific date or within a specific period of time. Upon the purchase of a call or put option, the premium paid by the Fund is included in the Statement of Assets and Liabilities as an investment. All premiums are marked-to-market daily, and any unrealized appreciation or depreciation are recorded in the Fund's financial statements. As the purchaser of an index option, the Fund has the right to receive a cash payment equal to any depreciation in the value of the index below the strike price of the option (in the case of a put) or equal to any appreciation in the value of the index over the strike price of the option (in the case of a call) as of the valuation date of the option. Premiums paid for purchased calls and put options which have expired are treated as realized losses on investments in the Statement of Operations. Upon the exercise or closing of a purchased put option, the premium is offset against the proceeds on the sale of the underlying security or financial instrument in order to determine the realized gain or loss on investments. Upon the exercise or closing of a purchased call option, the premium is added to the cost of the security or financial instrument. The risk associated with purchasing options is limited to the premium originally paid. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 51 The average value of contracts open during the year ended October 31, 2015 was $17,323,126. Purchased options open at period end are listed in the Fund's Schedule of Investments. N. Credit Default Swap Agreements A credit default swap is a contract between a buyer of protection and a seller of protection against a pre-defined credit event. The Fund may sell or buy credit default swap contracts to seek to increase the Fund's income, or to attempt to hedge the risk of default on portfolio securities. A credit default swap index is used to hedge risk or take a position on a basket of credit entities or indices. As a seller of protection, the Fund would be required to pay the notional (or other agreed-upon) value of the referenced debt obligation to the counterparty in the event of a default by a U.S. or foreign corporate issuer of a debt obligation, which would likely result in a loss to the Fund. In return, the Fund would receive from the counterparty a periodic stream of payments during the term of the contract provided that no event of default occurred. The maximum exposure of loss to the seller would be the notional value of the credit default swaps outstanding. If no default occurs, the Fund would keep the stream of payments and would have no payment obligation. The Fund may also buy credit default swap contracts in order to hedge against the risk of default of debt securities, in which case the Fund would function as the counterparty referenced above. When the Fund enters into a credit default swap contract, the protection buyer makes an upfront or periodic payment to the protection seller in exchange for the right to receive a contingent payment. An upfront payment made by the Fund, as the protection buyer, is recorded as an asset in the Statement of Assets and Liabilities. Periodic payments received or paid by the Fund are recorded as realized gains or losses in the Statement of Operations. Credit default swap contracts are marked-to-market daily using valuations supplied by independent sources and the change in value, if any, is recorded as unrealized appreciation or depreciation in the Statement of Assets and Liabilities. Payments received or made as a result of a credit event or upon termination of the contract are recognized, net of the appropriate amount of the upfront payment, as realized gains or losses in the Statement of Operations. Credit default swap contracts involving the sale of protection may involve greater risks than if the Fund had invested in the referenced debt instrument directly. Credit default swap contracts are subject to general market risk, liquidity risk, counterparty risk and credit risk. If the Fund is a protection buyer and no credit event occurs, it will lose its investment. If the Fund is a protection seller and a credit event occurs, the value of the referenced debt 52 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 instrument received by the Fund, together with the periodic payments received, may be less than the amount the Fund pays to the protection buyer, resulting in a loss to the Fund. There were no open credit default swap contracts at October 31, 2015. The average value of swap contracts open during the year ended October 31, 2015 was $(281,712). O. Total Return Swap Agreements The Fund may enter into a total return swap to attempt to manage and/or gain exposure to a security or market. Pursuant to a total return swap agreement, the Fund negotiates with a counterparty to exchange a periodic stream of payments. One party makes payments based on the total return of a reference asset (such as a security or a basket of securities or securities index), and in return receives fixed or floating rate interest payments. The total return of the reference asset typically includes appreciation or depreciation on the reference asset, plus any interest or dividend payments. To the extent that the total return of the reference asset exceeds or falls short of the offsetting interest rate obligation, the Fund will receive a payment from or make a payment to the counterparty. Total return swap contracts are marked-to-market daily using valuations supplied by independent sources and the change in value, if any, is recorded as unrealized appreciation or depreciation in the Statement of Assets and Liabilities. Payments received or made are recorded as realized gains or losses in the Statement of Operations. Total return swap contracts are subject to counterparty risk and unanticipated movements in value of exchange rates, interest rates, securities or the index. Open total return swap contracts at October 31, 2015 are listed at the end of the Schedule of Investments. The average value of swap contracts open during the year ended October 31, 2015 was $(509,176). 2. Management Agreement PIM, a wholly owned indirect subsidiary of UniCredit, manages the Fund's portfolio. Management fees are calculated daily at an annual rate of 0.70% of the average daily net assets of the Fund, excluding assets invested in the Subsidiary and on which the Subsidiary pays a management fee. The Subsidiary has entered into a separate management contract with PIM, pursuant to which PIM manages the assets of the Subsidiary. As compensation for its management services to the Subsidiary and expenses incurred with respect to the Subsidiary, the Subsidiary pays PIM a fee at the annual rate of 0.70% of the Subsidiary's average daily net assets. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 53 PIM has contractually agreed to limit ordinary operating expenses to the extent required to reduce Fund expenses to 1.20% and 0.90% of the average daily net assets attributable to Class A and Class Y shares, respectively. These expense limitations are in effect through March 1, 2017. Fees waived and expenses reimbursed during the year ended October 31, 2015 are reflected on the Statement of Operations. Fees and expenses of other investment companies in which the Fund may invest are not included in the expense limitations noted above. There can be no assurance that PIM will extend the expense limitation agreement for a class of shares beyond the date referred to above. In addition, under the management and administration agreements, certain other services and costs, including accounting, regulatory reporting and insurance premiums, are paid by the Fund as administrative reimbursements. Included in "Due to affiliates" reflected on the Statement of Assets and Liabilities is $61,588 in management fees, administrative costs and certain other reimbursements payable to PIM at October 31, 2015. 3. Transfer Agent Pioneer Investment Management Shareholder Services, Inc. (PIMSS), a wholly owned indirect subsidiary of UniCredit, provided substantially all transfer agent and shareowner services to the Fund at negotiated rates. In addition, the Fund reimbursed PIMSS for out-of-pocket expenses incurred by PIMSS related to shareholder communications activities such as proxy and statement mailings, outgoing phone calls and omnibus relationship contracts. For the year ended October 31, 2015, such out-of-pocket expenses by class of shares were as follows: -------------------------------------------------------------------------------- Shareholder Communications: -------------------------------------------------------------------------------- Class A $178,762 Class C 215,339 Class R 185 Class Y 431,116 Class Z 231 -------------------------------------------------------------------------------- Total $825,633 ================================================================================ Included in "Due to affiliates" reflected on the Statement of Assets and Liabilities is $161,520 in transfer agent fees and out-of-pocket reimbursements payable to PIMSS at October 31, 2015. 4. Distribution Plan The Fund has adopted a Distribution Plan pursuant to Rule 12b-1 of the Investment Company Act of 1940 with respect to its Class A, Class C and Class R shares. Pursuant to the Plan, the Fund pays PFD 0.25% of the average daily net assets attributable to Class A shares as compensation for personal services and/or account maintenance services or distribution services with 54 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 regard to Class A shares. Pursuant to the Plan, the Fund also pays PFD 1.00% of the average daily net assets attributable to Class C shares. The fee for Class C shares consists of a 0.25% service fee and a 0.75% distribution fee paid as compensation for personal services and/or account maintenance services or distribution services with regard to Class C shares. Included in "Due to affiliates" reflected on the Statement of Assets and Liabilities is $22,342 in distribution fees payable to PFD at October 31, 2015. The Fund also has adopted a separate service plan for Class R shares (Service Plan). The Service Plan authorizes the Fund to pay securities dealers, plan administrators or other service organizations that agree to provide certain services to retirement plans or plan participants holding shares of the Fund a service fee of up to 0.25% of the Fund's average daily net assets attributable to Class R shares held by such plans. In addition, redemptions of each class of shares (except Class R and Class Y shares) may be subject to a contingent deferred sales charge (CDSC). A CDSC of 1.00% may be imposed on redemptions of certain net asset value purchases of Class A shares within 12 months of purchase. Redemptions of Class C shares within 12 months of purchase are subject to a CDSC of 1.00%, based on the lower of cost or market value of shares being redeemed. Shares purchased as part of an exchange remain subject to any CDSC that applied to the original purchase of those shares. There is no CDSC for Class R or Class Y shares. Proceeds from the CDSCs are paid to PFD. For the year ended October 31, 2015, CDSCs in the amount of $45,729 were paid to PFD. 5. Forward Foreign Currency Contracts At October 31, 2015, the Fund had entered into various forward foreign currency contracts that obligate the Fund to deliver or take delivery of currencies at specified future maturity dates. Alternatively, prior to the settlement date of a forward foreign currency contract, the Fund may close out such contract by entering into an offsetting contract. The average value of forward foreign currency contracts open during the year ended October 31, 2015 was $(5,480,226). There were no open forward foreign currency contracts as of October 31, 2015. 6. Expense Offset Arrangements The Fund entered into certain expense offset arrangements with PIMSS which may result in a reduction in the Fund's total expenses due to interest earned on cash held by PIMSS. For the year ended October 31, 2015, the Fund's expenses were not reduced under such arrangements. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 55 7. Line of Credit Facility The Fund, along with certain other funds in the Pioneer Family of Funds (the Funds), participates in a committed, unsecured revolving line of credit facility. Borrowings are used solely for temporary or emergency purposes. The Fund may borrow up to the lesser of the amount available under the facility or the limits set for borrowing by the Fund's prospectus and the 1940 Act. The credit facility in effect until June 9, 2015 is in the amount of $215 million. As of June 9, 2015, the facility was in the amount of $240 million. Under such facility, depending on the type of loan, interest on borrowings is payable at the London Interbank Offered Rate (LIBOR) plus 0.85% on an annualized basis, or the alternate base rate, which is the greater of (a) the facility's administrative agent's daily announced prime rate on the borrowing date, (b) 2% plus the federal funds rate on the borrowing date and (c) 2% plus the overnight eurodollar rate on the borrowing date. The Funds pay an annual commitment fee to participate in the credit facility. The commitment fee is allocated among participating Funds based on an allocation schedule set forth in the credit agreement. For the year ended October 31, 2015, the Fund had no borrowings under the credit facility. 8. Assets and Liabilities Offsetting The Fund has entered into an International Swaps and Derivatives Association, Inc. Master Agreement ("ISDA Master Agreement") or similar agreement with substantially all its derivative counterparties. An ISDA Master Agreement is a bilateral agreement between the Fund and a counterparty that governs the trading of certain OTC derivatives and typically contains, among other things, close-out and set-off provisions which apply upon the occurrence of event of a default and/or termination event as defined under the relevant ISDA Master Agreement. The ISDA Master Agreement may also give a party the right to terminate all transactions traded under such agreement if, among other things, there is deterioration in the credit quality of the other party. Upon an event of default or a termination of the ISDA Master Agreement, the non-defaulting party has the right to close out all transactions under such agreement and to net amounts owed under each transaction to determine one net amount payable by one party to the other. The right to close out and net payments across all transactions under the ISDA Master Agreement could result in a reduction of the Fund's credit risk to its counterparty equal to any amounts payable by the Fund under the applicable transactions, if any. However, the Fund's right to setoff may be restricted or prohibited by the bankruptcy or insolvency laws of the particular jurisdiction to which a specific ISDA counterparty is subject. 56 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 The collateral requirements for derivatives transactions under an ISDA Master Agreement are governed by a credit support annex to the ISDA Master Agreement. Collateral requirements are generally determined at the close of business each day and are typically based on changes in market values for each transaction under an ISDA Master Agreement and netted into one amount for such agreement. Generally, the amount of collateral due from or to a counterparty is subject to threshold (a "minimum transfer amount") before a transfer is required, which may vary by counterparty. Collateral pledged for the benefit of the Fund and/or counterparty is held in segregated accounts by the Fund's custodian and cannot be sold, re-pledged, assigned or otherwise used while pledged. Cash that has been segregated to cover the Fund's collateral obligations, if any, will be reported separately in the Statement of Assets and Liabilities as "Futures collateral", "Swap Collateral " or "Deposit with broker." Securities pledged by the Fund as collateral, if any, are identified as such in the Schedule of Investments. Financial instruments subject to an enforceable master netting agreement such as an ISDA Master Agreement have been offset on the Statement of Assets and Liabilities. The following charts show gross assets and liabilities of the Fund as of October 31, 2015. ---------------------------------------------------------------------------------------------------------- Derivative Assets Derivatives Non-Cash Cash Amount Subject to Master Available for Collateral Collateral Derivative Counterparty Netting Agreement Offset Received(a) Received(a) Assets(b) ---------------------------------------------------------------------------------------------------------- Societe Generale SA $495,991 $ -- $ -- $ -- $495,991 Citibank N.A. -- -- -- -- -- ---------------------------------------------------------------------------------------------------------- Total $495,991 $ -- $ -- $ -- $495,991 ========================================================================================================== ---------------------------------------------------------------------------------------------------------- Derivative Liabilities Derivatives Non-Cash Cash Amount Subject to Master Available for Collateral Collateral Derivative Counterparty Netting Agreement Offset Pledged(a) Pledged(a) Liabilities(c) ---------------------------------------------------------------------------------------------------------- Societe Generale SA $ -- $ -- $ -- $ -- $ -- Citibank N.A. 13,337 -- -- (2,582) 10,755 ---------------------------------------------------------------------------------------------------------- Total $ 13,337 $ -- $ -- $ (2,582) $ 10,755 ========================================================================================================== (a) The amount presented here may be less than the total amount of collateral received/pledged as the net amount of derivative assets and liabilities cannot be less than $0. (b) Represents the net amount due from the counterparty in the event of default. (c) Represents the net amount payable to the counterparty in the event of default. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 57 9. Additional Disclosures about Derivative Instruments and Hedging Activities: The Fund's use of derivatives subjects it to the following risks: Interest rate risk relates to the fluctuations in the value of interest-bearing securities due to changes in the prevailing levels of market interest rates. Credit risk relates to the ability of the issuer of a financial instrument to make further principal or interest payments on an obligation or commitment that it has to the Fund. Foreign exchange rate risk relates to fluctuations in the value of an asset or liability due to changes in currency exchange rates. Equity risk relates to the fluctuations in the value of financial instruments as a result of changes in market prices (other than those arising from interest rate risk or foreign exchange risk), whether caused by factors specific to an individual investment, its issuer, or all factors affecting all instruments traded in a market or market segment. Commodity risk relates to the risk that the value of a commodity or commodity index will fluctuate based on increases or decreases in the commodities market and factors specific to a particular industry or commodity. The fair value of open derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) by risk exposure at October 31, 2015 was as follows: ------------------------------------------------------------------------------------------- Statement of Assets and Liabilities Interest Credit Foreign Equity Commodity Assets Rate Risk Risk Exchange Rate Risk Risk ------------------------------------------------------------------------------------------- Net unrealized appreciation on swap contracts $ -- $ -- $ -- $ 482,654 $ -- ------------------------------------------------------------------------------------------- Total Value $ -- $ -- $ -- $ 482,654 $ -- =========================================================================================== Liabilities Net unrealized depreciation on futures contracts $(282,824) $-- $591,063 $(2,611,189) $1,132,295 ------------------------------------------------------------------------------------------- Total Value $(282,824) $-- $591,063 $(2,611,189) $1,132,295 =========================================================================================== The effect of derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) on the Statement of Operations by risk exposure at October 31, 2015 was as follows: 58 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 -------------------------------------------------------------------------------------------- Statement of Operations Foreign Interest Credit Exchange Equity Commodity Rate Risk Risk Rate Risk Risk Risk -------------------------------------------------------------------------------------------- Net realized gain (loss) on Swap contracts $ -- $ -- $ -- $ (4,193,541) $ -- Futures contracts 5,235,386 -- 9,655,658 (11,395,272) (3,774,837) Written options 1,763,120 -- (1,565,517) 23,468,368 (2,521,424) Forward foreign currency contracts -- -- (603,660) -- -- -------------------------------------------------------------------------------------------- Total Value $6,998,506 $ -- $ 7,486,481 $ 7,879,555 $(6,296,261) ============================================================================================ -------------------------------------------------------------------------------------------- Foreign Interest Credit Exchange Equity Commodity Rate Risk Risk Rate Risk Risk Risk -------------------------------------------------------------------------------------------- Change in net unrealized appreciation (depreciation) on Swap contracts $ -- $ -- $ -- $ 482,654 $ -- Futures contracts (1,306,699) -- (551,258) (2,143,760) 1,258,695 Written options -- -- -- (1,621,508) -- Forward foreign currency contracts -- -- 132,430 -- -- -------------------------------------------------------------------------------------------- Total Value $(1,306,699) $ -- $(418,828) $(3,282,614) $ 1,258,695 ============================================================================================ 11. Conversion of Class Z Shares As of the close of business on August 7, 2015 (the "Conversion Date"), all outstanding Class Z shares of the Fund were converted to Class Y shares. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 59 Report of Independent Registered Public Accounting Firm To the Board of Trustees of Pioneer Series Trust VI and the Shareowners of Pioneer Flexible Opportunities Fund (formerly, Pioneer Multi-Asset Real Return Fund): -------------------------------------------------------------------------------- We have audited the accompanying consolidated statement of assets and liabilities, including the consolidated schedule of investments, of Pioneer Flexible Opportunities Fund (formerly, Pioneer Multi-Asset Real Return Fund) (one of the portfolio's constituting Pioneer Series Trust VI), as of October 31, 2015, and the related consolidated statement of operations for the year then ended and the consolidated statements of changes in net assets and the consolidated financial highlights for each of the two years in the period then ended. These financial statements and financial highlights are the responsibility of the Fund's management. Our responsibility is to express an opinion on these financial statements and financial highlights based on our audits. The consolidated financial highlights for the years ended October 31, 2013, 2012, and 2011 were audited by other auditors. Those auditors expressed an unqualified opinion on those consolidated financial statements and consolidated financial highlights in their report dated December 23, 2013. We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements and financial highlights are free of material misstatement. The Fund is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. Our audits included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Fund's internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. Our procedures included confirmation of securities owned as of October 31, 2015, by correspondence with the custodian and brokers; where replies were not received from brokers, we performed other auditing procedures. We believe that our audits provide a reasonable basis for our opinion. In our opinion, the consolidated financial statements and consolidated financial highlights referred to above present fairly, in all material respects, the financial position of Pioneer Flexible Opportunities Fund (formerly, Pioneer Multi-Asset Real Return Fund) as of October 31, 2015, the results of its operations for the year then ended, and the changes in its net assets and the financial highlights for each of the two years in the period then ended, in conformity with accounting principles generally accepted in the United States of America. /s/ Deloitte & Touche LLP Boston, Massachusetts December 23, 2015 60 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 ADDITIONAL INFORMATION (unaudited) PIM, the Fund's investment adviser, is currently an indirect, wholly owned subsidiary of UniCredit. On November 11, 2015, UniCredit announced that it signed a binding master agreement with Banco Santander and affiliates of Warburg Pincus and General Atlantic (the "Private Equity Firms") with respect to Pioneer Investments ("Pioneer") and Santander Asset Management ("SAM") (the "Transaction"). The Transaction, as previously announced by UniCredit, will establish a holding company, with the name Pioneer Investments, to be owned by UniCredit (50%) and the Private Equity Firms (50% between them). The holding company will control Pioneer's U.S. operations, including PIM. The holding company also will own 66.7% of Pioneer's and SAM's combined operations outside the U.S., while Banco Santander will own directly the remaining 33.3% stake. The closing of the Transaction is expected to happen in 2016, subject to certain regulatory and other approvals. Under the Investment Company Act of 1940, completion of the Transaction will cause the Fund's current investment advisory agreement with PIM to terminate. Accordingly, the Fund's Board of Trustees will be asked to approve a new investment advisory agreement. If approved by the Board, the Fund's new investment advisory agreement will be submitted to the shareholders of the Fund for their approval. For the year ended October 31, 2015, certain dividends paid by the Fund may be subject to a maximum tax rate of 15%, as provided for by the Jobs and Growth Tax Relief Reconciliation Act (the Act) of 2003. The Fund intends to designate up to the maximum amount of such dividends allowable under the Act, as taxed at a maximum rate of 15%. Complete information will be computed and reported in conjunction with your 2014 form 1099-DIV. The qualifying percentage of the Fund's ordinary income dividends for the purpose of the corporate dividends received deduction was 31.12%. The percentages of the Fund's ordinary income distributions that are exempt from nonresident alien (NRA) tax withholding resulting from qualified interest income was 6.51%. SUBSEQUENT EVENT (unaudited) Effective November 2, 2015, Boston Financial Data Service became the transfer agent to the Fund at negotiated rates. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 61 Approval of Investment Advisory Agreement and Subsidiary Management Agreement Pioneer Investment Management, Inc. (PIM) serves as the investment adviser to Pioneer Flexible Opportunities Fund (the Fund) pursuant to an investment advisory agreement between PIM and the Fund. In order for PIM to remain the investment adviser of the Fund, the Trustees of the Fund must determine annually whether to renew the investment advisory agreement for the Fund. The contract review process began in January 2015 as the Trustees of the Fund agreed on, among other things, an overall approach and timeline for the process. Contract review materials were provided to the Trustees in March 2015 and July 2015. Supplemental contract review materials were provided to the Trustees in September 2015. In addition, the Trustees reviewed and discussed the Fund's performance at regularly scheduled meetings throughout the year and took into account other information related to the Fund provided to the Trustees at regularly scheduled meetings in connection with the review of the Fund's investment advisory agreement. In March 2015, the Trustees, among other things, discussed the memorandum provided by Fund counsel that summarized the legal standards and other considerations that are relevant to the Trustees in their deliberations regarding the renewal of the investment advisory agreement, and reviewed and discussed the qualifications of the investment management teams, as well as the level of investment by the Fund's portfolio managers in the Fund. In July 2015, the Trustees, among other things, reviewed the Fund's management fee and total expense ratios, the financial statements of PIM and its parent companies, the profitability analyses provided by PIM, and possible economies of scale. The Trustees also reviewed the profitability of the institutional business of PIM and PIM's affiliate, Pioneer Institutional Asset Management, Inc. (together with PIM, "Pioneer"), as compared to that of PIM's fund management business, and considered the differences between the fees and expenses of the Fund and the fees and expenses of Pioneer's institutional accounts, as well as the different services provided by PIM to the Fund and by Pioneer to the institutional accounts. The Trustees further considered contract review materials in September 2015. At a meeting held on September 15, 2015, based on their evaluation of the information provided by PIM and third parties, the Trustees of the Fund, including the Independent Trustees voting separately, unanimously approved the renewal of the investment advisory agreement for another year. In approving the renewal of the investment advisory agreement, the Trustees considered various factors that they determined were relevant, including the factors described below. The Trustees did not identify any single factor as the controlling factor in determining to approve the renewal of the agreement. 62 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 PIM also serves as the investment adviser to Pioneer Cayman Commodity Fund, Ltd. (the Subsidiary), a wholly-owned subsidiary of the Fund organized under the laws of the Cayman Islands. The Trustees, including the independent Trustees voting separately, unanimously approved the renewal of the investment advisory agreement for the Subsidiary (the Subsidiary Management Agreement) for another year. The factors considered by the Trustees in approving the renewal of the Subsidiary Management Agreement were substantially the same as the factors described below with respect to the investment advisory agreement for the Fund. Nature, Extent and Quality of Services The Trustees considered the nature, extent and quality of the services that had been provided by PIM to the Fund, taking into account the investment objective and strategy of the Fund. The Trustees also reviewed PIM's investment approach for the Fund and its research process. The Trustees considered the resources of PIM and the personnel of PIM who provide investment management services to the Fund. They also reviewed the amount of non-Fund assets managed by the portfolio managers of the Fund. The Trustees considered the non-investment resources and personnel of PIM involved in PIM's services to the Fund, including PIM's compliance and legal resources and personnel. The Trustees noted the substantial attention and high priority given by PIM's senior management to the Pioneer fund complex. The Trustees considered that PIM supervises and monitors the performance of the Fund's service providers and provides the Fund with personnel (including Fund officers) and other resources that are necessary for the Fund's business management and operations. The Trustees also considered that, as administrator, PIM is responsible for the administration of the Fund's business and other affairs. The Trustees considered the fees paid to PIM for the provision of administration services. Based on these considerations, the Trustees concluded that the nature, extent and quality of services that had been provided by PIM to the Fund were satisfactory and consistent with the terms of the investment advisory agreement. Performance of the Fund In considering the Fund's performance, the Trustees regularly review and discuss throughout the year data prepared by PIM and information comparing the Fund's performance with the performance of its peer group of funds as classified by each of Morningstar, Inc. (Morningstar) and Lipper, and with the performance of the Fund's benchmark index. They also discuss the Fund's Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 63 performance with PIM on a regular basis. The Trustees' regular reviews and discussions were factored into the Trustees' deliberations concerning the renewal of the advisory agreement. Management Fee and Expenses The Trustees considered information showing the fees and expenses of the Fund in comparison to the management fees and expense ratios of its peer group of funds as classified by Morningstar and also to the expense ratios of a peer group of funds selected on the basis of criteria determined by the Independent Trustees for this purpose using data provided by Strategic Insight Mutual Fund Research and Consulting, LLC (Strategic Insight), an independent third party. In all quintile rankings referred to below, first quintile is most favorable to the Fund's shareowners. The Trustees considered that the Fund's management fee for the most recent fiscal year was in the first quintile relative to the management fees paid by other funds in its Morningstar peer group for the comparable period. The Trustees noted that although assets invested by the Fund in the Subsidiary are excluded from the calculation of the Fund's management fee, the Fund indirectly pays a management fee with respect to assets invested in the Subsidiary because the Subsidiary pays a management fee pursuant to the Subsidiary Management Agreement. The Trustees noted that the Subsidiary pays PIM a management fee at the same rate that the Fund pays PIM. The Trustees considered that the expense ratio of the Fund's Class A shares for the most recent fiscal year was in the second quintile relative to its Morningstar peer group and in the second quintile relative its Strategic Insight peer group, in each case for the comparable period. The Trustees considered that the expense ratio of the Fund's Class Y shares for the most recent fiscal year was in the first quintile relative to its Morningstar peer group and in the second quintile relative its Strategic Insight peer group, in each case for the comparable period. The Trustees noted that PIM was waiving fees and/or reimbursing expenses in order to limit the ordinary operating expenses of the Fund. The Trustees considered the impact of transfer agency, sub-transfer agency, and other non-management fee expenses on the expense ratios of the Fund. The Trustees noted that they separately review the Fund's transfer agency, sub-transfer agency and intermediary arrangements. The Trustees reviewed management fees charged by Pioneer to institutional and other clients, including publicly offered European funds sponsored by affiliates of Pioneer, unaffiliated U.S. registered investment companies (in a sub-advisory capacity), and unaffiliated foreign and domestic separate accounts. The Trustees also considered PIM's costs in providing services to the Fund and Pioneer's costs in providing services to the other clients and 64 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 considered the differences in management fees and profit margins for Fund and non-Fund services. In evaluating the fees associated with Pioneer's client accounts, the Trustees took into account the respective demands, resources and complexity associated with the Fund and client accounts. The Trustees noted that, in some instances, the fee rates for those clients were lower than the management fee for the Fund and considered that, under the investment advisory agreement with the Fund, PIM performs additional services for the Fund that it does not provide to those other clients or services that are broader in scope, including oversight of the Fund's other service providers and activities related to compliance and the extensive regulatory and tax regimes to which the Fund is subject. The Trustees also considered the different entrepreneurial risks associated with PIM's management of the Fund and Pioneer's management of the other client accounts. The Trustees concluded that the management fee payable by the Fund to PIM was reasonable in relation to the nature and quality of the services provided by PIM to the Fund. Profitability The Trustees considered information provided by PIM regarding the profitability of PIM with respect to the advisory services provided by PIM to the Fund, including the methodology used by PIM in allocating certain of its costs to the management of the Fund. The Trustees also considered PIM's profit margin in connection with the overall operation of the Fund. They further reviewed the financial results realized by PIM and its affiliates from non-fund businesses. The Trustees considered PIM's profit margins with respect to the Fund in comparison to the limited industry data available and noted that the profitability of any adviser was affected by numerous factors, including its organizational structure and method for allocating expenses. The Trustees concluded that PIM's profitability with respect to the management of the Fund was not unreasonable. Economies of Scale The Trustees considered PIM's views relating to economies of scale in connection with the Pioneer Funds as fund assets grow and the extent to which any such economies of scale are shared with funds and fund shareholders. The Trustees recognize that economies of scale are difficult to identify and quantify, and that, among other factors that may be relevant, are the following: fee levels, expense subsidization, investment by PIM in research and analytical capabilities and PIM's commitment and resource allocation to the Fund. The Trustees noted that profitability also may be an indicator of the Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 65 availability of any economies of scale, although profitability may vary for other reasons including reductions in expenses. The Trustees concluded that economies of scale, if any, were being appropriately shared with the Funds. Other Benefits The Trustees considered the other benefits to PIM from its relationship with the Fund. The Trustees considered the character and amount of fees paid by the Fund, other than under the investment advisory agreement, for services provided by PIM and its affiliates. The Trustees further considered the revenues and profitability of PIM's businesses other than the fund business. Pioneer is the principal U.S. asset management business of Pioneer Global Asset Management, the worldwide asset management business of UniCredit Group, which manages over $150 billion in assets (including the Funds). Pioneer and the Funds receive reciprocal intangible benefits from the relationship, including mutual brand recognition and, for the Funds, direct and indirect access to the resources of a large global asset manager. The Trustees concluded that any such benefits received by Pioneer as a result of its relationship with the Funds were reasonable and their consideration of the advisory agreement between the Fund and PIM and the fees thereunder were unaffected by Pioneer's possible receipt of any such intangible benefits. Conclusion After consideration of the factors described above as well as other factors, the Trustees, including all of the Independent Trustees, concluded that each of the investment advisory agreement between PIM and the Fund and the Subsidiary Management Agreement, including, in each case, the fees payable thereunder, was fair and reasonable and voted to approve the proposed renewal of each of the investment advisory agreement for the Fund and the Subsidiary Management Agreement. 66 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Trustees, Officers and Service Providers Investment Adviser Pioneer Investment Management, Inc. Custodian and Sub-Administrator Brown Brothers Harriman & Co. Independent Registered Public Accounting Firm Deloitte & Touche LLP Principal Underwriter Pioneer Funds Distributor, Inc. Legal Counsel Morgan, Lewis & Bockius LLP Shareowner Services and Transfer Agent Boston Financial Data Services, Inc. Proxy Voting Policies and Procedures of the Fund are available without charge, upon request, by calling our toll free number (1-800-225-6292). Information regarding how the Fund voted proxies relating to portfolio securities during the most recent 12-month period ended June 30 is publicly available to shareowners at us.pioneerinvestments.com. This information is also available on the Securities and Exchange Commission's web site at www.sec.gov. Trustees and Officers The Fund's Trustees and officers are listed below, together with their principal occupations during at least the past five years. Trustees who are interested persons of the Fund within the meaning of the 1940 Act are referred to as Interested Trustees. Trustees who are not interested persons of the Fund are referred to as Independent Trustees. Each of the Trustees serves as a trustee of each of the 50 U.S. registered investment portfolios for which Pioneer serves as investment adviser (the "Pioneer Funds"). The address for all Trustees and all officers of the Fund is 60 State Street, Boston, Massachusetts 02109. The Statement of Additional Information of the Fund includes additional information about the Trustees and is available, without charge, upon request, by calling 1-800-225-6292. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 67 Independent Trustees ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Thomas J. Perna (65) Trustee since 2010. Private investor (2004 - 2008 and 2013 - present); Director, Broadridge Chairman of the Board Serves until a Chairman (2008 - 2013) and Chief Executive Officer Financial Solutions, Inc. and Trustee successor trustee (2008 - 2012), Quadriserv, Inc. (technology (investor communications and is elected or products for securities lending industry); and securities processing earlier retirement Senior Executive Vice President, The Bank of New provider for financial or removal. York (financial and securities services) (1986 - services industry) (2009 - 2004) present); Director, Quadriserv, Inc. (2005 - 2013); and Commissioner, New Jersey State Civil Service Commission (2011 - present) ------------------------------------------------------------------------------------------------------------------------------------ David R. Bock (71) Trustee since 2010. Managing Partner, Federal City Capital Advisors Director of New York Mortgage Trustee Serves until a (corporate advisory services company) (1997 - 2004 Trust (publicly-traded successor trustee and 2008 - present); Interim Chief Executive mortgage REIT) (2004 - 2009, is elected or Officer, Oxford Analytica, Inc. (privately-held 2012 - present); Director of earlier retirement research and consulting company) (2010); Executive The Swiss Helvetia Fund, Inc. or removal. Vice President and Chief Financial Officer, (closed-end fund) (2010 - I-trax, Inc. (publicly traded health care services present); Director of Oxford company) (2004 - 2007); and Executive Vice Analytica, Inc. (2008 - President and Chief Financial Officer, Pedestal present); and Director of Inc. (internet-based mortgage trading company) Enterprise Community (2000 - 2002); Private consultant (1995-1997), Investment, Inc. Managing Director, Lehman Brothers (investment (privately-held affordable banking firm) (1992-1995); and Executive, The housing finance company) World Bank (1979-1992) (1985 - 2010) ------------------------------------------------------------------------------------------------------------------------------------ Benjamin M. Friedman (71) Trustee since 2010. William Joseph Maier Professor of Political Trustee, Mellon Institutional Trustee Serves until a Economy, Harvard University (1972 - present) Funds Investment Trust and successor trustee Mellon Institutional Funds is elected or Master Portfolio (oversaw 17 earlier retirement portfolios in fund complex) or removal. (1989-2008) ------------------------------------------------------------------------------------------------------------------------------------ 68 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Margaret B.W. Graham (68) Trustee since 2010. Founding Director, Vice President and Corporate None Trustee Serves until a Secretary, The Winthrop Group, Inc. (consulting successor trustee firm) (1982 - present); Desautels Faculty of is elected or Management, McGill University (1999 - present); earlier retirement and Manager of Research Operations and or removal. Organizational Learning, Xerox PARC, Xerox's advance research center (1990-1994) ------------------------------------------------------------------------------------------------------------------------------------ Marguerite A. Piret (67) Trustee since 2010. President and Chief Executive Officer, Newbury, Director of New America High Trustee Serves until a Piret & Company, Inc. (investment banking firm) Income Fund, Inc. (closed-end successor trustee (1981 - present) investment company) (2004 - is elected or present); and Member, Board earlier retirement of Governors, Investment or removal. Company Institute (2000 - 2006) ------------------------------------------------------------------------------------------------------------------------------------ Fred J. Ricciardi (68) Trustee since 2014. Consultant (investment company services) (2012 - None Trustee Serves until a present); Executive Vice President, BNY Mellon successor trustee (financial and investment company services) (1969 is elected or - 2012); Director, BNY International Financing earlier retirement Corp. (financial services) (2002 - 2012); and or removal. Director, Mellon Overseas Investment Corp. (financial services) (2009 - 2012) ------------------------------------------------------------------------------------------------------------------------------------ Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 69 Interested Trustee ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Kenneth J. Taubes (57)* Trustee since 2014. Director and Executive Vice President (since 2008) None Trustee Serves until a and Chief Investment Officer, U.S. (since 2010) of successor trustee PIM-USA; Executive Vice President of Pioneer is elected or (since 2008); Executive Vice President of Pioneer earlier retirement Institutional Asset Management, Inc. (since 2009); or removal. and Portfolio Manager of Pioneer (since 1999) ------------------------------------------------------------------------------------------------------------------------------------ * Mr. Taubes is an Interested Trustee because he is an officer of the Fund's investment adviser and certain of its affiliates. 70 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 Advisory Trustee ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Lorraine H. Monchak (59)** Advisory Trustee Chief Investment Officer, 1199 SEIU Funds Trustee of Pioneer Advisory Trustee since 2014. (healthcare workers union pension funds) (2001 - closed-end investment present); Vice President - International companies (5 portfolios) Investments Group, American International Group, (Sept. 2015 - present) Inc. (insurance company) (1993 - 2001); Vice President Corporate Finance and Treasury Group, Citibank, N.A.(1980 - 1986 and 1990 - 1993); Vice President - Asset/Liability Management Group, Federal Farm Funding Corporation (government-sponsored issuer of debt securities) (1988 - 1990); Mortgage Strategies Group, Shearson Lehman Hutton, Inc. (investment bank) (1987 - 1988); and Mortgage Strategies Group, Drexel Burnham Lambert, Ltd. (investment bank) (1986 - 1987) ------------------------------------------------------------------------------------------------------------------------------------ ** Ms. Monchak is a non-voting advisory trustee. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 71 Fund Officers ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Lisa M. Jones (53) Since 2014. Serves Chair, Director, CEO and President of Pioneer Trustee of Pioneer President and Chief at the discretion of Investment Management-USA (since September 2014); closed-end investment Executive Officer the Board. Chair, Director, CEO and President of Pioneer companies (5 portfolios) Investment Management, Inc. (since September (Sept. 2015 - present) 2014); Chair, Director, CEO and President of Pioneer Funds Distributor, Inc. (since September 2014); Chair, Director, CEO and President of Pioneer Institutional Asset Management, Inc. (since September 2014); and Chair, Director, and CEO of Pioneer Investment Management Shareholder Services, Inc. (since September 2014); Managing Director, Morgan Stanley Investment Management (2010 - 2013); and Director of Institutional Business, CEO of International, Eaton Vance Management (2005 - 2010) ------------------------------------------------------------------------------------------------------------------------------------ Christopher J. Kelley (50) Since 2010. Serves Vice President and Associate General Counsel of None Secretary and Chief at the discretion of Pioneer since January 2008; Secretary and Chief Legal Officer the Board. Legal Officer of all of the Pioneer Funds since June 2010; Assistant Secretary of all of the Pioneer Funds from September 2003 to May 2010; and Vice President and Senior Counsel of Pioneer from July 2002 to December 2007 ------------------------------------------------------------------------------------------------------------------------------------ Carol B. Hannigan (54) Since 2010. Serves Fund Governance Director of Pioneer since December None Assistant Secretary at the discretion of 2006 and Assistant Secretary of all the Pioneer the Board. Funds since June 2010; Manager - Fund Governance of Pioneer from December 2003 to November 2006; and Senior Paralegal of Pioneer from January 2000 to November 2003 ------------------------------------------------------------------------------------------------------------------------------------ Thomas Reyes (52) Since 2010. Serves Senior Counsel of Pioneer since May 2013 and None Assistant Secretary at the discretion of Assistant Secretary of all the Pioneer Funds since the Board. June 2010; and Counsel of Pioneer from June 2007 to May 2013 ------------------------------------------------------------------------------------------------------------------------------------ Mark E. Bradley (55) Since 2010. Serves Vice President - Fund Treasury of Pioneer; None Treasurer and Chief at the discretion of Treasurer of all of the Pioneer Funds since March Financial and the Board. 2008; Deputy Treasurer of Pioneer from March 2004 Accounting Officer to February 2008; and Assistant Treasurer of all of the Pioneer Funds from March 2004 to February 2008 ------------------------------------------------------------------------------------------------------------------------------------ 72 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 ------------------------------------------------------------------------------------------------------------------------------------ Name, Age and Term of Office and Other Directorships Position Held With the Fund Length of Service Principal Occupation Held by Trustee ------------------------------------------------------------------------------------------------------------------------------------ Luis I. Presutti (50) Since 2010. Serves Director - Fund Treasury of Pioneer; and Assistant None Assistant Treasurer at the discretion Treasurer of all of the Pioneer Funds of the Board. ------------------------------------------------------------------------------------------------------------------------------------ Gary Sullivan (57) Since 2010. Serves Fund Accounting Manager - Fund Treasury of None Assistant Treasurer at the discretion Pioneer; and Assistant Treasurer of all of the of the Board. Pioneer Funds ------------------------------------------------------------------------------------------------------------------------------------ David F. Johnson (35) Since 2010. Serves Fund Administration Manager - Fund Treasury of None Assistant Treasurer at the discretion Pioneer since November 2008; Assistant Treasurer of the Board. of all of the Pioneer Funds since January 2009; and Client Service Manager - Institutional Investor Services at State Street Bank from March 2003 to March 2007 ------------------------------------------------------------------------------------------------------------------------------------ Jean M. Bradley (63) Since 2010. Serves Chief Compliance Officer of Pioneer and of all the None Chief Compliance Officer at the discretion Pioneer Funds since March 2010; Chief Compliance of the Board. Officer of Pioneer Institutional Asset Management, Inc. since January 2012; Chief Compliance Officer of Vanderbilt Capital Advisors, LLC since July 2012: Director of Adviser and Portfolio Compliance at Pioneer since October 2005; and Senior Compliance Officer for Columbia Management Advisers, Inc. from October 2003 to October 2005 ------------------------------------------------------------------------------------------------------------------------------------ Kelly O'Donnell (44) Since 2010. Serves Director - Transfer Agency Compliance of Pioneer None Anti-Money Laundering at the discretion and Anti-Money Laundering Officer of all the Officer of the Board. Pioneer Funds since 2006 ------------------------------------------------------------------------------------------------------------------------------------ Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 73 This page for your notes. 74 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 This page for your notes. Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 75 This page for your notes. 76 Pioneer Flexible Opportunities Fund | Annual Report | 10/31/15 How to Contact Pioneer We are pleased to offer a variety of convenient ways for you to contact us for assistance or information. Call us for: -------------------------------------------------------------------------------- Account Information, including existing accounts, new accounts, prospectuses, applications and service forms 1-800-225-6292 FactFone(SM) for automated fund yields, prices, account information and transactions 1-800-225-4321 Retirement plans information 1-800-622-0176 Write to us: -------------------------------------------------------------------------------- Pioneer Funds P.O. Box 55014 Boston, Massachusetts 02205-5014 Our toll-free fax 1-800-225-4240 Our internet e-mail address ask.pioneer@pioneerinvestments.com (for general questions about Pioneer only) Visit our web site: us.pioneerinvestments.com This report must be preceded or accompanied by a prospectus. The Fund files a complete schedule of investments with the Securities and Exchange Commission for the first and third quarters for each fiscal year on Form N-Q. Shareholders may view the filed Form N-Q by visiting the Commission's web site at www.sec.gov. The filed form may also be viewed and copied at the Commission's Public Reference Room in Washington, DC. Information regarding the operations of the Public Reference Room may be obtained by calling 1-800-SEC-0330. [LOGO] PIONEER Investments(R) Pioneer Investment Management, Inc. 60 State Street Boston, MA 02109 us.pioneerinvestments.com Securities offered through Pioneer Funds Distributor, Inc. 60 State Street, Boston, MA 02109 Underwriter of Pioneer Mutual Funds, Member SIPC (C) 2015 Pioneer Investments 24440-05-1215 ITEM 2. CODE OF ETHICS. (a) Disclose whether, as of the end of the period covered by the report, the registrant has adopted a code of ethics that applies to the registrant's principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, regardless of whether these individuals are employed by the registrant or a third party. If the registrant has not adopted such a code of ethics, explain why it has not done so. The registrant has adopted, as of the end of the period covered by this report, a code of ethics that applies to the registrant's principal executive officer, principal financial officer, principal accounting officer and controller. (b) For purposes of this Item, the term "code of ethics" means written standards that are reasonably designed to deter wrongdoing and to promote: (1) Honest and ethical conduct, including the ethical handling of actual or apparent conflicts of interest between personal and professional relationships; (2) Full, fair, accurate, timely, and understandable disclosure in reports and documents that a registrant files with, or submits to, the Commission and in other public communications made by the registrant; (3) Compliance with applicable governmental laws, rules, and regulations; (4) The prompt internal reporting of violations of the code to an appropriate person or persons identified in the code; and (5) Accountability for adherence to the code. (c) The registrant must briefly describe the nature of any amendment, during the period covered by the report, to a provision of its code of ethics that applies to the registrant's principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, regardless of whether these individuals are employed by the registrant or a third party, and that relates to any element of the code of ethics definition enumerated in paragraph (b) of this Item. The registrant must file a copy of any such amendment as an exhibit pursuant to Item 10(a), unless the registrant has elected to satisfy paragraph (f) of this Item by posting its code of ethics on its website pursuant to paragraph (f)(2) of this Item, or by undertaking to provide its code of ethics to any person without charge, upon request, pursuant to paragraph (f)(3) of this Item. The registrant has made no amendments to the code of ethics during the period covered by this report. (d) If the registrant has, during the period covered by the report, granted a waiver, including an implicit waiver, from a provision of the code of ethics to the registrant's principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, regardless of whether these individuals are employed by the registrant or a third party, that relates to one or more of the items set forth in paragraph (b) of this Item, the registrant must briefly describe the nature of the waiver, the name of the person to whom the waiver was granted, and the date of the waiver. Not applicable. (e) If the registrant intends to satisfy the disclosure requirement under paragraph (c) or (d) of this Item regarding an amendment to, or a waiver from, a provision of its code of ethics that applies to the registrant's principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions and that relates to any element of the code of ethics definition enumerated in paragraph (b) of this Item by posting such information on its Internet website, disclose the registrant's Internet address and such intention. Not applicable. (f) The registrant must: (1) File with the Commission, pursuant to Item 12(a)(1), a copy of its code of ethics that applies to the registrant's principal executive officer,principal financial officer, principal accounting officer or controller, or persons performing similar functions, as an exhibit to its annual report on this Form N-CSR (see attachment); (2) Post the text of such code of ethics on its Internet website and disclose, in its most recent report on this Form N-CSR, its Internet address and the fact that it has posted such code of ethics on its Internet website; or (3) Undertake in its most recent report on this Form N-CSR to provide to any person without charge, upon request, a copy of such code of ethics and explain the manner in which such request may be made. 	See Item 10(2) ITEM 3. AUDIT COMMITTEE FINANCIAL EXPERT. (a) (1) Disclose that the registrant's board of trustees has determined that the registrant either: (i) Has at least one audit committee financial expert serving on its audit committee; or (ii) Does not have an audit committee financial expert serving on its audit committee. The registrant's Board of Trustees has determined that the registrant has at least one audit committee financial expert. (2) If the registrant provides the disclosure required by paragraph (a)(1)(i) of this Item, it must disclose the name of the audit committee financial expert and whether that person is "independent." In order to be considered "independent" for purposes of this Item, a member of an audit committee may not, other than in his or her capacity as a member of the audit committee, the board of trustees, or any other board committee: (i) Accept directly or indirectly any consulting, advisory, or other compensatory fee from the issuer; or (ii) Be an "interested person" of the investment company as defined in Section 2(a)(19) of the Act (15 U.S.C. 80a-2(a)(19)). Ms. Marguerite A. Piret, an independent trustee, is such an audit committee financial expert. (3) If the registrant provides the disclosure required by paragraph (a)(1) (ii) of this Item, it must explain why it does not have an audit committee financial expert. Not applicable. ITEM 4. PRINCIPAL ACCOUNTANT FEES AND SERVICES. (a) Disclose, under the caption AUDIT FEES, the aggregate fees billed for each of the last two fiscal years for professional services rendered by the principal accountant for the audit of the registrant's annual financial statements or services that are normally provided by the accountant in connection with statutory and regulatory filings or engagements for those fiscal years. The audit fees for the Trust were $116,877 payable to Deloitte & Touche LLP for the year ended October 31, 2015 and $106,469 for the year ended October 31, 2014. (b) Disclose, under the caption AUDIT-RELATED FEES, the aggregate fees billed in each of the last two fiscal years for assurance and related services by the principal accountant that are reasonably related to the performance of the audit of the registrant's financial statements and are not reported under paragraph (a) of this Item. Registrants shall describe the nature of the services comprising the fees disclosed under this category. There were no audit-related services in 2015 or 2014. (c) Disclose, under the caption TAX FEES, the aggregate fees billed in each of the last two fiscal years for professional services rendered by the principal accountant for tax compliance, tax advice, and tax planning. Registrants shall describe the nature of the services comprising the fees disclosed under this category. The tax fees for the Trust were $17,500 payable to Deloitte & Touche LLP for the year ended October 31, 2015 and $17,500 for the year ended October 31, 2014. (d) Disclose, under the caption ALL OTHER FEES, the aggregate fees billed in each of the last two fiscal years for products and services provided by the principal accountant, other than the services reported in paragraphs (a) through (c) of this Item. Registrants shall describe the nature of the services comprising the fees disclosed under this category. There were no other fees in 2015 or 2014. (e) (1) Disclose the audit committee's pre-approval policies and procedures described in paragraph (c)(7) of Rule 2-01 of Regulation S-X. PIONEER FUNDS APPROVAL OF AUDIT, AUDIT-RELATED, TAX AND OTHER SERVICES PROVIDED BY THE INDEPENDENT AUDITOR SECTION I - POLICY PURPOSE AND APPLICABILITY The Pioneer Funds recognize the importance of maintaining the independence of their outside auditors. Maintaining independence is a shared responsibility involving Pioneer Investment Management, Inc ("PIM"), the audit committee and the independent auditors. The Funds recognize that a Fund's independent auditors: 1) possess knowledge of the Funds, 2) are able to incorporate certain services into the scope of the audit, thereby avoiding redundant work, cost and disruption of Fund personnel and processes, and 3) have expertise that has value to the Funds. As a result, there are situations where it is desirable to use the Fund's independent auditors for services in addition to the annual audit and where the potential for conflicts of interests are minimal. Consequently, this policy, which is intended to comply with Rule 210.2-01(C)(7), sets forth guidelines and procedures to be followed by the Funds when retaining the independent audit firm to perform audit, audit-related tax and other services under those circumstances, while also maintaining independence. Approval of a service in accordance with this policy for a Fund shall also constitute approval for any other Fund whose pre-approval is required pursuant to Rule 210.2-01(c)(7)(ii). In addition to the procedures set forth in this policy, any non-audit services that may be provided consistently with Rule 210.2-01 may be approved by the Audit Committee itself and any pre-approval that may be waived in accordance with Rule 210.2-01(c)(7)(i)(C) is hereby waived. Selection of a Fund's independent auditors and their compensation shall be determined by the Audit Committee and shall not be subject to this policy. SECTION II - POLICY ---------------- -------------------------------- ------------------------------------------------- SERVICE SERVICE CATEGORY DESCRIPTION SPECIFIC PRE-APPROVED SERVICE SUBCATEGORIES CATEGORY ---------------- -------------------------------- ------------------------------------------------- I. AUDIT Services that are directly o Accounting research assistance SERVICES related to performing the o SEC consultation, registration independent audit of the Funds statements, and reporting o Tax accrual related matters o Implementation of new accounting standards o Compliance letters (e.g. rating agency letters) o Regulatory reviews and assistance regarding financial matters o Semi-annual reviews (if requested) o Comfort letters for closed end offerings ---------------- -------------------------------- ------------------------------------------------- II. Services which are not o AICPA attest and agreed-upon procedures AUDIT-RELATED prohibited under Rule o Technology control assessments SERVICES 210.2-01(C)(4) (the "Rule") o Financial reporting control assessments and are related extensions of o Enterprise security architecture the audit services support the assessment audit, or use the knowledge/expertise gained from the audit procedures as a foundation to complete the project. In most cases, if the Audit-Related Services are not performed by the Audit firm, the scope of the Audit Services would likely increase. The Services are typically well-defined and governed by accounting professional standards (AICPA, SEC, etc.) ---------------- -------------------------------- ------------------------------------------------- ------------------------------------- ------------------------------------ AUDIT COMMITTEE APPROVAL POLICY AUDIT COMMITTEE REPORTING POLICY ------------------------------------- ------------------------------------ o "One-time" pre-approval o A summary of all such for the audit period for all services and related fees pre-approved specific service reported at each regularly subcategories. Approval of the scheduled Audit Committee independent auditors as meeting. auditors for a Fund shall constitute pre approval for these services. ------------------------------------- ------------------------------------ o "One-time" pre-approval o A summary of all such for the fund fiscal year within services and related fees a specified dollar limit (including comparison to for all pre-approved specified dollar limits) specific service subcategories reported quarterly. o Specific approval is needed to exceed the pre-approved dollar limit for these services (see general Audit Committee approval policy below for details on obtaining specific approvals) o Specific approval is needed to use the Fund's auditors for Audit-Related Services not denoted as "pre-approved", or to add a specific service subcategory as "pre-approved" ------------------------------------- ------------------------------------ SECTION III - POLICY DETAIL, CONTINUED ----------------------- --------------------------- ----------------------------------------------- SERVICE CATEGORY SERVICE CATEGORY SPECIFIC PRE-APPROVED SERVICE SUBCATEGORIES DESCRIPTION ----------------------- --------------------------- ----------------------------------------------- III. TAX SERVICES Services which are not o Tax planning and support prohibited by the Rule, o Tax controversy assistance if an officer of the Fund o Tax compliance, tax returns, excise determines that using the tax returns and support Fund's auditor to provide o Tax opinions these services creates significant synergy in the form of efficiency, minimized disruption, or the ability to maintain a desired level of confidentiality. ----------------------- --------------------------- ----------------------------------------------- ------------------------------------- ------------------------- AUDIT COMMITTEE APPROVAL POLICY AUDIT COMMITTEE REPORTING POLICY ------------------------------------- ------------------------- ------------------------------------- ------------------------- o "One-time" pre-approval o A summary of for the fund fiscal year all such services and within a specified dollar limit related fees 				 (including comparison 			 to specified dollar 			 limits) reported 			 quarterly. o Specific approval is needed to exceed the pre-approved dollar limits for these services (see general Audit Committee approval policy below for details on obtaining specific approvals) o Specific approval is needed to use the Fund's auditors for tax services not denoted as pre-approved, or to add a specific service subcategory as "pre-approved" ------------------------------------- ------------------------- SECTION III - POLICY DETAIL, CONTINUED ----------------------- --------------------------- ----------------------------------------------- SERVICE CATEGORY SERVICE CATEGORY SPECIFIC PRE-APPROVED SERVICE SUBCATEGORIES DESCRIPTION ----------------------- --------------------------- ----------------------------------------------- IV. OTHER SERVICES Services which are not o Business Risk Management support prohibited by the Rule, o Other control and regulatory A. SYNERGISTIC, if an officer of the Fund compliance projects UNIQUE QUALIFICATIONS determines that using the Fund's auditor to provide these services creates significant synergy in the form of efficiency, minimized disruption, the ability to maintain a desired level of confidentiality, or where the Fund's auditors posses unique or superior qualifications to provide these services, resulting in superior value and results for the Fund. ----------------------- --------------------------- ----------------------------------------------- --------------------------------------- ------------------------ AUDIT COMMITTEE APPROVAL POLICY AUDIT COMMITTEE REPORTING POLICY ------------------------------------- -------------------------- o "One-time" pre-approval o A summary of for the fund fiscal year within all such services and a specified dollar limit related fees 			 (including comparison 			 to specified dollar 				 limits) reported quarterly. o Specific approval is needed to exceed the pre-approved dollar limits for these services (see general Audit Committee approval policy below for details on obtaining specific approvals) o Specific approval is needed to use the Fund's auditors for "Synergistic" or "Unique Qualifications" Other Services not denoted as pre-approved to the left, or to add a specific service subcategory as "pre-approved" ------------------------------------- -------------------------- SECTION III - POLICY DETAIL, CONTINUED ----------------------- ------------------------- ----------------------------------------------- SERVICE CATEGORY SERVICE CATEGORY SPECIFIC PROHIBITED SERVICE SUBCATEGORIES DESCRIPTION ----------------------- ------------------------- ----------------------------------------------- PROHIBITED SERVICES Services which result 1. Bookkeeping or other services in the auditors losing related to the accounting records or independence status financial statements of the audit under the Rule. client* 2. Financial information systems design and implementation* 3. Appraisal or valuation services, fairness* opinions, or contribution-in-kind reports 4. Actuarial services (i.e., setting actuarial reserves versus actuarial audit work)* 5. Internal audit outsourcing services* 6. Management functions or human resources 7. Broker or dealer, investment advisor, or investment banking services 8. Legal services and expert services unrelated to the audit 9. Any other service that the Public Company Accounting Oversight Board determines, by regulation, is impermissible ----------------------- ------------------------- ----------------------------------------------- ------------------------------------------- ------------------------------ AUDIT COMMITTEE APPROVAL POLICY AUDIT COMMITTEE REPORTING POLICY ------------------------------------------- ------------------------------ o These services are not to be o A summary of all performed with the exception of the(*) services and related services that may be permitted fees reported at each if they would not be subject to audit regularly scheduled procedures at the audit client (as Audit Committee meeting defined in rule 2-01(f)(4)) level will serve as continual the firm providing the service. confirmation that has 				 not provided any restricted services. ------------------------------------------- ------------------------------ -------------------------------------------------------------------------------- GENERAL AUDIT COMMITTEE APPROVAL POLICY: o For all projects, the officers of the Funds and the Fund's auditors will each make an assessment to determine that any proposed projects will not impair independence. o Potential services will be classified into the four non-restricted service categories and the "Approval of Audit, Audit-Related, Tax and Other Services" Policy above will be applied. Any services outside the specific pre-approved service subcategories set forth above must be specifically approved by the Audit Committee. o At least quarterly, the Audit Committee shall review a report summarizing the services by service category, including fees, provided by the Audit firm as set forth in the above policy. -------------------------------------------------------------------------------- (2) Disclose the percentage of services described in each of paragraphs (b) through (d) of this Item that were approved by the audit committee pursuant to paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X. Non-Audit Services Beginning with non-audit service contracts entered into on or after May 6, 2003, the effective date of the new SEC pre-approval rules, the Trust's audit committee is required to pre-approve services to affiliates defined by SEC rules to the extent that the services are determined to have a direct impact on the operations or financial reporting of the Trust. For the years ended October 31, 2015 and 2014, there were no services provided to an affiliate that required the Trust's audit committee pre-approval. (f) If greater than 50 percent, disclose the percentage of hours expended on the principal accountants engagement to audit the registrant's financial statements for the most recent fiscal year that were attributed to work performed by persons other than the principal accountant's full-time, permanent employees. N/A (g) Disclose the aggregate non-audit fees billed by the registrants accountant for services rendered to the registrant, and rendered to the registrants investment adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser), and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant for each of the last two fiscal years of the registrant. The aggregate non-audit fees for the Trust were $17,500 payable to Deloitte & Touche LLP for the year ended October 31, 2015 and $17,500 for the year ended October 31, 2014. (h) Disclose whether the registrants audit committee of the board of trustees has considered whether the provision of non-audit services that were rendered to the registrants investment adviser (not including any subadviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser), and any entity controlling, controlled by, or under common control with the investment adviser that provides ongoing services to the registrant that were not pre-approved pursuant to paragraph (c)(7)(ii) of Rule 2-01 of Regulation S-X is compatible with maintaining the principal accountant's independence. The Fund's audit committee of the Board of Trustees has considered whether the provision of non-audit services that were rendered to the Affiliates (as defined) that were not pre- approved pursuant to paragraph (c)(7)(ii) of Rule 2-01 of Regulation S-X is compatible with maintaining the principal accountant's independence. ITEM 5. AUDIT COMMITTEE OF LISTED REGISTRANTS (a) If the registrant is a listed issuer as defined in Rule 10A-3 under the Exchange Act (17 CFR 240.10A-3), state whether or not the registrant has a separately-designated standing audit committee established in accordance with Section 3(a)(58)(A) of the Exchange Act (15 U.S.C. 78c(a)(58)(A)). If the registrant has such a committee, however designated, identify each committee member. If the entire board of directors is acting as the registrant's audit committee as specified in Section 3(a)(58)(B) of the Exchange Act (15 U.S.C. 78c(a)(58)(B)), so state. N/A (b) If applicable, provide the disclosure required by Rule 10A-3(d) under the Exchange Act (17 CFR 240.10A-3(d)) regarding an exemption from the listing standards for audit committees. N/A ITEM 6. SCHEDULE OF INVESTMENTS. File Schedule of Investments in securities of unaffiliated issuers as of the close of the reporting period as set forth in 210.1212 of Regulation S-X [17 CFR 210.12-12], unless the schedule is included as part of the report to shareholders filed under Item 1 of this Form. Included in Item 1 ITEM 7. DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR CLOSED-END MANAGEMENT INVESTMENT COMPANIES. A closed-end management investment company that is filing an annual report on this Form N-CSR must, unless it invests exclusively in non-voting securities, describe the policies and procedures that it uses to determine how to vote proxies relating to portfolio securities, including the procedures that the company uses when a vote presents a conflict between the interests of its shareholders, on the one hand, and those of the company's investment adviser; principal underwriter; or any affiliated person (as defined in Section 2(a)(3) of the Investment Company Act of 1940 (15 U.S.C. 80a-2(a)(3)) and the rules thereunder) of the company, its investment adviser, or its principal underwriter, on the other. Include any policies and procedures of the company's investment adviser, or any other third party, that the company uses, or that are used on the company's behalf, to determine how to vote proxies relating to portfolio securities. Not applicable to open-end management investment companies. ITEM 8. PORTFOLIO MANAGERS OF CLOSED-END MANAGEMENT INVESTMENT COMPANIES. (a) If the registrant is a closed-end management investment company that is filing an annual report on this Form N-CSR,provide the following information: (1) State the name, title, and length of service of the person or persons employed by or associated with the registrant or an investment adviser of the registrant who are primarily responsible for the day-to-day management of the registrant's portfolio ("Portfolio Manager"). Also state each Portfolio Manager's business experience during the past 5 years. Not applicable to open-end management investment companies. ITEM 9. PURCHASES OF EQUITY SECURITIES BY CLOSED-END MANAGEMENT INVESTMENT COMPANY AND AFFILIATED PURCHASERS. (a) If the registrant is a closed-end management investment company, in the following tabular format, provide the information specified in paragraph (b) of this Item with respect to any purchase made by or on behalf of the registrant or any affiliated purchaser, as defined in Rule 10b-18(a)(3) under the Exchange Act (17 CFR 240.10b-18(a)(3)), of shares or other units of any class of the registrant's equity securities that is registered by the registrant pursuant to Section 12 of the Exchange Act (15 U.S.C. 781). Not applicable to open-end management investment companies. ITEM 10. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS. Describe any material changes to the procedures by which shareholders may recommend nominees to the registrant's board of directors, where those changes were implemented after the registrant last provided disclosure in response to the requirements of Item 407(c)(2)(iv) of Regulation S-R(17 CFR 229.407)(as required by Item 22(b)(15)) of Schedule 14A (17 CFR 240.14a-101), or this Item. There have been no material changes to the procedures by which the shareholders may recommend nominees to the registrant's board of directors since the registrant last provided disclosure in response to the requirements of Item 407(c)(2)(iv) of Regulation S-R of Schedule 14(A) in its definitive proxy statement, or this item. ITEM 11. CONTROLS AND PROCEDURES. (a) Disclose the conclusions of the registrant's principal executive and principal financials officers, or persons performing similar functions, regarding the effectiveness of the registrant's disclosure controls and procedures (as defined in Rule 30a-3(c) under the Act (17 CFR 270.30a-3(c))) as of a date within 90 days of the filing date of the report that includes the disclosure required by this paragraph, based on the evaluation of these controls and procedures required by Rule 30a-3(b) under the Act (17 CFR 270.30(a)-3(b) and Rules 13a-15(b) or 15d-15(b) under the Exchange Act (17 CFR 240.13a-15(b) or 240.15d-15(b)). The registrant's principal executive officer and principal financial officer have concluded that the registrant's disclosure controls and procedures are effective based on the evaluation of these controls and procedures as of a date within 90 days of the filing date of this report. (b) Disclose any change in the registrant's internal control over financial reporting (as defined in Rule 30a-3(d) under the Act (17CFR 270.30a-3(d)) that occured during the second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting. There were no significant changes in the registrant's internal control over financial reporting that occurred during the second fiscal quarter of the period covered by this report that have materially affected, or are reasonably likely to materially affect, the registrant's internal control over financial reporting. The registrant's principal executive officer and principal financial officer, however, voluntarily are reporting the following information: In August of 2006 the registrant's investment adviser enhanced its internal procedures for reporting performance information required to be included in prospectuses. Those enhancements involved additional internal controls over the appropriateness of performance data generated for this purpose. Such enhancements were made following an internal review which identified prospectuses relating to certain classes of shares of a limited number of registrants where, inadvertently, performance information not reflecting the deduction of applicable sales charges was included. Those prospectuses were revised, and the revised prospectuses were distributed to shareholders. ITEM 12. EXHIBITS. (a) File the exhibits listed below as part of this Form. Letter or number the exhibits in the sequence indicated. (1) Any code of ethics, or amendment thereto, that is the subject of the disclosure required by Item 2, to the extent that the registrant intends to satisfy the Item 2 requirements through filing of an exhibit. (2) A separate certification for each principal executive officer and principal financial officer of the registrant as required by Rule 30a-2(a) under the Act (17 CFR 270.30a-2(a)) , exactly as set forth below: Filed herewith. SIGNATURES [See General Instruction F] Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. (Registrant) Pioneer Series Trust VI By (Signature and Title)* /s/ Lisa M. Jones Lisa M. Jones, President & Chief Executive Officer Date December 30, 2015 Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated. By (Signature and Title)* /s/ Lisa M. Jones Lisa M. Jones, President & Chief Executive Officer Date December 30, 2015 By (Signature and Title)* /s/ Mark Bradley Mark Bradley, Treasurer & Chief Accounting & Financial Officer Date December 30, 2015 * Print the name and title of each signing officer under his or her signature.