Information about the purchase and redemption of Fund shares, taxes, and payments to broker/dealers and financial intermediaries

Purchase and redemption of Fund shares

You may purchase or redeem shares of a Fund on any day that the New York Stock Exchange (NYSE) is open for business (Business Day). Shares may be purchased or redeemed: through your financial intermediary or by exchanging shares you own in one Optimum Fund for shares of the same class of another Optimum Fund.

For Class A and Class C shares, the minimum initial investment is generally $1,000 and subsequent investments can be made for as little as $100. The minimum initial investment for IRAs, Uniform Gifts/Transfers to Minors Act accounts, direct deposit purchase plans, and automatic investment plans is $250 and through Coverdell Education Savings Accounts is $500, and subsequent investments in these accounts can be made for as little as $25. Under certain circumstances, the initial and subsequent investment minimums may be waived. In particular, certain accounts held in omnibus, advisory, or asset allocation programs or programs offered by certain intermediaries may be opened below the minimum stated account balance. Your participating securities dealer or other financial intermediary may have different account and investment requirements.

There is no minimum initial purchase requirement for Institutional Class shares, but Institutional Class shares are available for purchase only by the following:

Tax information

A Fund's distributions generally are taxable to you as ordinary income, capital gains, or some combination of both, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an IRA, in which case your distributions may be taxed as ordinary income when withdrawn from the tax-advantaged account.

Payments to broker/dealers and other financial intermediaries

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

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More information on the Funds' risks and portfolio holdings

More information on the Funds' risks

Investing in any mutual fund involves risk, including the risk that you may receive little or no return on your investment, and the risk that you may lose part or all of the money you invest. Before you invest in a Fund, you should carefully evaluate the risks associated with that Fund.

Each Fund has principal investment strategies that come with inherent risks. Each Fund's principal risks are identified in its Fund summary under the heading “What are the principal risks of investing in the Fund?” and are described in more detail below. Also described below are additional risks to which each Fund may be subject by investing in various types of securities or engaging in various practices. Unless otherwise indicated, each risk applies to all of the Funds. Please see the SAI for a further discussion of these risks and other risks not discussed here.

Market risk — Market risk is the risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Equity risk — Equity risk is the risk that stocks and other equity securities generally fluctuate in value more than bonds and may decline in value over short or over extended periods, regardless of the success or failure of a company's operations.

Fixed income risk — Optimum Fixed Income Fund is subject to, and to the extent that a Fund invests a substantial amount of its assets in fixed income securities, the Fund is subject to, the following risks:

Credit risk — Credit risk is the risk that the issuer of a debt security, including a governmental issuer or an entity that insures a bond, may be unable to make interest payments and/or repay principal in a timely manner. Changes in an issuer's financial strength or in a security's credit rating may affect a security's value, which would impact Fund performance.

Interest rate risk — Interest rate risk is the risk that the prices of bonds and other fixed income securities will increase as interest rates fall and decrease as interest rates rise. Interest rate changes are influenced by a number of factors, such as government policy, monetary policy, inflation expectations, and the supply and demand of bonds. Bonds and other fixed income securities with longer maturities or duration generally are more sensitive to interest rate changes. A Fund may be subject to a greater risk of rising interest rates when interest rates are low or inflation rates are high or rising.

High yield (junk) bond risk — High yield, high-risk bonds (commonly known as junk bonds), while generally having higher yields, are subject to reduced creditworthiness of issuers, increased risks of default, and a more limited and less liquid secondary market. These securities may also be subject to greater price volatility and risk of loss of income and principal than are higher rated securities because they are rated below investment grade. Lower rated and unrated fixed income securities tend to reflect short-term corporate and market developments to a greater extent than higher rated fixed income securities, which react primarily to fluctuations in the general level of interest rates. Fixed income securities of this type are considered to be of poor standing and primarily speculative. Such securities are subject to a substantial degree of credit risk.

Mortgage-backed and asset-backed securities risk — Mortgage-backed and asset-backed securities, like other fixed income securities, are subject to credit risk and interest rate risk, and may also be subject to prepayment risk and extension risk. Mortgage-backed and asset-backed securities can be highly sensitive to interest rate changes. As a result, small movements in interest rates can substantially impact the value and liquidity of these securities. Prepayment risk is the risk that the principal on mortgage-backed or asset-backed securities may be prepaid at any time, which will reduce the yield and market value of the securities and may cause the series to reinvest the proceeds in lower yielding securities. Extension risk is the risk that principal on mortgage-backed or asset-backed securities will be repaid more slowly than expected, which may reduce the proceeds available for reinvestment in higher yielding securities and may cause the security to experience greater volatility due to the extended maturity of the security. When interest rates rise, the value of mortgage-backed and asset-backed securities can be expected to decline. When interest rates go down, however, the value of these securities may not increase as much as other fixed income securities due to borrowers refinancing their loans at lower interest rates or prepaying their loans. In addition, mortgage-backed and asset-backed securities may decline in value, become more volatile, face difficulties in valuation, or experience reduced liquidity due to changes in general economic conditions. During periods of economic downturn, for example, underlying borrowers may not make timely payments on their loans and the value of property that secures the loans may decline in value such that it is worth less than the amount of the associated loans. If the collateral securing a mortgage-backed or asset-backed security is insufficient to repay the loan, a series could sustain a loss. Such risks generally will be heightened where a mortgage-backed or asset-backed security includes “subprime” loans. Although mortgage-backed securities are often supported by government guarantees or private insurance, there can be no guarantee that those obligations will be met. Furthermore, in certain economic conditions, loan servicers, loan originators and other participants in the market for mortgage-backed and other asset-backed securities may be unable to receive sufficient funding, impairing their ability to perform their obligations on the loans. Certain mortgage-backed or asset-backed securities may be more susceptible to these risks than other mortgage-backed, asset-backed, or fixed-income securities. For example, a series' investments in CMOs, REMICs, and stripped mortgage-backed securities are generally highly susceptible to interest rate risk, prepayment risk, and extension risk. At times, these investments may be difficult to value and/or illiquid. Some classes of CMOs and REMICs may have preference in receiving principal or interest payments relative to more junior classes. The market prices and yields of these junior classes will generally be more volatile than more senior classes and will be more susceptible to interest rate risk, prepayment risk, and extension risk than more senior classes. Classes that receive interest only (IOs) will generally

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decrease in value if interest rates decline or prepayment rates increase. Classes that receive principal only (POs) will generally decrease in value if interest rates increase or prepayment rates decrease. These changes in value can be substantial and could cause a series to lose the entire value of its investment in CMOs, REMICs, and stripped mortgage-backed securities.

Loans and other indebtedness risk — Loans and other indebtedness risk is the risk that a Fund will not receive payment of principal, interest, and other amounts due in connection with these investments and will depend primarily on the financial condition of the borrower and the lending institution. Bank loans are an interest in a loan or other indebtedness, such as an assignment, that entitles the acquirer of such interest to payments of interest, principal, and/or other amounts due under the structure of the loan or other indebtedness. In addition to being structured as secured or unsecured loans, such investments could be structured as novations or assignments, or represent trade or other claims owed by a company to a supplier. Some investments in bank loans may also include a “LIBOR floor” or an “IBOR floor.” Bank loans with such floors generally ensure investors a minimum level of coupon payment, but the coupon rates for these types of securities may not adjust upward as quickly when rates rise since the coupon rate only adjusts when interest rates go higher than the applied floor.

Large-capitalization company risk — Optimum Large Cap Growth Fund and Optimum Large Cap Value Fund are subject to, and to the extent that a Fund invests a substantial amount of its assets in large-capitalization companies, the Fund is subject to, large-capitalization company risk. Large-capitalization company risk is the risk that large-capitalization companies tend to go in and out of favor based on market and economic conditions. Large-capitalization companies tend to be less volatile than companies with smaller market capitalizations. This potentially lower risk means that a Fund's share price may not rise as much as the share prices of funds that focus on smaller capitalization companies.

Small- and mid-market capitalization company risk — Optimum Small-Mid Cap Growth Fund and Optimum Small-Mid Cap Value Fund are subject to, and to the extent that a Fund invests a substantial amount of its assets in small- and mid-market capitalization companies, the Fund is subject to, small-and mid-market capitalization risk. Small- and mid-market capitalization company risk is greater for investments in small- and mid-market capitalization companies because they generally are more vulnerable than larger companies to adverse business or economic developments and they may have more limited resources. Their managements may lack depth and experience. Smaller companies also may have narrower product lines and more limited trading markets for their stock, as compared with larger companies. Their securities may be less well known and trade less frequently and in more limited volume than the securities of larger, more established companies. In addition, small- and mid-market capitalization companies are typically subject to greater changes in earnings and business prospects than larger companies. Consequently, the prices of smaller company stocks tend to rise and fall in value more frequently than the stocks of larger companies. Investments in small- and mid-market capitalization companies, which often borrow money to finance operations, may also be adversely affected by rising interest rates. Additionally, many small-capitalization stocks trade less frequently and in smaller volume than exchange-listed stocks. Some small-capitalization companies may be unseasoned companies that have been in operation less than three years, including operation of any predecessors. Their securities may have limited liquidity and their prices may be very volatile.

Foreign risk — Optimum International Fund is subject to, and to the extent that a Fund invests a substantial amount of its assets in foreign securities, the Fund is subject to, foreign risk. Foreign risk is the risk that a Fund's investments in foreign securities, including ADRs, may be adversely affected by political developments, changes in currency exchange rates, foreign economic conditions, the imposition of economic or trade sanctions, or inadequate regulatory and accounting standards. In addition, there is the possibility of expropriation, nationalization, or confiscatory taxation, taxation of income earned in foreign nations or other taxes imposed with respect to investments in foreign nations, foreign exchange controls, which may include suspension of the ability to transfer currency from a given country, and default in foreign government securities. As a result of these factors, foreign securities markets may be less liquid and more volatile than US markets and a Fund may experience difficulties and delays in converting foreign currencies back into US dollars. Such events may cause the value of certain foreign securities to fluctuate widely and may make it difficult to accurately value foreign securities. In addition, the costs of buying, selling, and holding foreign securities, including brokerage, tax, and custody costs, may be higher than those involved in domestic transactions.

Currency risk — Currency risk is the risk that the value of a Fund's investments may be negatively affected by changes in foreign currency exchange rates. Adverse changes in exchange rates may reduce or eliminate any gains produced by investments that are denominated in foreign currencies and may increase losses.

Emerging markets risk — Emerging markets risk is the risk that risks associated with international investing will be greater in emerging markets than in more developed foreign markets because, among other things, emerging markets may have less stable political and economic environments. In addition, in many emerging markets, there is substantially less publicly available information about issuers and the information that is available tends to be of lesser quality. Economic markets and structures tend to be less mature and diverse and the securities markets, which are subject to less government regulation or supervision, may also be smaller, less liquid, and subject to greater price volatility.

As a result of increasingly interconnected global economies and financial markets, armed conflict between countries or armed conflict in a geographic region has the potential to adversely impact a Fund's investments. Such conflicts and other corresponding events could result in increased volatility, reduced liquidity, and overall uncertainty. The negative impacts may be particularly acute in certain sectors or in markets for certain securities and

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More information on the Funds' risks and portfolio holdings

commodities. Such conflicts also may result in a negative impact on a Fund's investments, even beyond any direct investment exposure the Fund may have to issuers located in or with significant exposure to an impacted country or geographic region.

Investment style risk — Investment style risk is the risk that a sub-advisor may primarily use a particular style or set of styles — either growth or value styles — to select investments for a Fund. Those styles may be out of favor or may not produce the best results over short or longer time periods. They may also increase the volatility of a Fund's share price.

Growth investing risk — Optimum Large Cap Growth Fund and Optimum Small-Mid Cap Growth Fund are subject to, and to the extent that a Fund invests a substantial amount of its assets in growth stocks, the Fund is subject to, growth investing risk. Growth stocks tend to be more expensive relative to their earnings or assets compared to other types of stocks. These companies tend to invest a high portion of earnings in their businesses and may lack the dividends of value stocks that can cushion stock prices in falling markets. As a result, growth stocks tend to be sensitive to changes in their earnings and more volatile than other types of stocks.

Value investing risk — Optimum Large Cap Value Fund and Optimum Small-Mid Cap Value Fund are subject, and to the extent that a Fund invests a substantial amount of its assets in value stocks, the Fund is subject to, to value investing risk. Value stocks tend to be inexpensive relative to their earnings or assets compared to other types of stocks. However, value stocks can continue to be inexpensive for long periods of time and may not ever realize their full value.

Issuer specific risk — Issuer specific risk is the risk that the value of an individual security or particular type of security can be more volatile than the market as a whole and can perform differently from the market as a whole. A Fund could lose all of its investment in a company's securities.

Portfolio management risk — Portfolio management risk is the risk that the sub-advisors' (and, where applicable, the Manager's) strategies and their securities selections might fail to produce the intended result or might underperform the markets, the relevant indices, or the securities selected by other funds with similar investment objectives and investment strategies. The securities and sectors selected may vary from the securities and sectors included in the relevant index.

Multiple advisor risk — Multiple advisor risk is the risk that each Fund employs multiple investment advisors, each of which independently chooses and maintains a portfolio of securities for its respective Fund and is responsible for investing a specific allocated portion of the Fund's assets. The same security may be held in different portions of a Fund or may be acquired for one portion of a Fund at a time when an investment advisor to another portion deems it appropriate to dispose of the security from that other portion. Similarly, under some market conditions, one investment advisor may believe that temporary, defensive investments in short-term instruments or cash are appropriate when the other investment advisor believes continued exposure to the equity markets is appropriate for its allocated portion of a Fund. Because each investment advisor directs the trading for its own portion of a Fund, and does not aggregate its transactions with those of the other investment advisor(s), a Fund may incur higher brokerage costs than would be the case if a single investment advisor were managing the entire Fund.

Quantitative model risk — The risk that funds that are managed according to a quantitative model may perform differently from the market as a whole based on the factors used in the model, the weight placed on each factor and changes from the factors' historical trends. Due to the significant role technology plays in a quantitative model, use of a quantitative model carries the risk of potential issues with the design, coding, implementation or maintenance of the computer programs, data and/or other technology used in the quantitative model. These issues could negatively impact investment returns. Such risks should be viewed as an inherent element of investing in an investment strategy that relies heavily upon a quantitative model.

Derivatives risk — Optimum International Fund and Optimum Fixed Income Fund are subject to, and to the extent that a Fund invests a substantial amount of its assets in derivatives, the Fund is subject to, derivatives risk. Derivatives risk is the possibility that a Fund may experience a significant loss if it employs a derivatives strategy (including a strategy involving equity-linked securities, futures, options, forward foreign currency contracts, or swaps such as interest rate swaps, index swaps, or credit default swaps) related to a security, index, reference rate, or other asset or market factor (collectively, a “reference instrument”) and that reference instrument moves in the opposite direction from what the portfolio manager had anticipated. If a market or markets, or prices of particular classes of investments, move in an unexpected manner, a Fund may not achieve the anticipated benefits of the transaction and it may realize losses. Derivatives also involve additional expenses, which could reduce any benefit or increase any loss to a Fund from using the strategy. In addition, changes in government regulation of derivatives could affect the character, timing, and amount of a Fund's taxable income or gains. A Fund's transactions in derivatives may be subject to one or more special tax rules. These rules may: (i) affect whether gains and losses recognized by a Fund are treated as ordinary or capital or as short-term or long-term, (ii) accelerate the recognition of income or gains to the Fund, (iii) defer losses to the Fund, and (iv) cause adjustments in the holding periods of the Fund's securities. A Fund's use of derivatives may be limited by the requirements for taxation of the Fund as a regulated investment company.

Investing in derivatives may subject a Fund to counterparty risk. Please refer to “Counterparty risk” for more information. Other risks include illiquidity, mispricing or improper valuation of the derivatives contract, and imperfect correlation between the value of the derivatives instrument and the underlying reference instrument so that a Fund may not realize the intended benefits. In addition, since there can be no assurance that a liquid secondary market will

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exist for any derivatives instrument purchased or sold, a Fund may be required to hold a derivatives instrument to maturity and take or make delivery of an underlying reference instrument that the Manager would have otherwise attempted to avoid, which could result in losses. When used for hedging, the change in value of the derivatives instrument may also not correlate specifically with the currency, rate, or other risk being hedged, in which case a Fund may not realize the intended benefits.

These types of transactions will be used for a number of reasons, including: to manage a Fund's exposure to changes in securities prices and foreign currencies; to efficiently adjust a Fund's overall exposure to certain markets; in an effort to enhance income; to protect the value of portfolio securities (“hedging”); and to serve as a cash management tool. When a derivative security is used as a hedge against an offsetting position that a Fund also holds, any loss generated by the derivative security should be substantially offset by gains on the hedged instrument, and vice versa. However, a lack of correlation between the value of a derivative and the assets being hedged could render a Fund's hedging strategy unsuccessful and could result in losses. To the extent that a Fund uses a derivative security for purposes other than as a hedge, the Fund is directly exposed to the risks of that derivative security and any loss generated by the derivative security will not be offset by a gain.

Counterparty risk — Counterparty risk is the risk that if a Fund enters into a derivatives contract (such as a futures, options, or swap contract) or a repurchase agreement, the counterparty to such a contract or agreement may fail to perform its obligations under the contract or agreement due to financial difficulties (such as a bankruptcy or reorganization). As a result, the Fund may experience significant delays in obtaining any recovery, may obtain only a limited recovery, or may obtain no recovery at all. In addition, a Fund may lend up to 25% of its assets to qualified broker/dealers or institutional investors for their use relating to short sales or other security transactions, and such transactions expose the Fund to counterparty risk as further described in the Funds' SAI.

Leveraging risk — Leveraging risk is the risk that certain fund transactions, such as reverse repurchase agreements, short sales, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivatives instruments, may give rise to leverage, causing a Fund to be more volatile than if it had not been leveraged. While it is anticipated that leverage may increase profitability, it may also accentuate the consequences of adverse price movements, resulting in increased losses.

Liquidity risk — Liquidity risk is the risk that the possibility that securities cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may trade at a discount from comparable, more liquid investments, and may be subject to wide fluctuations in market value. A Fund also may not be able to dispose of illiquid investments at a favorable time or price during periods of infrequent trading of an illiquid investment.

Industry and sector risk — Industry and sector risk is the risk that the value of securities in a particular industry/sector or the value of an individual stock or bond will decline because of changing expectations for the performance of that industry/sector or for the individual company issuing the stock or bond. A Fund that concentrates its investments in a particular industry or individual security generally is subject to greater risks than a Fund that is not concentrated.

IBOR risk — IBOR risk is the risk that changes related to the use of the London Interbank Offered Rate (LIBOR) or similar interbank offered rates (“IBORs,” such as the Euro Overnight Index Average (EONIA)) could have adverse impacts on financial instruments that reference such rates. While some instruments may contemplate a scenario where LIBOR or a similar rate is no longer available by providing for an alternative rate setting methodology, not all instruments have such fallback provisions and the effectiveness of replacement rates is uncertain. The abandonment of LIBOR and similar rates could affect the value and liquidity of instruments that reference such rates, especially those that do not have fallback provisions. The use of alternative reference rate products may impact investment strategy performance.

Inflation risk — Inflation risk is the risk that the return from your investments will be less than the increase in the cost of living due to inflation, thus preventing you from reaching your financial goals.

Opportunity risk — Opportunity risk is the risk of missing out on an investment opportunity because the assets necessary to take advantage of it are tied up in less profitable investments.

Valuation risk — Valuation risk is the risk that a less liquid secondary market may make it more difficult for a Fund to obtain precise valuations of certain securities. During periods of reduced liquidity, judgment plays a greater role in valuing less liquid securities.

Information risk — Information risk is the risk that key information about a security is inaccurate or unavailable.

Real estate industry risk — Real estate industry risk includes, among others: possible declines in the value of real estate; risks related to general and local economic conditions; possible lack of availability of mortgage funds; overbuilding; extended vacancies of properties; increases in competition, property taxes, and operating expenses; changes in zoning laws; costs resulting from the cleanup of, and liability to third parties resulting from, environmental problems; casualty for condemnation losses; uninsured damages from floods, earthquakes, or other natural disasters; limitations on and variations in rents; and changes in interest rates. REITs are subject to substantial cash flow dependency, defaults by borrowers, self-liquidation, and the

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More information on the Funds' risks and portfolio holdings

risk of failing to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (Internal Revenue Code), or other similar statute in non-US countries and/or to maintain exemptions from the Investment Company Act of 1940, as amended.

Convertible securities risk — Convertible securities risk is the risk that the value of convertible securities fluctuates in relation to changes in interest rates and the value of the underlying common stock.

Short sales risk — Short sales risk involves transactions in which a Fund sells a security it does not own and, at the time the short sale is effected, the Fund incurs an obligation to replace the security borrowed no matter what its price may be at the time the Fund delivers it to the lender. Short positions in securities may be more risky than long positions (purchases). If a Fund has a short position in a security and the price of such security increases, the Fund will lose money on its short position. Furthermore, during the time when the Fund has a short position in such security, the Fund must borrow that security in order to make delivery on the short sale, which raises the cost to the Fund of entering into the transaction. A Fund is therefore subject to the risk that a third party may fail to honor the terms of its contract with the Fund related to the securities borrowing. Short sales also involve the risk of an unlimited increase in the market price of the security sold short, which would result in a theoretically unlimited loss.

Initial public offering risk — Optimum Large Cap Growth Fund, Optimum Large Cap Value Fund, Optimum Small-Mid Cap Growth Fund, Optimum Small-Mid Cap Value Fund and Optimum International Fund are subject to initial public offering risk. Initial public offering risk is the risk that the volume of initial public offerings (“IPOs”) and the levels at which the newly issued stocks trade in the secondary market are affected by the performance of the stock market overall. If IPOs are brought to the market, availability may be limited and a Fund may not be able to buy any shares at the offering price, or if it is able to buy shares, it may not be able to buy as many shares at the offering price as it would like. In addition, the prices of securities involved in IPOs are often subject to greater and more unpredictable price changes than more established stocks.

Portfolio turnover risk — Portfolio turnover risk is the risk that the Funds do not restrict the frequency of trading to limit expenses or to minimize the tax effect that a Fund's distributions may have on shareholders. A Fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies. Frequent trading can result in a portfolio turnover in excess of 100% (high portfolio turnover). High portfolio turnover may increase brokerage commissions paid and could generate taxes for shareholders on realized investment gains.

Government and regulatory risks — Government and regulatory risks are the risks that government or regulatory authorities may take actions that could adversely affect various sectors of the securities markets and affect fund performance. Government involvement in the private sector may, in some cases, include government investment in, or ownership of, companies in certain commercial business sectors; wage and price controls; or imposition of trade barriers and other protectionist measures. For example, an economic or political crisis may lead to price controls, forced mergers of companies, expropriation, the creation of government monopolies, foreign exchange controls, the introduction of new currencies (and the redenomination of financial obligations into those currencies), or other measures that could be detrimental to the investments of a Fund.

Cybersecurity risk — Cybersecurity risk is the risk that through the increased use of technologies, such as the internet and the dependence on computer systems, to perform necessary business functions, the Funds and their service providers may have become more susceptible to operational and related risks through breaches in cybersecurity. A cybersecurity incident may refer to intentional or unintentional events that allow an unauthorized party to gain access to Fund assets, customer data, or proprietary information, or cause a Fund or Fund service providers (including, but not limited to, the Manager, distributor, fund accountants, custodian, transfer agent, and financial intermediaries) to suffer data corruption or lose operational functionality. A cybersecurity incident could, among other things, result in the loss or theft of customer data or funds, customers or employees being unable to access electronic systems (denial of services), loss or theft of proprietary information or corporate data, physical damage to a computer or network system, or remediation costs associated with system repairs.

Natural disaster and epidemic risk — Natural disaster and epidemic risk is the risk that the value of a Fund's investments may be negatively affected by natural disasters, epidemics, or similar events. Natural or environmental disasters, such as earthquakes, fires, floods, hurricanes, tsunamis, and other severe weather-related phenomena generally, and widespread disease, including pandemics and epidemics, have been and can be highly disruptive to economies and markets, adversely impacting individual companies, sectors, industries, markets, currencies, interest and inflation rates, credit ratings, investor sentiment, and other factors affecting the value of a Fund's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region are increasingly likely to adversely affect markets, issuers, and/or foreign exchange rates in other countries. These disruptions could prevent a Fund from executing advantageous investment decisions in a timely manner and could negatively impact the Fund's ability to achieve its investment objective.

Disclosure of portfolio holdings information

A description of the Funds' policies and procedures with respect to the disclosure of their portfolio securities is available in the SAI.

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Who manages the Funds

Investment manager

The Manager, located at 100 Independence, 610 Market Street, Philadelphia, PA, 19106-2354, is the Funds' investment manager. The Manager and its predecessors have been managing pooled investment vehicles since 1938. The Manager is a series of Macquarie Investment Management Business Trust (MIMBT), which is a Delaware statutory trust. MIMBT is a wholly owned subsidiary of Macquarie Group Limited and a part of Macquarie Asset Management (MAM). MAM is the marketing name for certain companies comprising the asset management division of Macquarie Group Limited. MAM is an integrated asset manager across public and private markets offering a diverse range of capabilities, including real assets, real estate, credit, equities and multi-asset solutions. As of March 31, 2025, MAM managed approximately $588 billion in assets for institutional and individual clients.

As the Funds' investment manager, the Manager has overall responsibility for the general management of the Funds, which includes selecting the Funds' sub-advisors and monitoring each Fund and sub-advisor to ensure that investment activities remain consistent with a Fund's investment objective. A team is responsible for conducting ongoing investment reviews with each sub-advisor and for developing the criteria by which Fund performance is measured. The Manager has hired LPL Financial LLC (LPL), a registered broker/dealer and investment advisor, as a consultant to assist with this process.

For the last fiscal year, each Fund paid the Manager the following aggregate fees, net of waivers (as applicable), based on such Fund's average daily net assets:

The management fee for each Fund, as a percentage of average daily net assets, declines as assets increase above designated levels. The Manager pays the consulting fees out of its assets as described in the Funds' SAI.

A discussion regarding the basis for the Board's approvals of the Funds' investment advisory and sub-advisory agreements is available on the Funds' website and is filed with the US Securities and Exchange Commission (SEC) on the Funds' Form N-CSR for the fiscal period ended March 31, 2025.

On April 21, 2025, Macquarie Group Limited, the parent company of the Manager, a series of MIMBT, together with certain of its affiliates, and Nomura, announced that they had entered into an agreement for Nomura to acquire the US and European public investments asset management business of Macquarie Asset Management. The transaction is subject to customary closing conditions, including the receipt of applicable regulatory approvals. Subject to such approvals and the satisfaction of these conditions, the transaction is expected to close on or about October 31, 2025.

Under the Investment Company Act of 1940, as amended, the closing of the Nomura transaction will result in the automatic termination of each Fund's investment advisory agreement with the Manager and the sub-advisory agreements. In anticipation of this automatic termination, on June 18, 2025, the Board approved a new investment advisory agreement for each Fund that would go into effect at the closing of the transaction. The Board recommends that shareholders of each Fund approve the new investment advisory agreement at a meeting of shareholders scheduled to occur on September 10, 2025. Proxy solicitation materials related to this meeting have been made available to shareholders that held shares of the Funds at the close of business on July 3, 2025. At the Board Meeting, the Board also unanimously approved an interim investment advisory agreement between each Fund and the Manager (the Interim Agreement), which would become effective at the time of the transaction in the event that Fund shareholders have not approved the new advisory agreement but the transaction has closed, under which the Manager could provide investment advisory services to a Fund for up to the earlier of 150 days from the effective date of the Interim Agreement or the date of shareholder approval of the new advisory agreement for such Fund.

On September 19, 2024, the SEC announced that MIMBT, of which the Manager is a series, had entered into a settlement agreement with the SEC consenting to an order (Settlement Order) relating to a legacy investment strategy, the Absolute Return Mortgage-Backed Securities Strategy (ARMBS Strategy). MIMBT no longer offers the ARMBS Strategy. MIMBT agreed to the Settlement Order without admitting or denying the SEC's findings.

Under the Settlement Order, the SEC found that, between January 2017 and April 2021 (Period): (i) MIMBT valued certain collateralized mortgage-backed obligations (CMOs) at inflated prices; (ii) MIMBT executed dealer-interposed and internal cross trades of those CMOs between registered investment company clients and other clients at prices that deviated from market prices; (iii) certain disclosures of MIMBT relating to performance, valuation, liquidity and cross trading contained false and misleading statements and omissions; and (iv) MIMBT failed to implement policies and procedures relating to valuation, conflicts of interest and cross trades.

As part of the settlement, MIMBT was ordered to cease and desist from committing or causing any violations of certain statutory provisions and SEC rules. A copy of the Settlement Order is available on the SEC's website at https://www.sec.gov/files/litigation/admin/2024/ia-6709.pdf.

MIMBT has made a payment to Optimum Fixed Income Fund in connection with cross trades and valuation of CMOs during the Period.

MIMBT has been ordered to pay a civil penalty to the SEC, as well as disgorgement of management fees in respect of Optimum Fixed Income Fund relating to the Period and interest. The SEC may in its discretion make payments to shareholders of Optimum Fixed Income Fund pursuant to a Fair Fund. If the SEC creates a Fair Fund, information regarding the operation of the Fair Fund will be made available to eligible shareholders.

Sub-advisors and portfolio managers

Each Fund's investments are selected by one or more sub-advisors. The following identifies and describes each Fund's sub-advisors, identifies each Fund's portfolio managers, and describes each portfolio manager's business experience. Each sub-advisor is paid by the Manager.

Optimum Large Cap Growth Fund

American Century, located at 4500 Main Street, Kansas City, MO, 64111, was founded in 1958 and has more than 65 years of investment management experience. American Century is a wholly owned subsidiary of American Century Companies, Inc. (ACC). The Stowers Institute for Medical Research

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Who manages the Funds

(SIMR) controls ACC by virtue of its beneficial ownership of more than 25% of the voting securities of ACC. SIMR is part of a not-for-profit biomedical research organization dedicated to finding the keys to the causes, treatments and prevention of disease. As of March 31, 2025, American Century had approximately $252 billion in assets under management. American Century has held its Fund responsibilities since July 2022.

Keith Lee (team lead), Jeff Bourke, and Tong Li are primarily responsible for the day-to-day management of American Century's portion of the Fund. Mr. Lee has been employed by American Century since 2001 and currently serves as Senior Vice President, Senior Portfolio Manager and Co-Chief Investment Officer, Global Growth Equity. Mr. Bourke has been employed by American Century since 2007 and currently serves as Vice President and Portfolio Manager. Mr. Tong Li has been employed by American Century since 2007 and currently serves as Portfolio Manager and Senior Quantitative Analyst.

Los Angeles Capital Management LLC (Los Angeles Capital) is headquartered at 11150 Santa Monica Blvd., Suite 200, Los Angeles, CA 90025. Los Angeles Capital has been registered as an investment advisor with the SEC since 2002 and provides investment management services to funds and other institutional clients. Los Angeles Capital is employee owned through its parent companies, LACM Holdings Inc. and LACM Equity LLC. Los Angeles Capital has a wholly owned subsidiary, LACM Global, Ltd., an entity formed in the UK and regulated by the Financial Conduct Authority. As of March 31, 2025, Los Angeles Capital's total assets under management were approximately $29.6 billion. Los Angeles Capital has held its Fund responsibilities since January 2023.

Hal W. Reynolds, Daniel Arche and Daniel E. Allen are primarily responsible for the day-to-day management of the investment program for Los Angeles Capital's portion of the Fund. Mr. Reynolds, CFA, Vice Chair and Senior Portfolio Manager, co-founded Los Angeles Capital in 2002. Mr. Reynolds oversees Los Angeles Capital's investment process and works closely with Los Angeles Capital's research team to enhance elements of the stock selection, portfolio construction and trading processes. He has worked in investment management since 1982 and has managed investment portfolios since 1998.

Daniel Arche, CFA, Director, Portfolio Strategy and Senior Portfolio Manager, joined Los Angeles Capital in 2007. Mr. Arche is responsible for managing accounts in accordance with Los Angeles Capital's investment philosophy and process. Mr. Arche works to ensure that portfolios reflect the investment outlook of Los Angeles Capital's Dynamic Alpha Stock Selection Model​® (Model) and that portfolios are operating within expected risk tolerances and guidelines. He recommends changes to portfolio parameters with the goal of enhancing returns or better controlling risk. Mr. Arche is a member of Los Angeles Capital's Investment Committee and chairs the Portfolio Review Committee that reviews the performance, risk profile and characteristics of client portfolios and the outlook of the Model.

Daniel E. Allen, CFA, Chief Executive Officer and President, joined Los Angeles Capital in 2009. Mr. Allen is responsible for implementing Los Angeles Capital's mission, vision and business strategies across the organization. Mr. Allen is a senior member of the Portfolio Management team and a member of the firm's Investment Committee. He has worked in investment management since 1983 and has worked with equity management, private markets, asset management and in consulting.

Optimum Large Cap Value Fund

Massachusetts Financial Services Company (MFS ​®), located at 111 Huntington Avenue, Boston, MA 02199, is America's oldest mutual fund organization. MFS and its predecessor organizations have a history of money management dating from 1924 and the founding of the first mutual fund. As of March 31, 2025, net assets under the management of the MFS organization were approximately $602 billion. MFS has held its Fund responsibilities since the Fund's inception.

Nevin Chitkara, Investment Officer of MFS, Katherine Cannan, Investment Officer of MFS, and Thomas Crowley, Investment Officer of MFS, have primary responsibility for the day-to-day portfolio management of MFS' share of the Fund's assets. Mr. Chitkara, Ms. Cannan and Mr. Crowley have been employed in the investment area of MFS since 1997, 2013 and 2007, respectively. Mr. Chitkara, Ms. Cannan and Mr. Crowley have held their Fund responsibilities since May 2006, December 2019 and December 2024, respectively. Mr. Chitkara has announced his intention to retire effective May 1, 2026, and he will no longer be a portfolio manager of the Fund as of that date.

Great Lakes Advisors, LLC (Great Lakes), with offices in Chicago, IL, Stamford, CT and Tampa, FL, offers customized investment advisory and sub-advisory services on a discretionary and non-discretionary basis to a broad range of clients including high net worth individuals, sub-advised accounts, private funds, sub-advised mutual funds and collective investment trusts, institutions, pension, profit sharing and retirement plans of endowments, foundations, religious institutes, multi-employer, charitable organizations, healthcare and governmental entities. Great Lakes also provides non-discretionary investment advice via model delivery to various wrap account programs. Great Lakes is an SEC-registered investment advisor that was established in 1981. In 2011, Great Lakes became a wholly owned subsidiary of Wintrust Financial Corporation, a publicly traded financial services company (NASDAQ: WTFC), as a stand-alone investment manager. As of March 31, 2025, Great Lakes had approximately $17.91 billion in assets under management and advisement. Great Lakes has held its Fund responsibilities since April 2023.

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Paul Roukis and Jeff Agne share primary responsibility for the day-to-day portfolio management of Great Lake's share of the Fund's assets. They are assisted by other members of Great Lakes' large-cap investment team. Mr. Roukis is a Portfolio Manager at Great Lakes and was employed by the predecessor firm Rothschild & Co since 2005, previously serving as a Managing Director. Mr. Agne is a Portfolio Manager at Great Lakes and was employed by the predecessor firm Rothschild & Co since 2015, previously serving as a Managing Director. Messrs. Roukis and Agne have held their Fund responsibilities since October 2016 and April 2020, respectively.

Optimum Small-Mid Cap Growth Fund

Principal Global Investors, LLC (Principal) has its primary office location is 711 High Street, Des Moines, IA 50392. Prior to July 2022, Principal was formerly the Small-Mid Growth team of Columbus Circle Investors (CCI). Principal is an investment advisor and wholly-owned subsidiary of the publicly traded Principal Financial Group, Inc. (NASDAQ: PFG). As of March 31, 2025, the team had approximately $555.8 billion in assets under management. Principal (formerly CCI) has held its Fund responsibilities since April 2016.

A team of portfolio managers is primarily responsible for the day-to-day management of Principal's allocated portion of the Fund's assets. Principal's portfolio management team of Christopher Corbett, CFA and Marc Shapiro are jointly and primarily responsible for day-to-day management of all Principal accounts. Mr. Corbett, CFA, joined the firm in 2006 and currently serves as Sr. Managing Director and lead Portfolio Manager for SMID Cap Growth, Mid Cap Growth and Small Cap Growth strategies. Mr. Corbett began holding Fund responsibilities in July 2017. Mr. Shapiro joined the firm in 2004 and serves as Managing Director, Portfolio Manager for the SMID Cap Growth, Mid Cap Growth and Small Cap Growth strategies. Mr. Shapiro began holding Fund responsibilities in July 2020.

Peregrine Capital Management, LLC (Peregrine) is an investment advisor located at 800 LaSalle Avenue, Suite 1750, Minneapolis, MN 55402. Peregrine was founded in 1984 and predominantly serves the institutional marketplace through separately managed portfolios in addition to providing sub-advisory services for mutual funds and Commingled Investment Trusts. As of March 31, 2025, Peregrine had approximately $4.1 billion in assets under management. Assets in Peregrine's Small Cap Growth style for the same period were $1.6 billion. Peregrine has held its Fund responsibilities since April 2016.

A team of portfolio managers is primarily responsible for the day-to-day management of Peregrine's share of the Fund's assets. Peregrine's portfolio management team of Paul von Kuster, CFA; Samuel Smith, CFA; Ryan Smith, CFA; and Allison Lewis, CFA, are jointly and primarily responsible for day-to-day management of Peregrine's accounts. Mr. von Kuster is a Portfolio Manager for the Small Cap Growth style and shares the responsibility for fundamental research, stock selection and portfolio management with his team. He has been with the firm since its inception in 1984. Prior to Peregrine, Mr. von Kuster managed small cap funds for the Trust Department at Norwest Bank Minnesota, N.A. (now Wells Fargo Bank Minnesota, N.A.). He began his career with Norwest Bank Minnesota, N.A. in 1972 after graduating from Princeton. Mr. von Kuster is a member of the CFA Society of Minnesota and the CFA Institute. Mr. S. Smith is a Portfolio Manager for the Small Cap Growth style and shares the responsibility for fundamental research, stock selection and portfolio management with his team. Mr. S. Smith joined Peregrine in 2006 as a Portfolio Assistant and has also served as an Analyst and Associate Portfolio Manager. He graduated from the University of St. Thomas. Mr. Smith is a member of the CFA Society of Minnesota and the CFA Institute. Mr. R. Smith joined Peregrine in 2018 as an Associate Portfolio Manager. Prior to joining Peregrine, Mr. R. Smith was a Portfolio Manager and an Analyst on the Small, SMID and Mid Cap Growth strategies at RBC Global Asset Management (U.S.) for more than 10 years. He graduated from Lehigh University and received his M.S. in Accountancy from the University of Notre Dame. Mr. R. Smith is a member of the CFA Society of Minnesota and the CFA Institute. Ms. Lewis shares the responsibility for fundamental research, stock selection and portfolio management with her team. Ms. Lewis joined Peregrine in 2022 as a Senior Analyst. Prior to joining Peregrine, Ms. Lewis was a Research Analyst at Marsico Capital Management for two years. Previously, she served as Senior Equity Analyst at Invesco for over six years. She started her career at J.P. Morgan Chase & Company. Ms. Lewis graduated from the University of Michigan and earned her M.B.A. from the University of Wisconsin. She is a member of the CFA Institute. Mr. von Kuster has held his Fund responsibilities since April 2016. Mr. S. Smith and Mr. R. Smith have held their Fund responsibilities as portfolio managers since January 2021 and Ms. Lewis has held her Fund responsibilities as a portfolio manager since July 2023.

Optimum Small-Mid Cap Value Fund

LSV Asset Management (LSV) is an investment advisor located at 155 North Wacker Drive, Suite 4600 in Chicago, IL. LSV was founded in 1994 and provides domestic, international and global value equity investment management to institutional investors. As of March 31, 2025, LSV had approximately $92 billion in assets under management. LSV has held its Fund responsibilities since January 2016.

A team of portfolio managers is primarily responsible for the day-to-day management of LSV's share of the Fund's assets. LSV's portfolio management team of Josef Lakonishok, Ph.D; Menno Vermeulen, CFA; Puneet Mansharamani, CFA; Greg Sleight; Guy Lakonishok, CFA; and Gal Skarishevsky are jointly and primarily responsible for day-to-day management of LSV's accounts. Dr. Lakonishok has served as CEO, CIO, Partner and Portfolio Manager for LSV since its founding in 1994. Mr. Vermeulen, CFA, has served as a Portfolio Manager for LSV since 1995 and a Partner since 1998. Prior to joining LSV, he worked at ABP where he was responsible for the development and implementation of quantitative active investment strategies. Mr.

39

Who manages the Funds

Mansharamani, CFA, has served as a Partner and Portfolio Manager for LSV since 2006. Prior to joining LSV, Mr. Mansharamani was an Analyst at Institutional Trust National City Corporation. Prior to this experience, Mr. Mansharamani was a Systems Consultant for Maximations, Inc. Mr. Sleight has served as a Quantitative Analyst of LSV since 2006, a Partner since 2012 and Portfolio Manager since 2014 and is part of LSV's quantitative and implementation team, which is responsible for the day-to-day data management, portfolio implementation and ongoing enhancement of LSV's model and systems. Mr. G. Lakonishok, CFA has served as a Quantitative Analyst of LSV since 2009, a Partner since 2013 and Portfolio Manager since 2014. Prior to joining LSV, Mr. Lakonishok was a Vice President in the Quantitative Equity group at BlackRock. Mr. Skarishevsky has served as a Quantitative Analyst of LSV since 2017, a Partner since 2022 and Portfolio Manager since 2025, and has more than 8 years of investment experience. Dr. J. Lakonishok, Mr. Vermeulen, Mr. Mansharamani, Mr. Sleight, and Mr. G. Lakonishok have all held their Fund responsibilities since January 2016 and Mr. Skarishevsky since March 2025.

Wellington Management Company LLP (Wellington) is an investment adviser located at 280 Congress Street, Boston, MA 02210. Tracing its roots to the founding of the Wellington Fund in 1928, the original Wellington Management Company was incorporated in 1933. The current Wellington Management Company LLP was established in 2014 and succeeded to the registration of the original firm on January 1, 2015. Wellington's experience as investment manager of mutual funds and other relationships with third-party distributors began with the inception of the Wellington Fund in 1928 and has grown since then to include 441 subadvised portfolios with clients around the globe, totaling over $1.2 trillion in assets under management as of March 31, 2025. Wellington has held its Fund responsibilities since June 2024.

Gregory J. Garabedian has primary responsibility for the day-to-day portfolio management of Wellington's share of the Fund's assets. He is assisted by other members of Wellington's SMID Opportunistic Value investment team. Mr. Garabedian is a Partner of Wellington and is an equity portfolio manager on the Opportunistic Value team. He manages equity assets on behalf of our clients, drawing on research from Wellington's global industry analysts, equity portfolio managers, and team analysts. He currently manages a suite of smid cap and midcap value approaches, and works in our Radnor, Pennsylvania office. Prior to joining Wellington in 2006, Greg worked as an equity research analyst at Gabelli and Company (2005 - 2006). Before that, he worked as a forensic accountant at PricewaterhouseCoopers (1997 - 2003). Greg earned his MBA in finance from the University of Pennsylvania (Wharton, 2005) and his BS in accounting from Villanova University (1997). Mr. Garabedian has held his Fund responsibilities since June 2024.

Optimum International Fund

Baillie Gifford Overseas Limited (Baillie Gifford), located at Calton Square, 1 Greenside Row, Edinburgh EH1 3AN, UK, is a wholly owned subsidiary of Baillie Gifford & Co. Baillie Gifford was founded in 1983 and provides investment management and advisory services to non-UK clients. As of March 31, 2025, Baillie Gifford had approximately $254 billion in assets under management. Baillie Gifford has held its Fund responsibilities since April 2021.

A team of portfolio managers is primarily responsible for the day-to-day management of Baillie Gifford's share of the Fund's assets. Donald Farquharson, Jenny Davis, Tom Walsh, Chris Davies, Steve Vaughan and Roderick Snell are jointly and primarily responsible for day-to-day management of Baillie Gifford accounts. Mr. Farquharson, Ms. Davis and Mr. Walsh have all held their Fund responsibilities since April 2021. Mr. Davies has held his Fund responsibilities since September 2021. Mr. Vaughan has held his Fund responsibilities since September 2022. Mr. Snell has held his Fund responsibilities since March 2024.

Mr. Farquharson heads the Japanese Equities Team and has been a member of the International Alpha Portfolio Construction Group (PCG) since 2014. He joined Baillie Gifford in 2008 and became a Partner in 2017. He has 37 years' investment experience dedicated almost entirely to Japanese Equities. Donald spent 20 years working for Schroders as a Japanese specialist, latterly as Head of the Pan Pacific Equity Team. Between 1991 and 1995, he headed Schroders' Research Team in Tokyo. Mr. Farquharson graduated MA (Hons) in Arabic Studies from the University of St Andrews in 1987 and is a CFA Charterholder.

Ms. Davis conducts research for International Alpha portfolios and has been a member of the International Alpha Portfolio Construction Group (PCG) since 2016. She joined Baillie Gifford in 2011 and became a partner in 2022. Jenny worked on two of our global equity strategies, having started her career at Neptune Investment Management. Ms. Davis graduated MA in Music from the University of Oxford in 2008, and latterly undertook postgraduate studies in Psychotherapy at the University of Edinburgh.

Mr. Walsh conducts research for International Alpha portfolios and has been a member of the International Alpha Portfolio Construction Group (PCG) since 2018. He joined Baillie Gifford in 2009, and became a partner in 2022. He has worked on the UK, European and Global Opportunities teams, as well as spending four years as a member of the International Focus PCG. Before joining Baillie Gifford, Tom worked at Fidelity International, Merrill Lynch and Deloitte & Touche. He graduated LLB (Hons) in Law & Economics from the University of Edinburgh in 1999 and is both CFA and ACA qualified.

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Mr. Davies conducts research for International Alpha portfolios and has been a member of the International Alpha Portfolio Construction Group (PCG) since 2021. He joined Baillie Gifford in 2012, and most recently served as an Investment Manager in the European Team. Chris graduated BA (Hons) in Music from the University of Oxford in 2009 and went on to gain an MMus in Music Performance from the Royal Welsh School of Music and Drama in 2010 and an MSc in Music, Mind and Brain from Goldsmiths College in 2011.

Mr. Vaughan became a member of the International Alpha Portfolio Construction Group in September 2022. Steve joined Baillie Gifford in 2012 and has been an Investment Manager in the Smaller Companies Team. Prior to joining Baillie Gifford, Steve was an Officer in the British Army for nine years. He is a CFA Charterholder. He graduated BA (Hons) in Jurisprudence from the University of Oxford in 2001 and MA in International Relations from the University of Exeter in 2012.

Mr. Snell became a member of the International Alpha Portfolio Construction Group in March 2024. Roderick is also an investment manager in the Emerging Markets Equity Team. He joined Baillie Gifford in 2006 and became a partner of the firm in 2023. He has managed the Baillie Gifford Pacific Fund since 2010 and the Pacific Horizon Investment Trust since 2021 (having been deputy since 2013). He has also co-managed the China Growth Trust for several years. Prior to joining the Emerging Markets Equity team in 2008, he also spent time in the UK and European equity teams. Roderick graduated BSc (Hons) in Medical Biology from the University of Edinburgh in 2006.

Acadian Asset Management LLC (Acadian), located at 260 Franklin Street, Boston, MA 02110, is a subsidiary of Acadian Affiliate Holdings LLC, which is an indirectly wholly owned subsidiary of Acadian Asset Management Inc. (“AAMI”), a publicly listed company on the NYSE. Acadian has been managing assets since 1987. As of March 31, 2025, Acadian managed approximately $121.86 billion in assets. Acadian has held its Fund responsibilities since January 2015.

Brendan O. Bradley, Ph.D., is Executive Vice President and Chief Investment Officer at Acadian. Dr. Bradley joined Acadian in 2004 and is the chief investment officer. Brendan has served as the firm's director of portfolio management, overseeing portfolio management policy, and was also previously the director of Acadian's Managed Volatility strategies. He is a member of the Acadian Board of Managers and Executive Management Team. Prior to Acadian, Brendan was a vice president at Upstream Technologies, where he designed and implemented investment management systems and strategies. His professional background also includes work as a research analyst and consultant at Samuelson Portfolio Strategies. Brendan earned a Ph.D. in applied mathematics from Boston University and a B.A. in physics from Boston College. Brendan has held his Fund responsibilities since January 2015.

Fanesca Young, Ph.D., serves as Senior Vice President, Director, Equity Portfolio Management at Acadian. She is a member of the firm's Senior Investment Leadership Team and helps to oversee and direct investment and research processes used by Acadian and the individuals that implement those processes. Prior to joining Acadian, she led the Global Systematic Equities team at GIC and is responsible for the management of long-only, active extension, and absolute return equity strategies. Prior to joining GIC, she was a Principal at Los Angeles Capital Management and served as Managing Director and Director of Quantitative Research, where she oversaw the firm's proprietary stock selection model and supervised the execution of technical methodologies in the firm's strategies. Fanesca has served on several editorial boards, including the Financial Analyst Journal and the Journal of Systematic Investing, and has published applied research in industry journals. Fanesca earned a Ph.D. in statistics from Columbia University and an M.Phil. and an M.A. in statistics from Columbia University. She also holds a B.A. in mathematics from the University of Virginia. Fanesca is a CFA charterholder. Fanesca has held her Fund responsibilities since July 2024.

Optimum Fixed Income Fund

Janaki Rao and Andrew Vonthethoff are primarily responsible for the day-to-day management of the Manager's share of the Fund's assets. When making decisions for the Fund, Messrs. Rao and Vonthethoff regularly consult with other investment professionals.

Janaki Rao is a Managing Director and Head of the US Multisector Team within Macquarie Asset Management (MAM) Credit, a role he assumed in May 2024. He has overall responsibility for MAM Credit's US multisector capabilities, including the portfolios, the team, and client and business management. Prior to joining Macquarie, he was Director of US Multisector Fixed Income at AllianceBernstein from November 2019 to February 2023, responsible for managing multisector fixed income portfolios, including Treasury inflation-protected securities (TIPS) and agency mortgage-backed securities (MBS) portfolios. Before that, he was AllianceBernstein's Head of Agency MBS from March 2013 to November 2019, and prior to that spent seven years at Morgan Stanley as Vice President of Agency MBS Research. Janaki received a Bachelor of Arts (Honors) in economics from the University of Delhi, a Master of Business Administration with an emphasis in marketing from Symbiosis Institute of Business Management, and a Master of Business Administration with an emphasis in finance from the Zicklin School of Business at Baruch College.

Andrew Vonthethoff is a Senior Portfolio Manager for the Global Fixed Income Team within Macquarie Asset Management (MAM) Credit. He is a lead portfolio manager for global multisector and global bond strategies, a role he assumed in June 2013, and for US multisector portfolios, which he assumed in May 2024. In this role, he is responsible for asset allocation, sector rotation, and security selection across MAM Credit's global and US multisector portfolios. Andrew joined the firm in 2008 as a Quantitative Analyst on MAM Credit's Markets and Quantitative Team, where he was involved in building and

41

Who manages the Funds

maintaining financial models. He transferred to the Global Fixed Income Team in 2010, becoming an Assistant Portfolio Manager. He earned a Bachelor of Commerce in actuarial studies and finance from the University of New South Wales. He also holds the Chartered Financial Analyst​® designation.

Pacific Investment Management Company LLC (PIMCO), located at 650 Newport Drive, Newport Beach CA 92660, was founded in 1971. PIMCO managed $2.02 trillion in assets, including $1.64 trillion in third-party client assets as of March 31, 2025. Assets include $75.4 billion (as of December 31, 2024) managed by PIMCO Prime Real Estate (formerly Allianz Real Estate), an affiliate and wholly-owned subsidiary of PIMCO and PIMCO Europe GmbH.

Marc P. Seidner, Mike Cudzil and Mohit Mittal are primarily responsible for the day-to-day management of PIMCO's share of the Fund's assets. In addition, PIMCO has an Investment Committee, which oversees the setting of investment policy decisions, including duration positioning, yield curve management, sector rotation, credit quality and overall portfolio composition, for all PIMCO portfolios and strategies, including PIMCO's share of the Fund's assets.

Mr. Seidner is CIO Non-traditional Strategies and a managing director in the Newport Beach office. He is also a generalist portfolio manager and a member of the Investment Committee. He rejoined PIMCO in November 2014 after serving as head of fixed income at GMO LLC, and previously he was a PIMCO managing director, generalist portfolio manager and member of the Investment Committee until January 2014. Prior to joining PIMCO in 2009, he was a managing director and domestic fixed income portfolio manager at Harvard Management Company. Previously, he was director of active core strategies at Standish Mellon Asset Management and a senior portfolio manager at Fidelity Management and Research. He has 38 years of investment experience and holds an undergraduate degree in economics from Boston College. He has held his Fund responsibilities since January 2015.

Mr. Cudzil is a managing director and generalist portfolio manager based in the Newport Beach office. He is a rotating member of the PIMCO Investment Committee and co-chair of the Americas Portfolio Committee. As a portfolio manager across multi-sector fixed income mandates, Mr. Cudzil serves as co-lead of the liability-driven investment (LDI) portfolio management team, a senior member of the Total Return portfolio management team, and lead of the U.S. inflation portfolio management team. Prior to joining PIMCO in 2012, he worked as a managing director and head of pass-through trading at Nomura. He previously held similar roles at Bank of America and Lehman Brothers, as well as a senior trading position at Salomon Brothers. He has 28 years of investment experience and holds a bachelor's degree in political science from the University of Pennsylvania. He has held his Fund responsibilities since July 2023.

Mr. Mittal is CIO Core Strategies and a managing director based in the Newport Beach office. He is a member of the Investment Committee and a portfolio manager for fixed income multi-sector portfolios across the duration and credit spectrum. As CIO Core Strategies, Mr. Mittal has leadership and oversight responsibilities for long-only strategies across PIMCO's Low and Moderate Duration, Total Return, and Long Duration strategy suite. Morningstar named him winner of the 2020 U.S. Morningstar Award for Investing Excellence in the Rising Talent category. Mr. Mittal also serves on the board of Orangewood Foundation. He joined PIMCO in 2007 and holds an MBA from the Wharton School of the University of Pennsylvania and an undergraduate degree in computer science from Indian Institute of Technology (IIT) in Delhi, India. He has held his Fund responsibilities since July 2023.

Macquarie Investment Management Austria Kapitalanlage AG (MIMAK), located at Kaerntner Strasse 28, 1010 Vienna, Austria, is an affiliate of the Manager and a part of MAM. Although the Manager has principal responsibility for the Manager's portion of the Fund, the Manager may seek investment advice and recommendations from MIMAK and the Manager may also permit MIMAK to execute Fund security trades on behalf of the Manager and exercise investment discretion for securities in certain markets where the Manager believes it will be beneficial to utilize MIMAK's specialized market knowledge.

Macquarie Investment Management Europe Limited (MIMEL), located at 28 Ropemaker Street, London, England, is an affiliate of the Manager and a part of MAM. Although the Manager has principal responsibility for the Manager's portion of the Fund, the Manager may seek investment advice and recommendations from MIMEL and the Manager may also permit MIMEL to execute Fund security trades on behalf of the Manager and exercise investment discretion for securities in certain markets where the Manager believes it will be beneficial to utilize MIMEL's specialized market knowledge.

Macquarie Investment Management Global Limited (MIMGL), located at 1 Elizabeth Street, Sydney NSW 2000, Australia, is an affiliate of the Manager and a part of MAM. Although the Manager has principal responsibility for the Manager's portion of the Fund, the Manager may seek investment advice and recommendations from MIMGL and the Manager may also permit MIMGL to execute Fund security trades on behalf of the Manager and exercise investment discretion for securities in certain markets where the Manager believes it will be beneficial to utilize MIMGL's specialized market knowledge.

The SAI provides additional information about each portfolio manager's compensation, other accounts managed by each portfolio manager, and each portfolio manager's ownership of Fund shares.

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Manager of managers structure

The Funds and the Manager have received an exemptive order from the SEC to operate under a manager of managers structure that permits the Manager, with the approval of the Funds' Board, to appoint and replace both affiliated and unaffiliated sub-advisors, and to enter into and make material amendments to the related sub-advisory contracts on behalf of the Funds without shareholder approval (Manager of Managers Structure). Under the Manager of Managers Structure, the Manager has ultimate responsibility, subject to oversight by the Board, for overseeing the Funds' sub-advisors and recommending to the Board their hiring, termination, or replacement.

The Manager of Managers Structure enables the Funds to operate with greater efficiency and without incurring the expense and delays associated with obtaining shareholder approvals for matters relating to sub-advisors or sub-advisory agreements. The Manager of Managers Structure does not permit an increase in the overall management and advisory fees payable by the Funds without shareholder approval. Shareholders will be notified of the hiring of any new sub-advisor within 90 days of the hiring.

The Funds and the Manager also have an exemptive order from the SEC that allows the approval of a new sub-advisor to be taken at a Board of Trustees meeting held via any means of communication that allows the Trustees to hear each other simultaneously during the meeting.

Who's who

Board of trustees: A mutual fund is governed by a board of trustees, which has oversight responsibility for the management of the fund's business affairs. Trustees establish procedures and oversee and review the performance of the fund's service providers.

Investment manager and sub-advisor: An investment manager is a company with overall responsibility for the management of a fund's assets. A sub-advisor is a company generally responsible for the day-to-day management of the fund's assets or some portion thereof. The sub-advisor is selected and supervised by the investment manager. The investment manager or the sub-advisor, as the case may be, is responsible for selecting portfolio investments consistent with the objective and policies stated in the mutual fund's prospectus. A written contract between a mutual fund and its investment manager specifies the services the investment manager performs and the fee the manager is entitled to receive.

Portfolio managers: Portfolio managers make investment decisions for individual portfolios.

Distributor: Most mutual funds continuously offer new shares to the public through distributors that are regulated as broker/dealers and are subject to the Financial Industry Regulatory Authority (FINRA) rules governing mutual fund sales practices.

Service agent: Mutual fund companies employ service agents (sometimes called transfer agents) to maintain records of shareholder accounts, calculate and disburse dividends and capital gains, and prepare and mail shareholder statements and tax information, among other functions. Many service agents also provide administrative services to a fund and oversight of other fund service providers.

Custodian/Fund accountant: Mutual funds are legally required to protect their portfolio securities, and most funds place them with a qualified bank custodian that segregates fund securities from other bank assets. The fund accountant provides services such as calculating a fund's net asset value (NAV) and providing financial reporting information for the fund.

Financial intermediary: Financial professionals provide advice to their clients. They are associated with securities broker/dealers who have entered into selling and/or service arrangements with the distributor. Selling broker/dealers and financial professionals are compensated for their services generally through sales commissions, and through 12b-1 fees and/or service fees deducted from a fund's assets.

Shareholders: Mutual fund shareholders have specific voting rights on matters such as material changes in the terms of a fund's management contract and changes to fundamental investment policies.

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About your account

Investing in the Funds

Shares of the Funds may be purchased only through a participating securities dealer or other financial intermediary.

You can choose from a number of share classes for each Fund. Because each share class has a different combination of sales charges, fees, and other features, you should consult your participating securities dealer or other financial intermediary (hereinafter collectively referred to as the “financial intermediary”) to determine which share class best suits your investment goals and time frame. It is the responsibility of your financial intermediary to assist you in determining the most appropriate share class and to communicate such determination to us.

Information about existing sales charges and sales charge reductions and waivers is available in this Prospectus below and free of charge on the Optimum Funds website at optimummutualfunds.com. Additional information on sales charges can be found in the SAI, which is available upon request.

Certain financial intermediaries may charge you additional fees in connection with transactions in Fund shares. Shareholders purchasing Fund shares through a financial intermediary may also be eligible for sales charge discounts or waivers which may differ from those disclosed elsewhere in this Prospectus or SAl. The availability of certain initial or deferred sales charge waivers and discounts may depend on the particular financial intermediary or type of account through which you purchase or hold Fund shares. It is the responsibility of the financial intermediary to implement any of their proprietary sales charge discounts or waivers. Accordingly, you should consult with your financial intermediary to determine whether you qualify for any sales charge discounts or waivers.

Choosing a share class

Class A and Class C shares may be eligible for purchase through programs sponsored by financial intermediaries that require the purchase of a specific class of shares.

Class A and Class C shares have each adopted a separate 12b-1 plan that allows them to pay service fees for providing services to shareholders of that class and/or maintaining shareholder accounts for that class, and distribution fees for the sale and distribution of shares of the class. Because these fees are paid out of class assets on an ongoing basis, over time these fees will increase the cost of your investment and may cost you more than paying other types of sales charges.

Class A sales charges

The table below details your sales charges on purchases of Class A shares. The offering price for Class A shares includes the front-end sales charge. The offering price is determined by dividing the NAV per share by an amount equal to 1 minus the sales charge (expressed in decimals) applicable to the purchase, calculated to two decimal places using standard rounding criteria. The sales charge as a percentage of the net amount invested is the maximum percentage of the amount invested rounded to the nearest hundredth. The actual sales charge that you pay as a percentage of the offering price and as a percentage of the net amount invested will vary depending on the then-current NAV, the percentage rate of the sales charge, and rounding. The number of Fund shares you will be issued will equal the amount invested divided by the applicable offering price for those shares, calculated to three decimal places using standard rounding criteria. Sales charges do not apply to shares purchased through dividend reinvestment.