SUPPLEMENT TO CURRENT PROSPECTUS OF KEYSTONE CUSTODIAN FUND, SERIES S-4 The section of the Fund's prospectus entitled "Fund Management and Expenses; Portfolio Manager" is hereby supplemented to reflect the following (to be inserted in place of the text thereunder): "Christopher R. Ely has recently become the Fund's Portfolio Manager. He is a Keystone Vice President and Senior Portfolio Manager and has more than 15 years' experience in equity investing." March 2, 1995

- -------------------------------------------------------------------------------- KEYSTONE [Photograph] S-4 SMALL COMPANY GROWTH FUND - -------------------------------------------------------------------------------- [Logo] PROSPECTUS AND APPLICATION

- -------------------------------------------------------------------------------- PROSPECTUS SEPTEMBER 30, 1994 - -------------------------------------------------------------------------------- KEYSTONE CUSTODIAN FUND, SERIES S-4 SMALL COMPANY GROWTH FUND 200 Berkeley Street, Boston, Massachusetts 02116-5034 Call toll free 1-800-343-2898 Keystone Custodian Fund, Series S-4 (the "Fund") is a mutual fund whose goal is long-term growth of capital. Income is not an objective. The Fund invests principally in common stocks, which are expected to experience wide fluctuations in price in both rising and declining markets. Your purchase payment is fully invested. There is no sales charge when you buy the Fund's shares. The Fund may impose a deferred sales charge, which declines from 4% to 1%, if you redeem your shares within four years of purchase. The Fund has adopted a Distribution Plan (the "Distribution Plan") pursuant to Rule 12b-1 under the Investment Company Act of 1940 (the "1940 Act")under which it bears some of the costs of selling its shares to the public. This prospectus sets forth concisely the information about the Fund that you should know before investing. Please read it and retain it for future reference. Additional information about the Fund is contained in a statement of additional information dated September 30, 1994, which has been filed with the Securities and Exchange Commission and is incorporated by reference into this prospectus. For a free copy, or for other information about the Fund, write to the address or call the telephone number listed above. SHARES OF THE FUND ARE NOT DEPOSITS OR OBLIGATIONS OF, OR GUARANTEED OR ENDORSED BY, ANY BANK, AND SHARES ARE NOT FEDERALLY INSURED BY THE FEDERAL DEPOSIT INSURANCE CORPORATION, THE FEDERAL RESERVE BOARD, OR ANY OTHER AGENCY. - -------------------------------------------------------------------------------- TABLE OF CONTENTS - -------------------------------------------------------------------------------- Page Fee Table ................................................................. 2 Financial Highlights ...................................................... 3 Fund Description .......................................................... 4 Fund Objective and Policies ............................................... 4 Investment Restrictions ................................................... 5 Pricing Shares ............................................................ 5 Dividends and Taxes ....................................................... 6 Fund Management and Expenses .............................................. 7 How to Buy Shares ......................................................... 8 Distribution Plan ......................................................... 9 How to Redeem Shares ...................................................... 11 Shareholder Services ...................................................... 13 Performance Data .......................................................... 14 Fund Shares ............................................................... 14 Additional Information .................................................... 14 Additional Investment Information ......................................... (i) - -------------------------------------------------------------------------------- THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE SECURITIES AND EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION NOR HAS THE SECURITIES AND EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE. - --------------------------------------------------------------------------------

FEE TABLE Keystone Custodian Fund, Series S-4 Small Company Growth Fund The purpose of the fee table is to assist investors in understanding the costs and expenses that an investor in the Fund will bear, either directly or indirectly. For more complete descriptions of the various costs and expenses, see the following sections of this prospectus: "Fund Management and Expenses"; "How to Buy Shares"; "Distribution Plan"; and "Shareholder Services." Shareholder Transaction Expenses Contingent Deferred Sales Charge(1) ........................ 4.00% (as a percentage of the lesser of total cost or the net asset value of shares redeemed) Exchange Fee(2) ............................................ $10.00 (per exchange) Annual Fund Operating Expenses(3) (as a percentage of average net assets) Management Fees ............................................ 0.52% 12b-1 Fees(4) .............................................. 0.93% Other Expenses ............................................. 0.28% ---- Total Fund Operating Expenses .............................. 1.73% ==== 1 Year 3 Years 5 Years 10 Years ------ ------- ------- -------- Example(5) You would pay the following expenses on a $1,000 investment, assuming (1) 5% annual return and (2) redemption at the end of each period: ................. $58.00 $74.00 $94.00 $204.00 You would pay the following expenses on the same investment, assuming no redemption: ......................... $18.00 $54.00 $94.00 $204.00 AMOUNTS SHOWN IN THE EXAMPLE SHOULD NOT BE CONSIDERED A REPRESENTATION OF PAST OR FUTURE EXPENSES; ACTUAL EXPENSES MAY BE GREATER OR LESS THAN THOSE SHOWN. - ---------- (1) The deferred sales charge declines from 4% to 1% of amounts redeemed within four calendar years after purchase. No deferred sales charge is imposed thereafter. (2) There is no exchange fee for exchange orders received by the Fund directly from a shareholder over the Keystone Automated Response Line("KARL"). (For a description of KARL, see "Shareholder Services.") (3) Expense ratios are for the Fund's fiscal year ended May 31, 1994. (4) The 12b-1 fee represents, on a financial statement basis, the net percentage attributable to 12b-1 expenses for the fiscal year ended May 31,1994, after deduction from gross 12b-1 expenses of deferred sales charges recovered during such period. Long-term shareholders may pay more than the economic equivalent of the maximum front-end sales charges permitted by rules adopted by the National Association of Securities Dealers, Inc. ("NASD"). In accordance with NASD rules, the Fund has limited its annual 12b-1 expenses to 1.00% of average net assets. (5) The Securities and Exchange Commission requires use of a 5% annual return figure for purposes of this example. Actual return for the Fund may be greater or less than 5%. 2

FINANCIAL HIGHLIGHTS KEYSTONE CUSTODIAN FUND, SERIES S-4 -- SMALL COMPANY GROWTH FUND (For a share outstanding throughout the year) The following table contains significant financial information with respect to the Fund and has been audited by KPMG Peat Marwick LLP, the Fund's independent auditors. The table has been taken from the Fund's Annual Report and should be read in conjunction with the Fund's financial statements and related notes, which also appear, together with the auditors' report, in the Fund's Annual Report. The Fund's financial statements, related notes, and auditors' report are included in the statement of additional information. Additional Information about the Fund's performance is contained in its Annual Report, which will be made available upon request and without charge. <TABLE> <CAPTION> Year Ended May 31, ------------------------------------------------------------------------------------ 1994<F1> 1993<F1> 1992<F1> 1991<F1> 1990<F1> 1989<F1> ------- ------- ------- ------- ------- ------- <S> <C> <C> <C> <C> <C> <C> Net Asset Value, Beginning of Year ......... $ 7.95 $ 7.61 $ 7.17 $ 6.24 $ 5.66 $ 4.48 Income From Investment Operations Investment Income (Deficit) -- Net ......... (0.12) (0.12) (0.08) (0.04) -0- 0.02 Realized Gains (Losses) on Investments ..... 0.63 1.82 0.98 1.17 0.63 1.20 Net Commissions Paid on Fund Share Sales <F2> -0- -0- -0- -0- -0- -0- ------- ------- ------- ------- ------- ------- Total from Investment Operations ........... 0.51 1.70 0.90 1.13 0.63 1.22 ------- ------- ------- ------- ------- ------- Less Distributions <F5> Distributions from Net Investment Income ... -0- -0- -0- -0- (0.05) (0.01) Distributions from capital gains ........... (0.82) (1.36) (0.46) (0.20) -0- (0.03) ------- ------- ------- ------- ------- ------- Total Distributions ........................ (0.82) (1.36) (0.46) (0.20) (0.05) (0.04) ------- ------- ------- ------- ------- ------- Net Asset Value, End of Year ............... $ 7.64 $ 7.95 $ 7.61 $ 7.17 $ 6.24 $ 5.66 ======= ======= ======= ======= ======= ======= Total Return <F4> ........................... 6.84% 28.76% 13.45% 19.42% 11.24% 27.45% Ratios/Supplemental Data Ratios to Average Net Assets: Operating and Management Expenses .......... 1.73% 2.04% 1.47% 1.48% 1.40% 1.27% Investment Income (Deficit) -- Net ......... (1.49%) (1.68%) (1.09%) (0.68%) 0.02% 0.47% Portfolio Turnover Rate<F3> ................. 60% 78% 81% 73% 77% 57% Net Assets, End of Year (thousands) ........ $1,005,595 $965,959 $702,442 $623,291 $537,912 $503,908 </TABLE> <TABLE> <CAPTION> Year Ended May 31, ----------------------------------------------------- 1988 1987 1986 1985 -------- ------- ------- ------- <S> <C> <C> <C> <C> Net Asset Value, Beginning of Year ......... $ 7.80 $ 7.60 $ 5.78 $ 5.47 Income From Investment Operations Investment Income (Deficit) -- Net ......... -0- -0- -0- 0.03 Realized Gains (Losses) on Investments ..... (1.64) 1.11 1.86 0.93 Net Commissions Paid on Fund Share Sales <F2> -0- (0.02) (0.02) (0.02) -------- ------- ------- ------- Total from Investment Operations ........... (1.64) 1.09 1.84 0.94 -------- ------- ------- ------- Less Distributions <F5> Distributions from Net Investment Income ... -0- (0.01) (0.02) (0.02) Distributions from capital gains ........... (1.68) (0.88) -0- (0.61) -------- ------- ------- ------- Total Distributions ........................ (1.68) (0.89) (0.02) (0.63) -------- ------- ------- ------- Net Asset Value, End of Year ............... $ 4.48 $ 7.80 $ 7.60 $ 5.78 ======== ======= ======= ======= Total Return <F4> ........................... (22.39%) 16.24% 31.94% 18.88% Ratios/Supplemental Data Ratios to Average Net Assets: Operating and Management Expenses .......... 1.17% 0.81% 0.83% 0.85% Investment Income (Deficit) -- Net ......... 0.03% 0.04% 0.07% 0.49% Portfolio Turnover Rate<F3> ................. 80% 74% 83% 60% Net Assets, End of Year(thousands) ......... $442,020 $679,281 $722,546 $643,201 </TABLE> <F1> Calculation based on average shares outstanding. <F2> Prior to June 30, 1987, net commissions paid on new sales of shares under the Fund's Rule 12b-1 Distribution Plan had been treated for both financial statement and tax purposes as capital charges. On June 11, 1987, the Securities and Exchange Commission adopted a rule which required for financial statements for the periods ended on or after June 30, 1987, that net commissions paid under rule 12b-1 Distribution Plans be treated as operating expenses rather than capital charges. Accordingly, beginning with the year ended May 31, 1988, the Fund's financial statements reflect 12b-1 Distribution Plan expenses (i.e., shareholder service fees plus commissions paid net of deferred sales charges received by the Fund) as a component of the net investment income section of the financial highlights. <F3> Portfolio turnover rate for periods ended on or after May 31, 1986 includes certain U.S. Government obligations. <F4> Excluding applicable sales charges. <F5> Effective June 1, 1993, the Fund adopted Statement of Position 93-2: "Determination, Disclosure and Financial Statement Presentation of Income, Capital Gain and Return of Capital Distributions by Investment Companies." As a result, distribution amounts exceeding book basis net investment income (or tax basis net income on a temporary basis) are presented as "Distributions in excess of investment income -- net". Similarly, capital gain distributions in excess of book basis capital gains (or tax basis capital gains on a temporary basis) are presented as "Distributions in excess of realized capital gains." From January 31, 1990 until the date of adoption of the Statement of Position, distribution amounts exceeding book basis net investment income were charged to paid-in capital. 3

- -------------------------------------------------------------------------------- FUND DESCRIPTION - -------------------------------------------------------------------------------- The Fund is an open-end, diversified management investment company, commonly known as a mutual fund. The Fund was created under Pennsylvania law as a common law trust and has been offering its shares continuously since September 11, 1935. The Fund is one of twenty funds managed by Keystone Management, Inc. ("Keystone Management"), the Fund's investment manager, and is one of thirty-one funds managed or advised by Keystone Custodian Funds, Inc., ("Keystone"), the Fund's investment adviser. Keystone and Keystone Management are, from time to time, also collectively referred to as "Keystone." - -------------------------------------------------------------------------------- FUND OBJECTIVE AND POLICIES - -------------------------------------------------------------------------------- The Fund's investment objective is to provide shareholders with long-term growth of capital. It is the policy of the Fund to invest its assets, as fully as practicable, in common stocks, securities convertible into common stocks, securities having common stock characteristics (including rights and warrants), limited partnerships and master limited partnerships selected primarily for prospective capital growth. The class of securities from which these selections are made may be expected to experience wide fluctuations in price in both rising and declining markets. Investments in newer and smaller companies, particularly those believed to be in the earlier phases of growth, are favored. While income is not an objective, securities appearing to offer attractive possibilities for future growth of income may be included in the portfolio whenever it seems possible to do so without conflicting with the Fund's objective of capital growth. In addition to its other investment options, the Fund may invest up to 25% of its total assets in foreign securities. When market conditions warrant, the Fund may adopt a defensive position to preserve shareholders' capital by investing in money market instruments. Such instruments, which must mature within one year of their purchase, consist of United States ("U.S.") government securities; instruments, including certificates of deposit, demand and time deposits and bankers' acceptances, of banks that are members of the Federal Deposit Insurance Corporation and have assets of at least $1 billion, including U.S. branches of foreign banks and foreign branches of U.S. banks; prime commercial paper, including master demand notes; and repurchase agreements secured by U.S. government securities. The Fund intends to follow policies of the Securities and Exchange Commission as they are adopted from time to time with respect to illiquid securities, including, at this time, (1) treating as illiquid, securities which may not be sold or disposed of in the ordinary course of business within seven days at approximately the value at which the Fund has valued the investment on its books and (2) limiting its holdings of such securities to 15% of net assets. The Fund may write covered call options and purchase call options, including purchasing call options to close out existing positions, and may employ new investment techniques with respect to such options. The Fund currently does not intend to invest more than 5% of its assets in options transactions. The Fund may enter into reverse repurchase agreements and firm commitment agreements for securities and currencies. In addition, the Fund may enter into currency and other financial futures contracts and engage in related options transactions for hedging purposes and not for speculation and may employ new investment techniques with respect to such futures contracts and related options. The Fund may invest in restricted securities, including securities eligible for resale pursuant to Rule 144A under the Securities Act of 1933 (the "1933 Act"). Generally, Rule 144A establishes a safe harbor from the registration requirements of the 1933 Act for resales by large institutional investors of securities not publicly traded in the U.S. The Fund intends to purchase Rule 144A securities when such securities present an attractive investment opportunity and otherwise meet the Fund's selection criteria. The Board of Trustees has adopted guidelines and procedures pursuant to which Keystone 4

determines the liquidity of the Fund's Rule 144A securities. The Board monitors Keystone's implementation of such guidelines and procedures. At the present time, the Fund cannot accurately predict exactly how the market for Rule 144A securities will develop. A Rule 144A security that was readily marketable upon purchase may subsequently become illiquid. In such an event, the Board of Trustees will consider what action, if any, is appropriate. Investment in foreign securities, options securities, forward securities, structured securities and other complex securities (also known as "derivative instruments") transactions involves certain risks. For an explanation of these risks, see the "Additional Investment Information" section at the back of the prospectus and the statement of additional information. For further information generally about the types of investments and investment techniques available to the Fund and the risks associated, see "Additional Investment Information" and the statement of additional information. Of course, there can be no assurance that the Fund will achieve its investment objective since there is uncertainty in every investment. The investment objective of the Fund cannot be changed without a vote of the holders of a majority (as defined in the 1940 Act) of the Fund's outstanding shares. - -------------------------------------------------------------------------------- INVESTMENT RESTRICTIONS - -------------------------------------------------------------------------------- The Fund has adopted the fundamental restrictions described below, which may not be changed without the approval of a majority of the Fund's outstanding shares. These restrictions and certain other fundamental restrictions are more completely described in the statement of additional information. Generally, the Fund may not do the following: (1) invest more than 5% of its total assets, computed at market value at the time of purchase, in the securities of any one issuer (other than U.S. government securities) except that up to 25% of its total assets may be invested without regard to this limit; (2) borrow money, except that the Fund may borrow money from banks for temporary or emergency purposes in aggregate amounts up to 10% of the value of the Fund's net assets (computed at cost) or enter into reverse repurchase agreements provided that bank borrowings and reverse repurchase agreements, in aggregate, shall not exceed 10% of the value of the Fund's net assets; and (3) invest more than 25% of its total assets in securities of issuers in the same industry. In addition, the Fund may, notwithstanding any other investment policy or restriction, invest all of its assets in the securities of a single open-end management investment company with substantially the same fundamental investment objectives, policies and restrictions as the Fund. The Fund does not currently intend to implement this policy and would do so only if the Trustees were to determine such action to be in the best interest of the Fund and its shareholders. Furthermore, the Trustees will not authorize implementation of this policy so long as the Fund's shares are registered for sale in Japan and Japanese law prohibits such investment. In the event of such implementation, the Fund will comply with such requirements as to written notice to shareholders as are then in effect. - -------------------------------------------------------------------------------- PRICING SHARES - -------------------------------------------------------------------------------- The net asset value of a Fund share is computed each day on which the New York Stock Exchange (the "Exchange") is open as of the close of trading on the Exchange (currently 4:00 p.m. Eastern time for the purpose of pricing Fund shares) except on days when changes in the value of the Fund's securities do not affect the current net asset value of its shares. The Exchange currently is closed on weekends, New Year's Day, Presidents' Day, Good Friday, Memorial Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day. The net asset value per share is arrived at by determining the value of all of the Fund's assets, subtracting all liabilities and dividing the result by the number of shares outstanding. 5

The Fund values portfolio securities traded on an established exchange on the basis of the last sales price. Securities traded in the over-the-counter market, for which complete quotations are available, are valued at the mean of the bid and the asked prices. The Fund values the money market instruments it purchases as follows: short-term money market instruments purchased with maturities of sixty days or less are valued at amortized cost (original purchase cost as adjusted for amortization of premium or accretion of discount), which, when combined with accrued interest, approximates market; money market instruments maturing in more than sixty days for which market quotations are readily available are valued at current market value; and money market instruments maturing in more than sixty days when purchased that are held on the sixtieth day prior to maturity are valued at amortized cost (market value on the sixtieth day adjusted for amortization of premium or accretion of discount), which, when combined with accrued interest, approximates market, in any case reflecting fair value as determined by the Fund's Board of Trustees. All other investments are valued at market value or, where market quotations are not readily available, at fair value as determined in good faith by the Fund's Board of Trustees. See "Valuation of Securities" in the Fund's statement of additional information. - -------------------------------------------------------------------------------- DIVIDENDS AND TAXES - -------------------------------------------------------------------------------- The Fund has qualified and intends to qualify in the future as a regulated investment company under the Internal Revenue Code. The Fund qualifies if, among other things, it distributes to its shareholders at least 90% of its net investment income for its fiscal year. The Fund also intends to make timely distributions, if necessary, sufficient in amount to avoid the nondeductible 4% excise tax imposed on a regulated investment company when it fails to distribute, with respect to each calendar year, at least 98% of its ordinary income for such calendar year and 98% of its net capital gains for the one-year period ending on October 31 of such calendar year. Any such distributions would be (1) declared on or before December 31 to shareholders of record in December, (2) paid by the following January 31, and (3) includable in the taxable income of shareholders for the year in which such distributions were declared. If the Fund qualifies and if it distributes all of its net investment income and net capital gains, if any, to shareholders, it will be relieved of any federal income tax liability. The Fund distributes its net income to its shareholders and net capital gains at least annually. Commissions paid by the Fund on new sales of shares under the Fund's Distribution Plan (see "Distribution Plan") and deferred sales charge receipts are treated as capital charges and capital credits, respectively, in determining net investment income for tax purposes. For financial statement purposes, however, these commissions and receipts are treated as operating expenses and expense offsets. As a result, the amount of dividend distributions required to satisfy the requirements of the Internal Revenue Code might exceed net investment income for financial statement purposes, resulting in a portion of such dividends being a distribution in excess of net investment income for financial statement purposes. Total investment return is equally affected by both treatments. The Fund makes distributions in additional shares of the Fund or at the shareholder's election (which must be made before the record date for the distribution) in cash. Income dividends and net short-term gains distributions are taxable as ordinary income and net long-term gains are taxable as capital gains regardless of how long the shareholder has held the Fund's shares. If Fund shares held for less than six months are sold at a loss, however, such loss will be treated for tax purposes as a long-term capital loss to the extent of any long-term capital gains dividends received. Dividends and distributions may also be subject to state and local taxes. The Fund advises its shareholders annually as to the federal tax status of all distributions made during the year. 6

- -------------------------------------------------------------------------------- FUND MANAGEMENT AND EXPENSES - -------------------------------------------------------------------------------- FUND MANAGEMENT Subject to the general supervision of the Fund's Board of Trustees, Keystone Management located at 200 Berkeley Street, Boston, Massachusetts 02116-5034, serves as investment manager to the Fund and is responsible for the overall management of the Fund's business and affairs. Keystone Management, organized in 1989, is a wholly-owned subsidiary of Keystone. Its directors and principal executive officers have been affiliated with Keystone, a seasoned investment adviser, for a number of years. Keystone Management also serves as investment manager to each of the other Keystone Custodian Funds and to certain other funds in the Keystone Group of Mutual Funds. The Fund pays Keystone Management a fee for its services at the annual rate of: Annual Aggregate Net Asset Value Management of the Shares Fee of the Fund - -------------------------------------------------------------------------------- 0.70% of the first $ 100,000,000, plus 0.65% of the next $ 100,000,000, plus 0.60% of the next $ 100,000,000, plus 0.55% of the next $ 100,000,000, plus 0.50% of the next $ 100,000,000, plus 0.45% of the next $ 500,000,000, plus 0.40% of the next $ 500,000,000, plus 0.35% of amounts over $1,500,000,000; computed as of the close of business each business day and paid daily. Pursuant to its Investment Management Agreement with the Fund, Keystone Management has delegated its investment management functions, except for certain administrative and management services to Keystone and has entered into an Investment Advisory Agreement with Keystone under which Keystone provides investment advisory and management services to the Fund. Services performed by Keystone Management include (1) performing research and planning with respect to (a) the Fund's qualification as a regulated investment company under Subchapter M of the Internal Revenue Code, (b) tax treatment of the Fund's portfolio investments, (c) tax treatment of special corporate actions (such as reorganizations), (d) state tax matters affecting the Fund, and (e) the Fund's distributions of income and capital gains; (2) preparing the Fund's federal and state tax returns; (3) providing services to the Fund's shareholders in connection with federal and state taxation and distributions of income and capital gains; and (4) storing documents relating to the Fund's activities. Keystone, located at 200 Berkeley Street, Boston, Massachusetts 02116-5034, has provided investment advisory and management services to investment companies and private accounts since it was organized in 1932. Keystone is a wholly-owned subsidiary of Keystone Group, Inc. ("Keystone Group"), 200 Berkeley Street, Boston, Massachusetts 02116-5034. Keystone Group is a corporation privately owned by current and former members of management of Keystone and its affiliates. The shares of Keystone Group common stock beneficially owned by management are held in a number of voting trusts, the trustees of which are George S. Bissell, Albert H. Elfner, III, Roger T. Wickers, Edward F. Godfrey and Ralph J. Spuehler, Jr. Keystone Group provides accounting, bookkeeping, legal, personnel and general corporate services to Keystone Management, Keystone, their affiliates and the Keystone Group of Mutual Funds. Pursuant to the Investment Advisory Agreement, Keystone receives for its services an annual fee representing 85% of the management fee received by Keystone Management under its Investment Management Agreement with the Fund. During the year ended May 31, 1994, the Fund paid or accrued to Keystone Management investment management and administrative services fees of $5,433,201, which represented 0.52% of the Fund's average net assets. Of such amount paid to Keystone Management, $4,618,221 was paid to Keystone for its services to the Fund. FUND EXPENSES In addition to the investment advisory and management fees discussed above, the principal expenses the Fund is expected to pay include, but are not limited 7

to, expenses of its transfer agent, its custodian and its independent auditors; expenses under its Distribution Plan; fees of its Independent Trustees ("Independent Trustees"); expenses of shareholders' and Trustees' meetings; fees payable to government agencies, including registration and qualification fees of the Fund and its shares under federal and state securities laws; expenses of preparing, printing and mailing Fund prospectuses, notices, reports and proxy material; and certain extraordinary expenses. In addition to such expenses, the Fund pays its brokerage commissions, interest charges and taxes. For the fiscal year ended May 31, 1994, the Fund paid 1.73% of its average net assets in expenses. During the fiscal year ended May 31, 1994, the Fund paid or accrued to Keystone Investor Resource Center, Inc. ("KIRC"), the Fund's transfer and dividend disbursing agent, $24,577 for certain accounting and printing services and $2,387,258 for transfer agent services. KIRC is a wholly-owned subsidiary of Keystone. PORTFOLIO MANAGER Roland Gillis has been the Fund's Portfolio Manager since 1986. He is a Keystone Vice President and Senior Portfolio Manager and has more than 19 years' experience in equity investing. SECURITIES TRANSACTIONS Keystone selects broker-dealers to execute transactions subject to the receipt of best execution. When selecting broker-dealers to execute portfolio transactions for the Fund, Keystone may follow a policy of considering as a factor the number of shares of the Fund sold by such broker-dealers. In addition, broker-dealers may, from time to time, be affiliated with the Fund, Keystone Management, Keystone, the Fund's principal underwriter or their affiliates. PORTFOLIO TURNOVER The Fund's portfolio turnover rates for the fiscal years ended May 31, 1993 and 1994 were 78% and 60%, respectively. - -------------------------------------------------------------------------------- HOW TO BUY SHARES - -------------------------------------------------------------------------------- Shares of the Fund may be purchased from any broker-dealer that has a selling agreement with Keystone Distributors, Inc. ("KDI"), the Fund's principal underwriter ("Principal Underwriter"). KDI, a wholly-owned subsidiary of Keystone, is located at 200 Berkeley Street, Boston, Massachusetts 02116-5034. In addition, you may open an account for the purchase of shares of a Fund by mailing to the Fund, c/o KIRC, P.O. Box 2121, Boston, Massachusetts 02106-2121, a completed account application and a check payable to the Fund. Or you may telephone 1-800-343-2898 to obtain the number of an account to which you can wire or electronically transfer funds and then send in a completed account application. Subsequent investments in a Fund's shares in any amount may be made by check, by wiring federal funds or by an electronic funds transfer ("EFT"). The Fund's shares are sold at the net asset value per share next computed after it receives the purchase order. The initial purchase must be at least $1,000 except for purchases by participants in certain retirement plans for which the minimum is waived. There is no minimum for subsequent purchases. Purchase payments are fully invested at net asset value. The Fund does not impose a sales charge on purchases of Fund shares at the time of purchase. CONTINGENT DEFERRED SALES CHARGE With certain exceptions, when shares are redeemed within four calendar years after their purchase, a contingent deferred sales charge may be imposed at rates ranging from a maximum of 4% of amounts redeemed during the same calendar year of purchase to 1% of amounts redeemed during the third calendar year after the year of purchase. No contingent deferred sales charge is imposed on amounts redeemed thereafter or on shares purchased through reinvestment of dividends. If imposed, the contingent deferred sales charge is deducted from the redemption 8

proceeds otherwise payable to the shareholder. Prior to July 8, 1992, the Fund retained the contingent deferred sales charge. Since July 8, 1992, the contingent deferred sales charge attributable to shares purchased prior to January 1, 1992 has been retained by the Fund, and the contingent deferred sales charge attributable to shares purchased after January 1, 1992 is, to the extent permitted by the NASD, paid to KDI. For the fiscal year ended May 31, 1994, the Fund recovered $128,350 in deferred sales charges. The contingent deferred sales charge is a declining percentage of the lesser of (1) the net asset value of the shares redeemed or (2) the total cost of such shares. No deferred sales charge is imposed when a shareholder redeems amounts derived from (1) increases in the value of his account above the total cost of such shares due to increases in the net asset value per share of the Fund; (2) certain shares with respect to which the Fund did not pay a commission on issuance, including shares acquired through reinvestment of dividend income and capital gains distributions; or (3) shares held in all or part of four consecutive calendar years. In determining whether a contingent deferred sales charge is payable and, if so, the percentage charge applicable, it is assumed that shares held the longest are the first to be redeemed. No deferred sales charge is payable on permitted exchanges of shares between Keystone funds that have adopted Distribution Plans pursuant to Rule 12b-1 under the 1940 Act. Moreover, when shares of one such fund have been exchanged for shares of another such fund, for purposes of any future contingent deferred sales charge, the calendar year of the purchase of the shares of the fund exchanged into is assumed to be the year shares tendered for exchange were originally purchased. In addition, no contingent deferred sales charge is imposed on a redemption of shares of the Fund in the event of (1) death or disability of the shareholder; (2) a lump-sum distribution from a 401(k) plan or other benefit plan qualified under the Employee Retirement Income Security Act of 1974 ("ERISA"); (3) automatic withdrawals from ERISA plans if the shareholder is at least 59 1/2 years old; (4) involuntary redemptions of accounts having an aggregate net asset value of less than $1,000; or (5) automatic withdrawals under an automatic withdrawal plan of up to 1-1/2% per month of the shareholder's initial account balance. WAIVER OF DEFERRED SALES CHARGES Shares also may be sold, to the extent permitted by applicable law, at net asset value without the payment of commissions or the imposition of an initial sales charge or a deferred sales charge to (1) certain officers, Directors, Trustees and employees of the Fund, Keystone Management, Keystone and certain of their affiliates; (2) registered representatives of firms with dealer agreements with KDI; and (3) a bank or trust company acting as trustee for a single account. - -------------------------------------------------------------------------------- DISTRIBUTION PLAN - -------------------------------------------------------------------------------- The Fund bears some of the costs of selling its shares under its Distribution Plan adopted on June 1, 1983 pursuant to Rule 12b-1 under the 1940 Act. The Fund's Distribution Plan provides that the Fund may expend up to 0.3125% quarterly (approximately 1.25% annually) of the average daily net asset value of its shares to pay distribution costs for sales of its shares and to pay shareholder service fees. The NASD currently limits such annual expenditures to 1%, of which 0.75% may be used to pay such distribution costs and 0.25% may be used to pay shareholder service fees. The aggregate amount that the Fund may pay for such distribution costs is limited to 6.25% of gross share sales since the inception of the Fund's Distribution Plan plus interest at the prime rate plus 1% on unpaid amounts thereof (less any contingent deferred sales charges paid by shareholders to KDI). Amounts paid under the Distribution Plan are paid to the Fund's Principal Underwriter, currently KDI, (1) as commissions for Fund shares sold under the Distribution Plan, all or any part of which commissions may be reallowed by KDI to others for selling the Fund's shares, and (2) to enable KDI to pay such others shareholder service fees in respect of shares sold by them after the 9

inception of the Distribution Plan and remaining outstanding on the Fund's books for specified periods. Amounts paid or accrued to KDI under (1) and (2) in the aggregate may not exceed the limitation referred to above. From the amounts received by KDI in connection with the Distribution Plan, and subject to the limitations discussed above, KDI generally pays brokers or others a commission equal to 4% of the price paid to the Fund for each sale of Fund shares as well as a shareholder service fee at a rate of 0.25% per annum of the net asset value of shares sold by such brokers or others and remaining outstanding on the books of the Fund for specified periods. If the Fund is unable to pay KDI a commission on a new sale because the annual maximum (0.75% of average daily net assets) has been reached, KDI intends, but is not obligated, to continue to accept new orders for the purchase of Fund shares and to pay or accrue commissions and service fees to dealers in excess of the amount it currently receives from the Fund. While the Fund is under no contractual obligation to pay KDI such amounts that exceed the Distribution Plan limitation, KDI intends to seek full payment of such charges from the Fund (together with interest at the rate of prime plus one percent) at such time in the future as, and to the extent that, payment thereof by the Fund would be within permitted limits. KDI currently intends to seek payment of interest only on such charges paid or accrued by KDI subsequent to January 1, 1992. If the Fund's Independent Trustees authorize such payments, the effect will be to extend the period of time during which the Fund incurs the maximum amount of costs allowed by the Distribution Plan. If the Distribution Plan is terminated, KDI will ask the Independent Trustees to take whatever action they deem appropriate under the circumstances with respect to payment of such amounts. During the fiscal year ended May 31, 1994, the Fund paid KDI $9,900,583 under the Distribution Plan. The amount paid by the Fund under its Distribution Plan, net of deferred sales charges, was $9,772,233 (0.93% of the Fund's average daily net asset value during the year). During the year, KDI retained $3,999,703 and paid commissions on new sales and service fees to others of $7,941,992, of which $2,041,112 was an advance. During the same year, KDI received $879,228 in deferred sales charges. Total advances outstanding as of May 31, 1994 were $2,344,026 (0.23% of the Fund's net asset value as of such year-end). The amounts and purposes of expenditures under the Distribution Plan must be reported to the Independent Trustees quarterly. The Independent Trustees may require or approve changes in the operation of the Distribution Plan and may require that total expenditures by the Fund under the Distribution Plan be kept within limits lower than the maximum amount permitted by the Distribution Plan, as stated above. If such costs are not limited by the Independent Trustees, such costs could, for some period of time, be higher than such costs permitted by most other plans presently adopted by other investment companies. The Distribution Plan may be terminated at any time by vote of the Independent Trustees or by vote of a majority of the outstanding voting shares of the Fund. Any change in the Distribution Plan that would materially increase the distribution expenses of the Fund provided for in the Distribution Plan requires shareholder approval. Otherwise, the Distribution Plan may be amended by votes of the majority of both (1) the Fund's Trustees and (2) the Independent Trustees, cast in person at a meeting called for the purpose of voting on such amendment. While the Distribution Plan is in effect, the Fund is required to commit the selection and nomination of candidates for Independent Trustees to the discretion of the Independent Trustees. Whether any expenditure under the Distribution Plan is subject to a state expense limit depends upon the nature of the expenditure and the terms of the state law, regulation or order imposing the limit. A portion of the Fund's Distribution Plan expenses may be includable in the Fund's total operating expenses for purposes of determining compliance with state expense limits. 10

Upon written notice to dealers, KDI, at its own expense may periodically sponsor programs that offer additional compensation in connection with sales of Fund shares. Participation in such programs may be available to all dealers or to selected dealers who have sold or are expected to sell significant amounts of shares. Additional compensation may also include financial assistance to dealers in connection with preapproved seminars, conferences and advertising. No such programs or additional compensation will be offered to the extent they are prohibited by the laws of any state or any self-regulatory agency, such as the NASD. The Glass-Steagall Act currently limits the ability of a depository institution (such as a commercial bank or a savings and loan association) to become an underwriter or distributor of securities. In the event the Glass-Steagall Act is deemed to prohibit depository institutions from accepting payments under the arrangement described above, or should Congress relax current restrictions on depository institutions, the Board of Trustees will consider what action, if any, is appropriate. In addition, state securities laws on this issue may differ from the interpretations of federal law expressed herein, and banks and financial institutions may be required to register as dealers pursuant to state law. - -------------------------------------------------------------------------------- HOW TO REDEEM SHARES - -------------------------------------------------------------------------------- Fund shares may be redeemed for cash at the redemption value upon written order by the shareholder(s) to the Fund c/o Keystone Investor Resource Center, Inc., Box 2121, Boston, Massachusetts 02106-2121, and presentation to the Fund of a properly endorsed share certificate if certificates have been issued. The signature(s) of the shareholder(s) on the written order and certificates must be guaranteed. The redemption value is the net asset value adjusted for fractions of a cent and may be more or less than the shareholder's cost depending upon changes in the value of the Fund's portfolio securities between purchase and redemption. The Fund may impose a deferred sales charge at the time of redemption of certain shares as explained in "How to Buy Shares." If imposed, the Fund deducts the deferred sales charge from the redemption proceeds otherwise payable to the shareholder. At various times, the Fund may be requested to redeem shares for which it has not yet received good payment. In such a case, the Fund will mail the redemption proceeds upon clearance of the purchase check, which may take up to 15 days or more. Any delay may be avoided by purchasing shares either with a certified check or by bank wire of funds. Although the mailing of a redemption check may be delayed, the redemption value will be determined and the redemption processed in the ordinary course of business upon receipt of proper documentation. In such a case, after redemption and prior to the release of the proceeds, no appreciation or depreciation will occur in the value of the redeemed shares, and no interest will be paid on the redemption proceeds. If the mailing of a redemption check has been delayed, the check will be mailed promptly after good payment has been collected. The Fund computes the redemption value at the close of the Exchange at the end of the day on which it has received all proper documentation from the shareholder. Payment of the amount due on redemption, less any applicable deferred sales charge, will be made within seven days thereafter. Shareholders may also redeem their shares through their broker-dealers. KDI, acting as agent for the Fund, stands ready to repurchase Fund shares upon orders from dealers as follows: redemption requests received by broker-dealers prior to that day's close of trading on the Exchange and transmitted to the Fund prior to its close of business that day will receive the net asset value price computed at the close of trading on the Exchange on the same day. Redemption requests received by broker-dealers after that day's close of trading on the Exchange and transmitted to the Fund prior to the close of business on the next business day will receive the next business day's net asset value price. If KDI has received proper documentation, it will pay the redemption proceeds, less any applicable deferred sales charge, to the dealer placing the order within seven days 11

thereafter. KDI charges no fees for this service. Your broker-dealer, however, may do so. For the protection of shareholders, SIGNATURES ON CERTIFICATES, STOCK POWERS AND ALL WRITTEN ORDERS OR AUTHORIZATIONS MUST BE GUARANTEED BY A U.S. STOCK EXCHANGE MEMBER, A U.S. COMMERCIAL BANK OR TRUST COMPANY OR OTHER PERSONS ELIGIBLE TO GUARANTEE SIGNATURES UNDER THE SECURITIES EXCHANGE ACT OF 1934 AND KIRC'S POLICIES. The Fund and KIRC may waive this requirement, but may also require additional documents in certain cases. Currently, the requirement for a signature guarantee has been waived on redemptions of $50,000 or less where the account address of record has been the same for a minimum period of 30 days. The Fund and KIRC reserve the right to withdraw this waiver at any time. If the Fund receives a redemption or repurchase order, but the shareholder has not clearly indicated the amount of money or number of shares involved, the Fund cannot execute the order. In such cases, the Fund will request the missing information from the shareholder and process the order the day it receives such information. TELEPHONE Under ordinary circumstances, you may redeem up to $50,000 from your account by telephone by calling toll free 1-800-343-2898. In order to insure that instructions received by KIRC are genuine, when you initiate a telephone transaction, you will be asked to verify certain criteria specific to your account. At the conclusion of the transaction, you will be given a transaction number confirming your request, and written confirmation of your transaction will be mailed the next business day. Your telephone instructions will be recorded. Redemptions by telephone are allowed only if the address and bank account of record have been the same for a minimum period of 30 days. If the redemption proceeds are less than $2,500, they will be mailed by check. If they are $2,500 or more, they will be mailed, wired or sent by EFT to your previously designated bank account as you direct. If you do not specify how you wish your redemption proceeds to be sent, they will be mailed by check. If you cannot reach the Fund by telephone, you should follow the procedures for redeeming by mail or through a broker as set forth herein. SMALL ACCOUNTS Because of the high cost of maintaining small accounts, the Fund reserves the right to redeem your account if its value falls below $1,000, the current minimum investment level, as a result of your redemptions (but not as a result of market action). You will be notified in writing and allowed 60 days to increase the value of your account to the minimum investment level. No contingent deferred sales charges are applied to such redemptions. GENERAL The Fund reserves the right at any time to terminate, suspend or change the terms of any redemption method described in this prospectus, except redemption by mail, and to impose fees. Except as otherwise noted, neither the Fund, KIRC nor KDI assumes responsibility for the authenticity of any instructions received by any of them from a shareholder in writing, over the Keystone Automated Response Line ("KARL") or by telephone. KIRC will employ reasonable procedures to confirm that instructions received over KARL or by telephone are genuine. Neither the Fund, KIRC nor KDI will be liable when following instructions received over KARL or by telephone that KIRC reasonably believes to be genuine. The Fund may temporarily suspend the right to redeem its shares when (1) the Exchange is closed, other than customary weekend and holiday closings; (2) trading on the Exchange is restricted; (3) the Fund cannot dispose of its investments or fairly determine their value; or (4) the Securities and Exchange Commission, for the protection of shareholders, so orders. 12

- -------------------------------------------------------------------------------- SHAREHOLDER SERVICES - -------------------------------------------------------------------------------- Details on all shareholder services may be obtained from KIRC by writing or by calling toll free 1-800-343-2898. KEYSTONE AUTOMATED RESPONSE LINE The Keystone Automated Response Line offers shareholders specific fund account information and price and yield quotations as well as the ability to effect account transactions, including investments, exchanges and redemptions. Shareholders may access KARL by dialing toll free 1-800-346-3858 on any touch-tone telephone, 24 hours a day, seven days a week. EXCHANGES A shareholder who has obtained the appropriate prospectus may exchange shares of the Fund for shares of any of the other seven Keystone Custodian Funds, Keystone Precious Metals Holdings, Inc. ("KPMH"), Keystone International Fund Inc. ("KIF"), Keystone Tax Exempt Trust ("KTET"), Keystone Liquid Trust ("KLT") or Keystone Tax Free Fund ("KTFF") on the basis of their respective net asset values by calling toll free 1-800-343-2898 or by writing KIRC at Box 2121, Boston, Massachusetts 02106-2121. Fund shares purchased by check may be exchanged for shares of the named funds, other than KPMH, KTET or KTFF, after 15 days provided good payment for the purchase of Fund shares has been collected. In order to exchange Fund shares for shares of KPMH, KTET or KTFF, a shareholder must have held Fund shares for a period of at least six months. There is no exchange fee for exchanges initiated by an individual investor through KARL; other exchanges made by phone are subject to a $10 exchange fee. If the shares being tendered for exchange have been held for less than four years and are still subject to a contingent deferred sales charge, such charge will carry over to the shares being acquired in the exchange transaction. The Fund reserves the right, after providing shareholders with any required notice, to terminate this exchange offer or to change its terms, including the right to change the service charge for any exchange. Orders to exchange shares of the Fund for shares of KLT will be executed by redeeming the shares of the Fund and purchasing shares of KLT at the net asset value of KLT shares determined after the proceeds from such redemption become available, which may be up to seven days after such redemption. In all other cases, orders for exchanges received by the Fund prior to 4:00 p.m. on any day the funds are open for business will be executed at the respective net asset values determined as of the close of business that day. Orders for exchanges received after 4:00 p.m. on any business day will be executed at the respective net asset values determined at the close of the next business day. An excessive number of exchanges may be disadvantageous to the Fund. Therefore, the Fund, in addition to its right to reject any exchange, reserves the right to terminate the exchange privilege of any shareholder who makes more than five exchanges of shares of the funds in a year or three in a calendar quarter. An exchange order must comply with the requirements for a redemption or repurchase order and must specify the dollar value or number of shares to be exchanged. Exchanges are subject to the minimum initial purchase requirements of the fund being acquired. An exchange constitutes a sale for federal income tax purposes. The exchange privilege is available only in states where shares of the fund being acquired may legally be sold. RETIREMENT PLANS The Fund has various pension and profit-sharing plans available to investors, including Individual Retirement Accounts ("IRAs"); Rollover IRAs; Simplified Employee Pension Plans ("SEPs"); Tax Sheltered Annuity Plans ("TSAs"); 401(k) Plans; Keogh Plans; Corporate Profit-Sharing Plans; Pension and Target Benefit Plans; Money Purchase Pension Plans; and Salary-Reduction Plans. For details, including fees and application forms, call KIRC toll free at 1-800-247-4075 or write to KIRC at P.O. Box 2121, Boston, Massachusetts 02106-2121. 13

AUTOMATIC INVESTMENT PLAN Shareholders may take advantage of investing on an automatic basis by establishing an automatic investment plan. Checks are drawn on a shareholder's checking account monthly and used to purchase Fund shares. AUTOMATIC WITHDRAWAL PLAN Under an Automatic Withdrawal Plan, shareholders may arrange for regular monthly or quarterly fixed withdrawal payments. Each payment must be at least $100 and may be as much as 1% per month or 3% per quarter of the total net asset value of the Fund shares in the shareholder's account when the Automatic Withdrawal Plan is opened. Fixed withdrawal payments are not subject to a deferred sales charge. Excessive withdrawals may decrease or deplete the value of a shareholder's account. OTHER SERVICES Under certain circumstances, shareholders may, within 30 days after a redemption, reinstate their accounts at current net asset value. Further details may be obtained from KIRC by calling toll free 1-800-343-2898 or by writing KIRC at P.O. Box 2121, Boston, Massachusetts 02106-2121. - -------------------------------------------------------------------------------- PERFORMANCE DATA - -------------------------------------------------------------------------------- From time to time, the Fund may advertise "total return" and "current yield." BOTH FIGURES ARE BASED ON HISTORICAL EARNINGS AND ARE NOT INTENDED TO INDICATE FUTURE PERFORMANCE. Total return refers to the Fund's average annual compounded rates of return over specified periods determined by comparing the initial amount invested to the ending redeemable value of that amount. The resulting equation assumes reinvestment of all dividends and distributions and deduction of all recurring charges applicable to all shareholder accounts. The deduction of the contingent deferred sales charge is reflected in the applicable years. The exchange fee is not included in the calculation. Current yield quotations represent the yield on an investment for a stated 30-day period computed by dividing net investment income earned per share during the base period by the maximum offering price per share on the last day of the base period. The Fund presently does not intend to advertise current yield. The Fund may include comparative performance information in advertising or marketing the Fund's shares, such as data from Lipper Analytical Services, Inc. or other industry publications. - -------------------------------------------------------------------------------- FUND SHARES - -------------------------------------------------------------------------------- The Fund currently issues one class of shares, which participate equally in dividends and distributions and have equal voting, liquidation and other rights. When issued and paid for, the shares will be fully paid and nonassessable by the Fund. Shares may be exchanged as explained under "Shareholder Services," but will have no other preference, conversion, exchange or preemptive rights. Shareholders are entitled to one vote for each full share owned and fractional votes for fractional shares. Shares are redeemable, transferable and freely assignable as collateral. There are no sinking fund provisions. The Fund may establish additional classes or series of shares. The Fund does not have annual meetings. The Fund will have special meetings from time to time as required under its Declaration of Trust and under the 1940 Act. As provided in the Fund's Declaration of Trust, shareholders have the right to remove Trustees by an affirmative vote of two-thirds of the outstanding shares. A special meeting of the shareholders will be held when 10% of the outstanding shares request a meeting for the purpose of removing a Trustee. The Fund is prepared to assist shareholders in communications with one another for the purpose of convening such a meeting as prescribed by Section 16(c) of the 1940 Act. - -------------------------------------------------------------------------------- ADDITIONAL INFORMATION - -------------------------------------------------------------------------------- KIRC, located at 101 Main Street, Cambridge, Massachusetts 02142-1519, is a wholly-owned subsidiary of Keystone and serves as the Fund's transfer agent and 14

dividend disbursing agent. When the Fund determines from its records that more than one account in the Fund is registered in the name of a shareholder or shareholders having the same address, upon written notice to those shareholders, the Fund intends, when an annual report or semi-annual report of the Fund is required to be furnished, to mail one copy of such report to that address. Except as otherwise stated in this prospectus or required by law, the Fund reserves the right to change the terms of the offer stated in this prospectus without shareholder approval, including the right to impose or change fees for services provided. 15

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- -------------------------------------------------------------------------------- ADDITIONAL INVESTMENT INFORMATION - -------------------------------------------------------------------------------- DESCRIPTIONS OF CERTAIN TYPES OF INVESTMENTS AND INVESTMENT TECHNIQUES AVAILABLE TO THE FUND OBLIGATIONS OF FOREIGN BRANCHES OF UNITED STATES BANKS The obligations of foreign branches of U.S. banks may be general obligations of the parent bank in addition to the issuing branch or may be limited by the terms of a specific obligation and by government regulation. Payment of interest and principal upon these obligations may also be affected by governmental action in the country of domicile of the branch (generally referred to as sovereign risk). In addition, evidences of ownership of such securities may be held outside the U.S., and the Fund may be subject to the risks associated with the holding of such property overseas. Various provisions of federal law governing domestic branches do not apply to foreign branches of domestic banks. OBLIGATIONS OF UNITED STATES BRANCHES OF FOREIGN BANKS Obligations of U.S. branches of foreign banks may be general obligations of the parent bank in addition to the issuing branch or may be limited by the terms of a specific obligation and by federal and state regulation as well as by governmental action in the country in which the foreign bank has its head office. In addition, there may be less publicly available information about a U.S. branch of a foreign bank than about a domestic bank. MASTER DEMAND NOTES Master demand notes are unsecured obligations that permit the investment of fluctuating amounts by the Fund at varying rates of interest pursuant to direct arrangements between the Fund, as lender, and the issuer, as borrower. The Fund has the right to increase the amount at any time up to the full amount provided by the note agreement or to decrease the amount. The borrower may repay up to the full amount of the note without penalty. Notes purchased by the Fund permit the Fund to demand payment of principal and accrued interest at any time (on not more than seven days' notice). Notes acquired by the Fund may have maturities of more than one year, provided that (1) the Fund is entitled to payment of principal and accrued interest upon not more than seven days notice, and (2) the rate of interest on such notes is adjusted automatically at periodic intervals, which normally will not exceed 31 days, but may extend up to one year. The notes are deemed to have a maturity equal to the longer of the period remaining to the next interest rate adjustment or the demand notice period. Because these types of notes are direct lending arrangements between the lender and the borrower, such instruments are not normally traded and there is no secondary market for these notes, although they are redeemable and thus repayable by the borrower at face value plus accrued interest at any time. Accordingly, the Fund's right to redeem is dependent on the ability of the borrower to pay principal and interest on demand. In connection with master demand note arrangements, Keystone considers, under standards established by the Board of Trustees, earning power, cash flow and other liquidity ratios of the borrower and will monitor the ability of the borrower to pay principal and interest on demand. These notes are not typically rated by credit rating agencies. Unless rated, the Fund will invest in them only if the issuer meets the criteria established for commercial paper. REPURCHASE AGREEMENTS The Fund may enter into repurchase agreements with member banks of the Federal Reserve System having at least $1 billion in assets, primary dealers in U.S. government securities or other financial institutions believed by Keystone to be creditworthy. Such persons must be registered as U.S. government securities dealers with appropriate regulatory organizations. Under such agreements, the bank, primary dealer or other financial institution agrees to repurchase the (i)

security at a mutually agreed upon date and price, thereby determining the yield during the term of the agreement. This results in a fixed rate of return insulated from market fluctuations during such period. Under a repurchase agreement, the seller must maintain the value of the securities subject to the agreement at not less than the repurchase price, such value being determined on a daily basis by marking the underlying securities to their market value. Although the securities subject to the repurchase agreement might bear maturities exceeding a year, the Fund only intends to enter into repurchase agreements that provide for settlement within a year and usually within seven days. Securities subject to repurchase agreements will be held by the Fund's custodian or in the Federal Reserve book entry system. The Fund does not bear the risk of a decline in the value of the underlying security unless the seller defaults under its repurchase obligation. In the event of a bankruptcy or other default of a seller of a repurchase agreement, the Fund could experience both delays in liquidating the underlying securities and losses, including (1) possible declines in the value of the underlying securities during the period while the Fund seeks to enforce its rights thereto; (2) possible subnormal levels of income and lack of access to income during this period; and (3) expenses of enforcing its rights. The Board of Trustees has established procedures to evaluate the creditworthiness of each party with whom the Fund enters into repurchase agreements by setting guidelines and standards of review for Keystone and monitoring Keystone's actions with regard to repurchase agreements. REVERSE REPURCHASE AGREEMENTS Under a reverse repurchase agreement, the Fund would sell securities and agree to repurchase them at a mutually agreed upon date and price. The Fund intends to enter into reverse repurchase agreements to avoid otherwise having to sell securities during unfavorable market conditions in order to meet redemptions. At the time the Fund enters into a reverse repurchase agreement, it will establish a segregated account with the Fund's custodian containing liquid assets having a value not less than the repurchase price (including accrued interest) and will subsequently monitor the account to ensure such value is maintained. Reverse repurchase agreements involve the risk that the market value of the securities the Fund is obligated to repurchase may decline below the repurchase price. Borrowing and reverse repurchase agreements magnify the potential for gain or loss on the portfolio securities of the Fund and, therefore, increase the possibility of fluctuation in the Fund's net asset value. Such practices may constitute leveraging. In the event the buyer of securities under a reverse repurchase agreement files for bankruptcy or becomes insolvent, such buyer or its trustee or receiver may receive an extension of time to determine whether to enforce the Fund's obligation to repurchase the securities, and the Fund's use of the proceeds of the reverse repurchase agreement may effectively be restricted pending such determination. The staff of the Securities and Exchange Commission has taken the position that the 1940 Act treats reverse repurchase agreements as being included in the percentage limit on borrowings imposed on a Fund. "WHEN ISSUED" SECURITIES The Fund may also purchase and sell securities and currencies on a when issued and delayed delivery basis. When issued or delayed delivery transactions arise when securities or currencies are purchased or sold by the Fund with payment and delivery taking place in the future in order to secure what is considered to be an advantageous price and yield to the Fund at the time of entering into the transaction. When the Fund engages in when issued and delayed delivery transactions, the Fund relies on the buyer or seller, as the case may be, to consummate the sale. Failure to do so may result in the Fund missing the opportunity to obtain a price or yield considered to be advantageous. When issued and delayed delivery transactions may be expected to occur a month or more before delivery is due. No payment or delivery is made by the Fund, however, until it receives payment or delivery from the other party to the transaction. The Fund will maintain a separate account of liquid assets equal to the value of such purchase commitments until payment is made. When issued and delayed delivery agreements are subject to risks from changes in value based (ii)

upon changes in the level of interest rates, currency rates and other market factors, both before and after delivery. The Fund does not accrue any income on such securities or currencies prior to their delivery. To the extent the Fund engages in when issued and delayed delivery transactions, it will do so for the purpose of acquiring portfolio securities consistent with its investment objective and policies and not for the purpose of investment leverage. FOREIGN SECURITIES The Fund may invest up to 25% of its assets in securities principally traded in securities markets outside the U.S. While investment in foreign securities is intended to reduce risk by providing further diversification, such investments involve sovereign risk in addition to the credit and market risks normally associated with domestic securities. Foreign investments may be affected favorably or unfavorably by changes in currency rates and exchange control regulations. There may be less publicly available information about a foreign company than about a U.S. company, and foreign companies may not be subject to accounting, auditing and financial reporting standards and requirements comparable to those applicable to U.S. companies. Securities of some foreign companies are less liquid or more volatile than securities of U.S. companies, and foreign brokerage commissions and custodian fees are generally higher than in the United States. Investments in foreign securities may also be subject to other risks different from those affecting U.S. investments, including local political or economic developments, expropriation or nationalization of assets, imposition of withholding taxes on dividend or interest payments and currency blockage (which would prevent cash from being brought back to the U.S.). These risks are carefully considered by Keystone prior to the purchase of these securities. OPTIONS TRANSACTIONS Writing Covered Call Options. The Fund may write (i.e., sell) covered call options. By writing a call option, the Fund becomes obligated during the term of the option to deliver the securities underlying the option upon payment of the exercise price. The Fund may only write "covered" options. This means that, so long as the Fund is obligated as the writer of a call option, it will own the underlying securities subject to the option or, in the case of call options on U.S. Treasury bills, the Fund might own substantially similar U.S. Treasury bills. The principal reason for writing call options is to obtain, through a receipt of premiums, a greater current return than would be realized on the underlying securities alone. The Fund receives a premium for writing a call option, which it retains whether or not the option is exercised. By writing a call option, the Fund might lose the potential for gain on the underlying security while the option is open. Purchasing Options. The Fund may purchase call options for the purpose of offsetting previously written call options of the same series. If the Fund is unable to effect a closing purchase transaction with respect to covered options it has written, the Fund will not be able to sell the underlying securities or dispose of assets held in a segregated account until the options expire or are exercised. An option position may be closed out only in a secondary market for an option of the same series. Although the Fund generally will write only those options for which there appears to be an active secondary market, there is no assurance that a liquid secondary market will exist for any particular option at any particular time, and, for some options, no secondary market may exist. In such event, it might not be possible to effect a closing transaction in a particular option. (iii)

Options on some securities are relatively new, and it is impossible to predict the amount of trading interest that will exist in such options. There can be no assurance that viable markets will develop or continue. The failure of such markets to develop or continue could significantly impair the Fund's ability to use such options to achieve its investment objective. OPTIONS TRADING MARKETS Options in which the Fund will trade are generally listed on national securities exchanges. Exchanges on which such options currently are traded include the Chicago Board Options Exchange and the New York, American, Pacific and Philadelphia Stock Exchanges. Options on some securities may not be listed on any exchange, but traded in the over-the-counter market. Options traded in the over-the-counter market involve the additional risk that securities dealers participating in such transactions could fail to meet their obligations to the Fund. The use of options traded in the over-the-counter market may be subject to limitations imposed by certain state securities authorities. In addition to the limits on its use of options discussed herein, the Fund is subject to the investment restrictions described in this prospectus and in the statement of additional information. The staff of the Securities and Exchange Commission is of the view that the premiums that a Fund pays for the purchase of unlisted options and the value of securities used to cover unlisted options written by the Fund are considered to be invested in illiquid securities or assets for the purpose of calculating whether the Fund is in compliance with its investment restrictions relating to illiquid securities. FUTURES TRANSACTIONS The Fund may enter into currency and other financial futures contracts and write options on such contracts. The Fund intends to enter into such contracts and related options for hedging purposes. The Fund will enter into securities, currencies or index-based futures contracts in order to hedge against changes in interest or exchange rates or securities prices. A futures contract on securities or currencies is an agreement to buy or sell securities or currencies at a specified price during a designated month. A futures contract on a securities index does not involve the actual delivery of securities, but merely requires the payment of a cash settlement based on changes in the securities index. The Fund does not make payment or deliver securities upon entering into a futures contract. Instead, it puts down a margin deposit, which is adjusted to reflect changes in the value of the contract and which continues until the contract is terminated. The Fund may sell or purchase currency and other financial futures contracts. When a futures contract is sold by the Fund, the value of the contract will tend to rise when the value of the underlying securities or currencies declines and to fall when the value of such securities or currencies increases. Thus, the Fund sells futures contracts in order to offset a possible decline in the value of its securities or currencies. If a futures contract is purchased by the Fund, the value of the contract will tend to rise when the value of the underlying securities or currencies increases and to fall when the value of such securities or currencies declines. The Fund intends to purchase futures contracts in order to fix what is believed by Keystone to be a favorable price and rate of return for securities or favorable exchange rate for currencies the Fund intends to purchase. The Fund also intends to purchase put and call options on currency and other financial futures contracts for hedging purposes. A put option purchased by the Fund would give it the right to assume a position as the seller of a futures contract. A call option purchased by the Fund would give it the right to assume a position as the purchaser of a futures contract. The purchase of an option on a futures contract requires the Fund to pay a premium. In exchange for the premium, the Fund becomes entitled to exercise the benefits, if any, provided by the futures contract, but is not required to take any action under the contract. (iv)

If the option cannot be exercised profitably before it expires, the Fund's loss will be limited to the amount of the premium and any transaction costs. The Fund may enter into closing purchase and sale transactions in order to terminate a futures contract and may sell put and call options for the purpose of closing out its options positions. The Fund's ability to enter into closing transactions depends on the development and maintenance of a liquid secondary market. There is no assurance that a liquid secondary market will exist for any particular contract or at any particular time. As a result, there can be no assurance that the Fund will be able to enter into an offsetting transaction with respect to a particular contract at a particular time. If the Fund is not able to enter into an offsetting transaction, the Fund will continue to be required to maintain the margin deposits on the contract and to complete the contract according to its terms, in which case, it would continue to bear market risk on the transaction. Although futures and options transactions are intended to enable the Fund to manage market, interest rate or exchange rate risk, unanticipated changes in interest rates, exchange rates or market prices could result in poorer performance than if it had not entered into these transactions. Even if Keystone correctly predicts interest or exchange rate movements, a hedge could be unsuccessful if changes in the value of the Fund's futures position did not correspond to changes in the value of its investments. This lack of correlation between the Fund's futures and securities or currencies positions may be caused by differences between the futures and securities or currencies markets or by differences between the securities or currencies underlying the Fund's futures position and the securities or currencies held by or to be purchased for the Fund. Keystone will attempt to minimize these risks through careful selection and monitoring of the Fund's futures and options positions. The Fund does not intend to use futures transactions for speculation or leverage. The Fund has the ability to write options on futures, but intends to write such options only to close out options purchased by the Fund. The Fund will not change these policies without supplementing the information in its prospectus and statement of additional information. FOREIGN CURRENCY TRANSACTIONS As discussed above, the Fund may invest in securities of foreign issuers. When the Fund invests in foreign securities, they usually will be denominated in foreign currencies, and the Fund temporarily may hold funds in foreign currencies. Thus, the value of Fund shares will be affected by changes in exchange rates. As one way of managing exchange rate risk, in addition to entering into currency futures contracts, the Fund may enter into forward currency exchange contracts (agreements to purchase or sell currencies at a specified price and date). The exchange rate for the transaction (the amount of currency the Fund will deliver or receive when the contract is completed) is fixed when the Fund enters into the contract. The Fund usually will enter into these contracts to stabilize the U.S. dollar value of a security it has agreed to buy or sell. The Fund intends to use these contracts to hedge the U.S. dollar value of a security it already owns, particularly if the Fund expects a decrease in the value of the currency in which the foreign security is denominated. Although the Fund will attempt to benefit from using forward contracts, the success of its hedging strategy will depend on Keystone's ability to predict accurately the future exchange rates between foreign currencies and the U.S. dollar. The value of the Fund's investments denominated in foreign currencies will depend on the relative strength of those currencies and the U.S. dollar, and the Fund may be affected favorably or unfavorably by changes in the exchange rates or exchange control regulations between foreign currencies and the dollar. Changes in foreign currency exchange rates also may affect the value of dividends and interest earned, gains and losses realized on the sale of securities and net investment (v)

income and gains, if any, to be distributed to shareholders by the Fund. Although the Fund does not currently intend to do so, the Fund may also purchase and sell options related to foreign currencies. The Fund does not intend to enter into foreign currency transactions for speculation or leverage. LOANS OF SECURITIES TO BROKER-DEALERS The Fund may lend securities to brokers and dealers pursuant to agreements requiring that the loans be continuously secured by cash or securities of the U.S. government, its agencies or instrumentalities or any combination of cash and such securities, as collateral equal at all times in value to at least the market value of the securities loaned. Such securities loans will not be made with respect to the Fund if, as a result, the aggregate of all outstanding securities loans exceeds 15% of the value of the Fund's total assets taken at their current value. The Fund continues to receive interest or dividends on the securities loaned and simultaneously earns interest on the investment of the cash loan collateral in U.S. Treasury notes, certificates of deposit, other high-grade, short-term obligations or interest bearing cash equivalents. Although voting rights attendant to securities loaned pass to the borrower, such loans may be called at any time and will be called so that the securities may be voted by the Fund if, in the opinion of the Fund, a material event affecting the investment is to occur. There may be risks of delay in receiving additional collateral or in recovering the securities loaned or even loss of rights in the collateral should the borrower of the securities fail financially. Loans may only be made, however, to borrowers deemed to be of good standing, under standards approved by the Board of Trustees, when the income to be earned from the loan justifies the attendant risks. (vi)

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