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EXHIBIT 14(a)
MERCURY INDEX FUNDS, INC.
PLAN PURSUANT TO RULE 18f-3 UNDER THE INVESTMENT COMPANY ACT
Each series of Mercury Index Funds, Inc. (individually a "Fund" and,
collectively, the "Funds")offers Class I Shares and Class A Shares as follows:
Account Maintenance Fees
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Class A Shares bear the expenses of the ongoing account maintenance fees
applicable to the Class A Shares.
Transfer Agency Expenses
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Each Class shall bear any incremental transfer agency cost applicable to the
particular class.
Voting Rights
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Class A Shares have exclusive voting rights on any matter submitted to
shareholders that relates solely to its account maintenance fees. Each Class
shall have separate voting rights on any matter submitted to shareholders in
which the interests of one Class differ from the interests of the other Class.
Dividends
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Dividends paid on each Class will be calculated in the same manner at the
same time and will differ only to the extent that any account maintenance fee
and any incremental transfer agency cost relates to a particular Class.
Exchange Privileges
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Holders of Class I Shares and Class A Shares shall have such exchange
privileges as set forth in the Funds' current prospectus and statement of
additional information. Exchange privileges may vary between Classes and among
holders of a Class.
Other Rights and Obligations
----------------------------
Except as otherwise described above, in all respects, each Class shall have
the same rights and obligations as the other Class.
