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      PAGE  2
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      PAGE  3
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      PAGE  4
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      PAGE  5
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      PAGE  6
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      PAGE  7
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      PAGE  8
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      PAGE  9
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SIGNATURE   JAMES M. ROY
TITLE       V.P. AND C.F.O.

                           EXHIBIT INDEX TO FORM N-SAR
                        OF MASSMUTUAL CORPORATE INVESTORS
                   FOR SEMI-ANNUAL PERIOD ENDED JUNE 30, 2011


EXHIBIT NO.                   DESCRIPTION

77O               Transactions Effected Pursuant to Rule 10f-3