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<PAGE> PAGE 2
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015 C030001 11245
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019 C000000 MASSMUTUAL
020 A000001 DONALDSON, LUFKIN & JENRETTE SECURITIES CORP.
020 B000001 13-2741729
020 C000001 10
020 A000002 JONES & ASSCOCIATES INC
020 B000002 95-3583143
020 C000002 8
020 A000003 ALLEN & COMPANY INCORPORATED
020 B000003 13-6176976
020 C000003 8
020 A000004 HAMBRECHT & QUIST LLC
020 B000004 94-3220292
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020 A000005 DAIN RAUSCHER INCORPORATED
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020 A000006 LAZARD FRERES & CO. LLC
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020 A000007 LEGG MASON WOOD WALKER, INC.
020 B000007 52-0902557
020 C000007 3
020 A000008 MERRILL LYNCH, PIERCE FENNER & SMITH INC.
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020 C000008 1
020 A000009 JANNEY MONTGOMERY SCOTT INC.
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022 A000001 GOLDMAN, SACHS & CO
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022 C000002 52767
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022 A000003 LEHMAN BROTHERS, INC.
022 B000003 13-2518466
022 C000003 24519
022 D000003 1310
<PAGE> PAGE 3
022 A000004 MORGAN STANLEY & CO. INCORPORATED
022 B000004 13-2655998
022 C000004 8652
022 D000004 3734
022 A000005 BT ALEX. BROWN INCORPORATED
022 B000005 52-1319768
022 C000005 5849
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022 A000006 CHASE MANHATTAN
022 C000006 7322
022 D000006 0
022 A000007 MORGAN (J.P.) SECURITIES INC.
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022 A000008 DONALDSON, LUFKIN & JENRETTE SECURITIES CORP.
022 B000008 13-2711729
022 C000008 3155
022 D000008 2190
022 A000009 SALOMON SMITH BARNEY HOLDINGS INC.
022 C000009 3816
022 D000009 770
022 A000010 BA SECURITIES, INC.
022 B000010 04-2476032
022 C000010 4134
022 D000010 204
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<PAGE> PAGE 9
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SIGNATURE CHARLES C. MCCOBB
TITLE VICE PRESIDENT & CFO
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THE SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
REPORT TO SHAREHOLDERS OF MASSMUTUAL CORPORATE INVESTORS FOR THE SIX
MONTHS ENDED JUNE 30, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE
TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000275694
<NAME> MASSMUTUAL CORPORATE INVESTORS
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JAN-01-1998
<PERIOD-END> JUN-30-1998
<INVESTMENTS-AT-COST> 208,058,943
<INVESTMENTS-AT-VALUE> 232,884,598
<RECEIVABLES> 5,259,468
<ASSETS-OTHER> 443,837
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 238,587,903
<PAYABLE-FOR-SECURITIES> 1,965,152
<SENIOR-LONG-TERM-DEBT> 20,000,000
<OTHER-ITEMS-LIABILITIES> 1,017,188
<TOTAL-LIABILITIES> 22,982,340
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 104,213,373
<SHARES-COMMON-STOCK> 8,569,162
<SHARES-COMMON-PRIOR> 8,513,448
<ACCUMULATED-NII-CURRENT> 3,862,019
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 9,193,310
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 24,825,563
<NET-ASSETS> 215,605,563
<DIVIDEND-INCOME> 382,008
<INTEREST-INCOME> 8,602,363
<OTHER-INCOME> 0
<EXPENSES-NET> 2,288,043
<NET-INVESTMENT-INCOME> 6,696,328
<REALIZED-GAINS-CURRENT> 9,193,310
<APPREC-INCREASE-CURRENT> 8,912,203
<NET-CHANGE-FROM-OPS> 24,801,841
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 3,420,627
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 0
<NUMBER-OF-SHARES-REDEEMED> 0
<SHARES-REINVESTED> 55,714
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<ACCUMULATED-GAINS-PRIOR> 73,493,073
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 1,600,884
<INTEREST-EXPENSE> 533,000
<GROSS-EXPENSE> 2,288,043
<AVERAGE-NET-ASSETS> 204,289,554
<PER-SHARE-NAV-BEGIN> 22.65
<PER-SHARE-NII> 0.78
<PER-SHARE-GAIN-APPREC> 2.13
<PER-SHARE-DIVIDEND> (0.40)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 25.16
<EXPENSE-RATIO> 1.12
<AVG-DEBT-OUTSTANDING> 20,000,000
<AVG-DEBT-PER-SHARE> 2.33
</TABLE>
EXHIBIT INDEX TO FORM N-SAR
OF MASSMUTUAL CORPORATE INVESTORS
FOR PERIOD ENDED JUNE 30, 1998
EXHIBIT NO. DESCRIPTION
77O Transactions Effected Pursuant to Rule 10f-3
For Period Ending 06/30/98
File No. 811-2183
Item 77O. Transactions Effected Pursuant to Rule 10f-3
Registrant purchased in a Rule 144A offering from Jefferies & Co.,
Inc. $500,000 9.75% Senior Notes due 2006, Series C, issued by Parker
Drilling Company at a price of $103.833 on March 4, 1998. Mr. Richard
G. Dooley, Vice Chairman and member of the Board of Trustees of
Registrant, is a director of Jefferies Group, Inc., the parent of
Jefferies & Co.
To the extent such offerings might be deemed to be underwritten public
offerings, Registrant claims an exemption from the provisions of
Section 10(f) of the Investment Company Act of 1940, as amended, (the
"Act") on the basis that, with respect to this purchase, Registrant
has complied with the procedures adopted by Registrant's Board of
Trustees pursuant to the provisions of Rule 10f-3 promulgated under
the Act.
Registrant will preserve a record of this transaction for a period of
six years from the end of the fiscal year in which the transaction
occurred, the first two years in an easily accessible place.
