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012 B000001 84-1817
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012 C030001 80231
013 A000001 COOPERS & LYBRAND L.L.P.
013 B010001 SPRINGFIELD
013 B020001 MA
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015 A000001 THE CHASE MANHATTAN BANK, N.A.
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<PAGE> PAGE 2
015 C010001 BROOKLYN
015 C020001 NY
015 C030001 11245
015 E010001 X
018 000000 Y
019 A000000 Y
019 B000000 32
019 C000000 MASSMUTUAL
020 A000001 JONES & ASSOCIATES, INC.
020 B000001 95-3583143
020 C000001 17
020 A000002 LEGG MASON WOOD WALKER, INC.
020 B000002 52-0902557
020 C000002 15
020 A000003 DONALDSON, LUFKIN, JENRETTE SECURITIES CORP.
020 B000003 13-2741729
020 C000003 11
020 A000004 ALLEN & COMPANY INCORPORATED
020 B000004 13-6176976
020 C000004 6
020 A000005 JANNEY MONTGOMERY SCOTT INC.
020 B000005 23-0731260
020 C000005 3
020 A000006 ADVEST, INC.
020 B000006 06-0950348
020 C000006 2
020 A000007 MERRILL LYNCH PIERCE FENNER & SMITH, INC.
020 B000007 13-5674085
020 C000007 2
020 A000008 MCMAHAN SECURITIES CO., L.P.
020 B000008 06-1229141
020 C000008 1
020 A000009 SMITH BARNEY, INC.
020 B000009 13-1912900
020 C000009 1
020 A000010 GOLDMAN, SACHS & CO.
020 B000010 13-5108880
020 C000010 1
021 000000 57
022 A000001 MERRILL LYNCH, PIERCE, FENNER & SMITH, INC.
022 B000001 13-5674085
022 C000001 149557
022 D000001 13394
022 A000002 GOLDMAN, SACHS & CO.
022 B000002 13-5108880
022 C000002 90423
022 D000002 4607
022 A000003 LEHMAN BROTHERS, INC.
022 B000003 13-2518466
022 C000003 43764
022 D000003 4582
<PAGE> PAGE 3
022 A000004 DONALDSON, LUFKIN & JENRETTE SECURITIES CORP.
022 B000004 13-2741729
022 C000004 6516
022 D000004 10007
022 A000005 JEFFERIES & COMPANY
022 B000005 95-2622900
022 C000005 7707
022 D000005 6399
022 A000006 MORGAN (J.P.) SECURITIES INC..
022 B000006 13-3224016
022 C000006 11010
022 D000006 1624
022 A000007 MORGAN STANLEY AND CO.
022 B000007 13-2655998
022 C000007 7654
022 D000007 3660
022 A000008 BA SECURITIES, INC.
022 B000008 95-4035346
022 C000008 8909
022 D000008 642
022 A000009 GRANTCHESTER SECURITIES, INC.
022 B000009 13-3502273
022 C000009 1746
022 D000009 3311
022 A000010 BT SECURITIES, INC.
022 B000010 13-3311934
022 C000010 2370
022 D000010 2576
023 C000000 361298
023 D000000 71672
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<PAGE> PAGE 5
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<PAGE> PAGE 8
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SIGNATURE STEPHEN L. KUHN
TITLE SECRETARY
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THE SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
REPORT TO SHAREHOLDERS OF MASSMTUUAL CORPORATE INVESTORS FOR THE YEAR
ENDED DECEMBER 31, 1997 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000275694
<NAME> MASSMUTUAL CORPORATE INVESTORS
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1997
<PERIOD-START> JAN-01-1997
<PERIOD-END> DEC-31-1997
<INVESTMENTS-AT-COST> 210,173,084
<INVESTMENTS-AT-VALUE> 226,086,536
<RECEIVABLES> 3,730,101
<ASSETS-OTHER> 80,311
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 229,896,948
<PAYABLE-FOR-SECURITIES> 150,000
<SENIOR-LONG-TERM-DEBT> 20,000,000
<OTHER-ITEMS-LIABILITIES> 16,888,530
<TOTAL-LIABILITIES> 37,038,530
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 102,847,441
<SHARES-COMMON-STOCK> 8,513,448
<SHARES-COMMON-PRIOR> 8,513,448
<ACCUMULATED-NII-CURRENT> 586,318
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 16,063,664
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 15,913,452
<NET-ASSETS> 192,858,418
<DIVIDEND-INCOME> 644,690
<INTEREST-INCOME> 16,289,353
<OTHER-INCOME> 0
<EXPENSES-NET> 4,274,715
<NET-INVESTMENT-INCOME> 12,659,328
<REALIZED-GAINS-CURRENT> 20,531,522
<APPREC-INCREASE-CURRENT> 3,957,012
<NET-CHANGE-FROM-OPS> 24,488,534
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 12,090,799
<DISTRIBUTIONS-OF-GAINS> 4,467,858
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 0
<NUMBER-OF-SHARES-REDEEMED> 0
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 20,589,205
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 57,447,543
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2,904,066
<INTEREST-EXPENSE> 1,066,000
<GROSS-EXPENSE> 4,274,715
<AVERAGE-NET-ASSETS> 190,071,380
<PER-SHARE-NAV-BEGIN> 20.23
<PER-SHARE-NII> 1.49
<PER-SHARE-GAIN-APPREC> 2.87
<PER-SHARE-DIVIDEND> 1.42
<PER-SHARE-DISTRIBUTIONS> 0.52
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 22.65
<EXPENSE-RATIO> 0.666
<AVG-DEBT-OUTSTANDING> 20,000,000
<AVG-DEBT-PER-SHARE> 2.35
</TABLE>
EXHIBIT INDEX TO FORM N-SAR
OF MASSMUTUAL CORPORATE INVESTORS
FOR PERIOD ENDED DECEMBER 31, 1997
EXHIBIT NO. DESCRIPTION
77B Accountant's Report on Internal Control
77O Transactions Effected Pursuant to Rule 10f-3
Item 77B
Coopers Coopers & Lybrand L.L.P.
& Lybrand a professional services firm
To the Board of Trustees of
MassMutual Corporate Investors:
In planning and performing our audit of the financial statements of MassMutual
Corporate Investors for the year ended December 31, 1997, we considered its
internal control, including controls over safeguarding securities, in order to
determine our auditing procedures for the purpose of expressing our opinion on
the financial statements and to comply with the requirements of Form N-SAR,
not to provide assurance on internal control.
The management of MassMutual Corporate Investors is responsible for
establishing and maintaining internal control. In fulfilling this
responsibility, estimates and judgments by management are required to assess
the expected benefits and related costs of controls. Generally, controls that
are relevant to an audit pertain to the entity's objective of preparing
financial statements for external purposes that are fairly presented in
conformity with generally accepted accounting principles. Those controls
include the safeguarding of assets against unauthorized acquisition, use or
disposition.
Because of inherent limitations in internal control, errors or irregularities
may occur and may not be detected. Also, projection of any evaluation of
internal control to future periods is subject to the risk that it may become
inadequate because of changes in conditions or that the effectiveness of the
design and operation may deteriorate.
Our consideration of internal control would not necessarily disclose all
matters in internal control that might be material weaknesses under standards
established by the American Institute of Certified Public Accountants. A
material weakness is a condition in which the design or operation of any
specific internal control component does not reduce to a relatively low level
the risk that errors or irregularities in amounts that would be material in
relation to the financial statements being audited may occur and not be
detected within a timely period by employees in the normal course of
performing their assigned functions. However, we noted no matters involving
internal control, including controls over safeguarding securities, that we
consider to be material weaknesses as defined above as of December 31, 1997.
This report is intended solely for the information and use of management and
the Securities and Exchange Commission.
COOPERS & LYBRAND L.L.P.
Springfield, Massachusetts
January 30, 1998
Coopers & Lybrand L.L.P. is a member of Coopers & Lybrand International, a
limited liability association incorporated in Switzerland.
For Period Ending 12/31/97
File No. 811-2183
Item 77O. Transactions Effected Pursuant to Rule 10f-3
Registrant purchased in a Rule 144A offering from Jefferies & Co., Inc.
700 shares of 13.25% Preferred Stock issued by Jordan Telecomm Products, Inc.
at a price of $100.00 per share on July 22, 1997. 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
provisions of Rule 10f-3 promulgated under the Act. Registrant's Board of
Trustees have adopted the procedures, pursuant to which such purchases may be
effected. Such procedures are reasonably designed to provide for the
conditions set forth in subsections (a) through (g) of Rule 10f-3.
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.
