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                                  UNITED STATES
                        SECURITIES AND EXHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                                  SCHEDULE 13G

                    UNDER THE SECURITIES EXCHANGE ACT OF 1934
                               (AMENDMENT NO. 3)*

                         MassMutual Participation Investors
                                (NAME OF ISSUER)


                                  Common Shares
                         (TITLE OF CLASS OF SECURITIES)


                                    576299101
                                 (CUSIP NUMBER)


                               December 31, 2008
             (DATE OF EVENT WHICH REQUIRES FILING OF THIS STATEMENT)

         Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:

         [X] Rule 13d-1(b)

         [ ] Rule 13d-1(c)

         [ ] Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).
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CUSIP No. 576299101                    13G                     PAGE 2 OF 6 PAGES
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  1   NAMES OF REPORTING PERSONS:

      Massachusetts Mutual Life Insurance Company
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  2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                         (a) [_]
                                                                         (b) [_]
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  3   SEC USE ONLY


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  4   CITIZENSHIP OR PLACE OF ORGANIZATION

      Commonwealth of Massachusetts
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                            5   SOLE VOTING POWER

                                1,386,268
       NUMBER OF          ----- ------------------------------------------------
         SHARES             6   SHARED VOTING POWER
      BENEFICIALLY
        OWNED BY                0
          EACH            ----- ------------------------------------------------
       REPORTING            7   SOLE DISPOSITIVE POWER
         PERSON
          WITH                  1,386,268
                          ----- ------------------------------------------------
                            8   SHARED DISPOSITIVE POWER

                                0
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  9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

      1,386,268

      Massachusetts Mutual Life Insurance Company holds a $12,000,000 Senior
      Fixed Rate Convertible Note that is convertible into an equivalent dollar
      amount of common shares.
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 10   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES  [X]


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 11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

      12.30%

      The conversion rate of the Senior Fixed Rate Convertible Note is based on
      the market price of MassMutual Participation Investor's  common shares, so
      Massachusetts Mutual Life Insurance Company's beneficial ownership may be
      slightly greater than or less than 10% at the end of any given month.
----- --------------------------------------------------------------------------
 12   TYPE OF REPORTING PERSON

      IC
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CUSIP No. 576299101                    13G                     PAGE 3 OF 6 PAGES
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Item     1(a) Name of Issuer:

              MassMutual Corporate Investors

         1(b) Address of Issuer's Principal Executive Offices:

              1500 Main Street
              Springfield, MA  01115

Item     2(a) Name of Person Filing:

              Massachusetts Mutual Life Insurance Company

         2(b) Address of Principal Business Office or, if None, Residence:

              Massachusetts Mutual Life Insurance Company
              1295 State Street
              Springfield, MA  01111

         2(c) Citizenship:

              Commonwealth of Massachusetts

         2(d) Title of Class of Securities:

              Common Shares

         2(e) CUSIP Number:

              576299101

Item     3    This statement is filed pursuant to Rule 13d-1(b) by Massachusetts
              Mutual Life Insurance Company, an insurance company as defined in
              Section 3(a)(19) of the Securities Exchange Act of 1934.

Item     4    Ownership

         4(a) Amount beneficially owned:

              Massachusetts Mutual Life Insurance Company ("MassMutual") is the
	      holder of a $12,000,000 MassMutual Participation Investors ("MMPI")
              Senior Fixed Rate Convertible Note (the "Note") issued by the
	      Trust in 1995 due December 13, 2011. The dollar amount
              of principal of the Note is convertible into an equivalent
              dollar amount of MMPI's common shares based upon the average
              price of MMPI's common shares for ten business days prior to
              MassMutual's notice of conversion. The ten business day average
              closing market price of MMPI's common shares for


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CUSIP No. 576299101                    13G                     PAGE 4 OF 6 PAGES
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              the ten-day period ended December 31, 2008 was $8.89 and as such
              the Note would have converted into approximately 1,349,831
              common shares if the Note had been converted as of December
              31, 2008. Since the conversion rate is based on the market price
	      of MMPI's common shares, MassMutual's beneficial ownership may be
              slightly greater than or less than 10% at the end of any given
              month.  Additionally, MassMutual owns 36,437 common shares
              of MMPI.

              Total shares of common shares owned directly and indirectly:
              1,386,268 (subject to change with market). Additionally,
              Babson Capital Management LLC, a wholly-owned indirect subsidiary
	      of MassMutual, is the beneficial owner of 143,404 common
	      shares of MMPI.


              The filing of this statement shall not be construed as an
              admission that MassMutual is for the purpose of Sections 13(d)
              and 13(g) of the Securities Exchange Act of 1934, the beneficial
              owner of any of the common shares stock of MMPI, including the
              common shares held by Babson Capital Management LLC.

         4(b) Percent of Class:

              The 1,386,268 common shares mentioned above represent 12.30% of
	      MMPI's common shares calculated as follows:

       1,386,268 (common shares from conversion based on a conversion price
       of $8.89 + outstanding common shares owned) / 1,349,831 (number of new
       common shares that would be issued by MMPI upon conversion) + 9,927,243
      (common shares outstanding as of December 31, 2008) = 12.30%

              Since the conversion rate is based on the market price of MMPI's
              common shares, MassMutual's beneficial ownership may be slightly
              greater than or less than 10% at the end of any given month.

         4(c) Number of shares as to which such person has:

              (i) sole power to vote or to direct the vote: 1,386,268  (subject
                  to change with market)

              (ii) shared power to vote or to direct the vote: 0

              (iii) sole power to dispose or to direct the disposition of:
                    1,386,268  (subject to change with market)

              (iv) shared power to dispose or to direct the disposition of: 0

Item     5    Ownership of Five Percent or Less of a Class:

              Not applicable


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CUSIP No. 576299101                     13G                    PAGE 5 OF 6 PAGES
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Item 6   Ownership of More than Five Percent on Behalf of Another Person:

         Not applicable

Item 7   Identification and Classification of the Subsidiary which Acquired the
         Security Being Reported on by the Parent Holding Company:

         Not applicable

Item 8   Identification and Classification of Members of the Group:

         Not applicable

Item 9   Notice of Dissolution of Group:

         Not applicable

Item 10  Certifications:

         By signing below MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY certifies
that, to the best of its knowledge and belief, the security referred to above
was acquired and is held in the ordinary course of business and was not acquired
and is not held for the purpose of or with the effect of changing or influencing
the control of the issuer of the securities and was not acquired and is not held
in connection with or as a participant in any transaction having that purpose or
effect.


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CUSIP No. 576299101                    13G                     PAGE 6 OF 6 PAGES
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                                    SIGNATURE

         After reasonable inquiry and to the best of its knowledge and belief,
MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY certifies that the information set
forth in this statement is true, complete, and correct.

February 13, 2009


MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY

By: /s/ Christopher A. DeFrancis
    ---------------------------
Name: Christopher A. DeFrancis
Title: Vice President and Associate General Counsel