EXHIBIT 99.6
 
                                                                  EXECUTION COPY
 
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                           VIACOM INTERNATIONAL INC.,
                                     ISSUER
 
                                      AND
 
                      VIACOM INTERNATIONAL SERVICES INC.,
                                   SUCCESSOR
 
                                      AND
 
                           THE CHASE MANHATTAN BANK,
                                    TRUSTEE
 
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                             SUPPLEMENTAL INDENTURE
 
                           DATED AS OF JULY 22, 1996
                      TO BE EFFECTIVE AS OF JULY 31, 1996
 
                    SUPPLEMENTING AND AMENDING THE INDENTURE
                          DATED AS OF APRIL 15, 1973,
                 AS SUPPLEMENTED BY THE SUPPLEMENTAL INDENTURE
                          DATED AS OF JANUARY 3, 1995
 
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                      7% SUBORDINATED DEBENTURES SERIES B
                                DUE JULY 1, 2003
 
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  SUPPLEMENTAL INDENTURE, dated as of July 22, 1996, to be effective as of
July 31, 1996, among VIACOM INTERNATIONAL INC., a corporation duly organized
and existing under the laws of the State of Delaware (as successor to
Paramount Communications Inc.) (the "Company"), VIACOM INTERNATIONAL SERVICES
INC. (the "Successor") and THE CHASE MANHATTAN BANK, a banking corporation
organized and existing under the laws of the State of New York (the
"Trustee"), as Trustee to the Indenture, dated as of April 15, 1973, as
supplemented by the Supplement thereto, dated as of January 3, 1995, between
the Company and the Trustee (as amended, the "Indenture").
 
                                   RECITALS
 
  WHEREAS, the Company and the Trustee are parties to the Indenture, pursuant
to which the Company has issued the 7% Subordinated Debentures Series B due
2003, the ("Securities");
 
  WHEREAS, the Company and the Successor are parties to an Implementation
Agreement dated as of July 24, 1995 pursuant to which, subject to the terms
and conditions stated therein, the Company shall convey substantially all of
its assets to the Successor and the Successor shall assume substantially all
of the liabilities of the Company, including liabilities in respect of the
Securities; and
 
  WHEREAS, the Company and the Successor desire, pursuant to Section 11.01 of
the Indenture, to supplement and amend the Indenture, in order to comply with
Section 12.01 of the Indenture.
 
  NOW, THEREFORE, in consideration of the premises, the Company, the Successor
and the Trustee covenant and agree with each other as follows:
 
                                   ARTICLE A
 
  SECTION A.1. The Successor hereby assumes all the covenants, agreements and
obligations of the Company under the Securities and the Indenture, including
the due and punctual payment of the principal of and interest on the
Securities; the Successor shall succeed to, and be substituted for, and may
exercise every right and power of, the Company under the Indenture with the
same effect as if the Successor had been named as the Company therein; and the
Company shall be relieved of all obligations and covenants under the
Securities and the Indenture.
 
                                   ARTICLE B
 
                           MISCELLANEOUS PROVISIONS
 
  SECTION B.1. This Supplemental Indenture is executed by the Company, the
Successor and the Trustee pursuant to the provisions of Section 11.01(a) and
12.01 of the Indenture, and the terms and conditions hereof shall be deemed to
be part of the Indenture for all purposes, so that the Indenture and this
Supplemental Indenture shall be read, taken and construed as one and the same
instrument. The Indenture, as supplemented and amended by this Supplemental
Indenture, is in all respects hereby adopted, ratified and confirmed. All
capitalized terms not defined in this Supplemental Indenture shall have the
meanings set forth in the Indenture.
 
  SECTION B.2. Any notice or communication by the Trustee to the Successor is
duly given if in writing and delivered in person or mailed by first-class mail
to the address set forth below:
 
                                   Viacom International Services Inc.1515
                                   BroadwayNew York, NY 10036Attention: Chief
                                   Financial Officer, with a copy to
the Office of the General Counsel
 
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  SECTION B.3. THE LAWS OF THE STATE OF NEW YORK SHALL GOVERN THIS
SUPPLEMENTAL INDENTURE.
 
  SECTION B.4. This Supplemental Indenture may be executed in any number of
counterparts, each of which when so executed shall be deemed to be an
original, but such counterparts shall together constitute but one and the same
instrument.
 
  SECTION B.5. The Trustee assumes no responsibility for the correctness of
the recitals herein contained, which shall be taken as the statements of the
Company and the Successor. The Trustee makes no representations and shall have
no responsibility as to the validity or sufficiency of this Supplemental
Indenture or the due authorization and execution thereof by the Company and
the Successor, respectively.
 
  IN WITNESS WHEREOF, the parties have caused this Supplemental Indenture to
be duly executed as of the day and year first written above.
 
                                          VIACOM INTERNATIONAL INC.
 
                                                  /s/ Michael D. Fricklas
                                          By___________________________________
                                                 Name: Michael D. Fricklas
                                               Title: Senior Vice President
                                            Deputy General Counsel
 
                                          VIACOM INTERNATIONAL SERVICES INC.
 
                                                  /s/ Michael D. Fricklas
                                          By___________________________________
                                                 Name: Michael D. Fricklas
                                               Title: Senior Vice President
                                            Deputy General Counsel
 
                                          THE CHASE MANHATTAN BANK
 
                                                    /s/ Ronald J. Halleran
                                          By___________________________________
                                            Name: Ronald J. Halleran
                                                Title: Second Vice President
 
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