EXHIBIT 99.4
 
                                                                  EXECUTION COPY
 
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                           VIACOM INTERNATIONAL INC.,
                                     ISSUER
 
                                      AND
 
                      VIACOM INTERNATIONAL SERVICES INC.,
                                   SUCCESSOR
 
                                      AND
 
                             THE BANK OF NEW YORK,
                                    TRUSTEE
 
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                         FOURTH SUPPLEMENTAL INDENTURE
 
                           DATED AS OF JULY 22, 1996
                      TO BE EFFECTIVE AS OF JULY 31, 1996
 
                    SUPPLEMENTING AND AMENDING THE INDENTURE
                          DATED AS OF OCTOBER 9, 1986
 
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                               SENIOR SECURITIES
 
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  FOURTH 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 BANK OF NEW YORK, a New York banking
corporation organized and existing under the laws of the United States (the
"Trustee"), as Trustee to the Indenture, dated as of October 9, 1986, as
supplemented by the First Supplement thereto, dated as of August 13, 1992, the
Second Supplement thereto, dated as of June 30, 1993 and the Third 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 $250 million principal amount of 7 1/2% Senior
Notes due 2002, $250 million principal amount of 8 1/4% Senior Notes due 2022,
$150 million principal amount of 5 7/8% Senior Notes due 2000 and $150 million
principal amount of 7 1/2% Senior Notes due 2023 (collectively, the
"Securities");
 
  WHEREAS, the Company and the Successor are parties to an Implementation
Agreement dated as of July 24, 1995 (the "Implementation Agreement") pursuant
to which, subject to the terms and conditions stated therein, the Company
shall convey substantially all of its assets to the Successor (the "Conveyance
of Assets") and the Successor shall assume substantially all of the
liabilities of the Company, including liabilities in respect of the Securities
(the "Assumption of Liabilities");
 
  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 10.01 of the Indenture;
 
  WHEREAS, the Successor is a corporation validly existing under the laws of
the State of Delaware;
 
  WHEREAS, the Successor has duly authorized the execution and delivery of
this Fourth Supplemental Indenture to assume all the obligations of the
Company under the Securities and the Indenture; and
 
  WHEREAS, immediately after the consummation of the Conveyance of the Assets
and the Assumption of Liabilities in accordance with the Implementation
Agreement, no Event of Default (as defined in the Indenture) and no event
which, after notice (or acquisition of knowledge) or lapse of time, or both,
would become an Event of Default, has happened and is continuing.
 
  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. From and after the consummation of the Conveyance of Assets and
the Assumption of Liabilities, the Successor hereby assumes all the
obligations of the Company under the Securities and the Indenture; 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 Fourth Supplemental Indenture is executed by the Company,
the Successor and the Trustee pursuant to the provisions of Sections 10.01 and
11.01(a) 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
Fourth Supplemental Indenture shall be read, taken and construed as one and
the same instrument. The Indenture, as supplemented and amended by this Fourth
Supplemental Indenture, is in all respects hereby adopted, ratified and
confirmed. All capitalized terms not defined in this Fourth Supplemental
Indenture shall have the meanings set forth in the Indenture.
 
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  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 Broadway
                                          New York, NY 10036
                                          Attention: Chief Financial Officer,
                                                  with a copy to the Office of
                                                  the General Counsel
 
  SECTION B.3. THE LAWS OF THE STATE OF NEW YORK SHALL GOVERN THIS FOURTH
SUPPLEMENTAL INDENTURE.
 
  SECTION B.4. This Fourth 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 Fourth
Supplemental Indenture or the due authorization and execution thereof by the
Company and the Successor, respectively.
 
  IN WITNESS WHEREOF, the parties have caused this Fourth 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 BANK OF NEW YORK
 
                                                     /s/ Mary LaGumina
                                          By___________________________________
                                            Name: Mary LaGumina
                                              Title: Assistant Vice President
 
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