UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): March 11, 2013

VIACOM INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (212) 258-6000

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

Section 8 - Other Events

On March 11, 2013, Viacom Inc. (the “Company”) announced that it had agreed to issue and sell $300,000,000 aggregate principal amount of 3.250% Senior Notes due 2023 (the “Senior Notes”) and $250,000,000 aggregate principal amount of 4.875% Senior Debentures due 2043 (the “Senior Debentures” and, together with the Senior Notes, the “Securities”). In connection with the issuance and sale of the Securities, on March 11, 2013, the Company entered into an underwriting agreement (the “Underwriting Agreement”) with BNP Paribas Securities Corp., Goldman, Sachs & Co. and J.P. Morgan Securities LLC, as representatives of the underwriters named in Schedule 1 thereto. The offering is being made pursuant to the Company’s effective registration statement on Form S-3 (Registration Statement No. 333-184770) previously filed with the Securities and Exchange Commission (the “Registration Statement”). The foregoing description of the Underwriting Agreement is qualified in its entirety by reference to the text of the Underwriting Agreement, a copy of which is filed herewith as Exhibit 1.1.

On March 14, 2013, in connection with the closing of the sale of the Securities, the Company and The Bank of New York Mellon, as trustee (the “Trustee”), entered into a fifteenth supplemental indenture (the “Fifteenth Supplemental Indenture”) to the Indenture, dated as of April 12, 2006, between the Company and the Trustee. The Fifteenth Supplemental Indenture is filed as Exhibit 4.1 to this Report. A copy of the opinion of Shearman & Sterling LLP relating to the legality of the Securities is filed as Exhibit 5.1 to this Report.

The Company incorporates by reference the exhibits filed herewith into the Registration Statement, pursuant to which the Securities were registered.

Section 9 - Financial Statements and Exhibits

(d)        Exhibits.  The following exhibits are filed as part of this Report on Form 8-K:

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: March 14, 2013

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Exhibit Index

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