UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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): July 20, 2016

Belden Inc.

(EXACT NAME OF REGISTRANT AS SPECIFIED IN CHARTER)

1 North Brentwood Boulevard, 15^th Floor

St. Louis, Missouri 63105

(Address of Principal Executive Offices, including Zip Code)

(314) 854-8000

(Registrant’s telephone number, including area code)

n/a

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if this Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

On July 20, 2016, Belden Inc. (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) with J.P. Morgan Securities LLC and Guggenheim Securities, LLC, as representatives of the underwriters named on Schedule 1 thereto (the “Underwriters”), pursuant to which the Company agreed to issue and sell to the Underwriters an aggregate of 4,500,000 depositary shares (the “Depositary Shares”), each representing a 1/100th interest in a share of the Company’s 6.75% Series B Mandatory Convertible Preferred Stock, in a registered public offering (the “Offering”) pursuant to the Company’s automatic shelf registration statement (the “Registration Statement”) on Form S-3ASR filed with the Securities and Exchange Commission on May 31, 2016 (Registration No. 333-211717). The Company granted the Underwriters a 30-day option to purchase up to 675,000 additional Depositary Shares, at the public offering price, less the underwriting discount (the “Option”). On July 22, 2016, the Underwriters exercised the Option in full. The foregoing description of the terms and conditions of the Underwriting Agreement is qualified in its entirety by reference to the Underwriting Agreement, which is incorporated herein by reference and attached hereto as Exhibit 1.1.

In connection with the Offering described in Item 1.01 above, on July 26, 2016, the Company filed a Certificate of Designations (the “Certificate of Designations”) with the Secretary of State of the State of Delaware to establish the preferences, limitations and relative rights of its 6.75% Series B Mandatory Convertible Preferred Stock, liquidation preference $10,000.00 per share, par value $0.01 per share (the “Mandatory Convertible Preferred Stock”). The Certificate of Designations became effective upon filing.

Subject to certain exceptions, so long as any share of Mandatory Convertible Preferred Stock remains outstanding, no dividend or distribution will be declared or paid on the Company’s common stock or any other shares of junior stock, and no common stock or other junior stock or parity stock will be, directly or indirectly, purchased, redeemed or otherwise acquired for consideration by the Company or any of its subsidiaries unless all accumulated and unpaid dividends for all preceding dividend periods have been declared and paid upon, or a sufficient sum or number of shares of common stock have been set apart for the payment of such dividends upon, all outstanding shares of Mandatory Convertible Preferred Stock.

Unless converted earlier, each share of Mandatory Convertible Preferred Stock will convert automatically on the mandatory conversion date, which is expected to be July 15, 2019, into between 120.46 and 132.50 shares of the Company’s common stock, subject to customary anti-dilution adjustments. The number of shares of common stock issuable upon conversion will be determined based on the average volume weighted average price per share of the Company’s common stock over the 20 consecutive trading day period beginning on, and including, the 22nd scheduled trading day immediately preceding July 15, 2019.

In addition, upon the Company’s voluntary or involuntary liquidation, winding-up or dissolution, each holder of Mandatory Convertible Preferred Stock will be entitled to receive a liquidation preference of $10,000.00 per share of Mandatory Convertible Preferred Stock, plus an amount equal to accumulated and unpaid dividends on such shares to, but excluding, the date fixed for liquidation, winding-up or dissolution to be paid out of the assets of the Company available for distribution to its stockholders, after satisfaction of liabilities owed to the Company’s creditors and holders of any senior stock and before any payment or distribution is made to holders of any junior stock, including the Company’s common stock.

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The foregoing description of the terms of the Mandatory Convertible Preferred Stock, including such restrictions, is qualified in its entirety by reference to the Certificate of Designations, a copy of which is filed as Exhibit 3.1 hereto, and is incorporated herein by reference.

On July 26, 2016, the Company filed the Certificate of Designations with the Secretary of State of the State of Delaware to establish the preferences, limitations and relative rights of the Mandatory Convertible Preferred Stock. The Certificate of Designations became effective upon filing, and a copy is filed as Exhibit 3.1 hereto, and is incorporated herein by reference.

(d) Exhibits.

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SIGNATURES

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.

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EXHIBIT INDEX

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