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 19, 2018

W. R. BERKLEY CORPORATION

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (203) 629-3000

Not Applicable

(Former name or former address, if changed since last report)

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

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 1.01 Entry into a Material Definitive Agreement.

On March 19, 2018, W. R. Berkley Corporation (the “Company”) agreed to sell $175.00 million aggregate principal amount of its 5.70% Subordinated Debentures due 2058 (the “Securities”). The Securities were offered pursuant to the Prospectus Supplement dated March 19, 2018 (the “Prospectus Supplement”) to the Prospectus dated November 14, 2017, filed as part of the Registration Statement on Form S-3 (No. 333-221559) that became effective when filed with the Securities and Exchange Commission on November 14, 2017. The offering is expected to close on March 26, 2018, subject to customary closing conditions. In addition, the Company has granted the underwriters an option, exercisable for 30 days from the date of the Prospectus Supplement, to purchase up to an additional $26.25 million aggregate principal amount of the Securities solely to cover overallotments, if any.

On March 19, 2018, the Company entered into an underwriting agreement with Morgan Stanley & Co. LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated, UBS Securities LLC and Wells Fargo Securities, LLC, as representatives of the several underwriters named therein, with respect to the offer and sale of the Securities. A copy of the Underwriting Agreement is attached as Exhibit 1.1 hereto.

On March 19, 2018, Willkie Farr & Gallagher LLP, tax counsel to the Company, issued an opinion and consent (attached hereto as Exhibits 8.1 and 23.1, respectively, and incorporated herein by reference) regarding certain U.S. Federal income tax matters in connection with the Securities.

Item 9.01 Financial Statements and Exhibits.

The exhibits to this report are incorporated by reference into Registration Statement (No. 333-221559) filed by the Company.

(d) Exhibits

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EXHIBIT INDEX

Exhibit:

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.

Date: March 20, 2018