# EDGAR Filing Document

**Accession Number:** 0000011544
**File Stem:** 0001193125-25-308800
**Filing Date:** 2025-12
**Character Count:** 8543
**Document Hash:** 020b8942657eda5f260671660754bc03
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-308800.hdr.sgml**: 20251205

**ACCESSION NUMBER**: 0001193125-25-308800

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 14

**CONFORMED PERIOD OF REPORT**: 20251205

**ITEM INFORMATION**: Other Events

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20251205

**DATE AS OF CHANGE**: 20251205

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** BERKLEY W R CORP
- **CENTRAL INDEX KEY:** 0000011544
- **STANDARD INDUSTRIAL CLASSIFICATION:** FIRE, MARINE & CASUALTY INSURANCE [6331]
- **ORGANIZATION NAME:** 02 Finance
- **EIN:** 221867895
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-15202
- **FILM NUMBER:** 251551379

**BUSINESS ADDRESS:**
- **STREET 1:** 475 STEAMBOAT ROAD
- **STREET 2:** .
- **CITY:** GREENWICH
- **STATE:** CT
- **ZIP:** 06830
- **BUSINESS PHONE:** 2036293000

**MAIL ADDRESS:**
- **STREET 1:** 475 STEAMBOAT ROAD
- **STREET 2:** .
- **CITY:** GREENWICH
- **STATE:** CT
- **ZIP:** 06830

?xml version='1.0' encoding='ASCII'? 8-K

### 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): December 5, 2025

#### Commission File Number 1-15202
W. R. BERKLEY CORPORATION

#### (Exact name of registrant as specified in its charter)

---

| | |
|:---|:---|
| **Delaware** | **22-1867895** |
| **(State or other jurisdiction**<br> **of incorporation or organization)** | **(I.R.S. Employer<br>Identification No.)** |

---

---

| | | | |
|:---|:---|:---|:---|
| **475 Steamboat Road** | **Greenwich** | **Connecticut** | **06830** |
| **(Address of principal executive offices)** |  |  | **(Zip Code)** |

---

(203) 629-3000

#### (Registrant's telephone number, including area code)

#### None

#### (Former name, former address and former fiscal year, 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 registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

---

| | | |
|:---|:---|:---|
| **Title of each class** | **Trading<br>Symbol(s)** | **Name of each exchange**<br> **on which registered** |
| Common Stock, par value $.20 per share | WRB | New York Stock Exchange |
| 5.700% Subordinated Debentures due 2058 | WRB-PE | New York Stock Exchange |
| 5.100% Subordinated Debentures due 2059 | WRB-PF | New York Stock Exchange |
| 4.250% Subordinated Debentures due 2060 | WRB-PG | New York Stock Exchange |
| 4.125% Subordinated Debentures due 2061 | WRB-PH | New York Stock Exchange |

---

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 8.01** | **Other Events**  |

---

On December 5, 2025, W. R. Berkley Corporation (the "Company") issued a press release announcing that the Company has been informed by representatives of Mitsui Sumitomo Insurance Co., Ltd. ("MSI") that MSI has acquired beneficial ownership of at least 12.5% of the Company's outstanding common stock (the "Common Stock") pursuant to MSI's previously announced agreements with a company owned by members of the Berkley family and trusts for their benefit. The press release is attached as Exhibit 99.1 and incorporated by reference.

---

| | |
|:---|:---|
| **Item 9.01.** | **Financial Statements and Exhibits.**  |

---

(d) Exhibits.

---

| | |
|:---|:---|
| **Exhibit No.** | **Description** |
| 99.1 | [Press Release, issued December 5, 2025.](d53561dex991.htm) |
| 104 | Cover Page Interactive Data File (embedded within the Inline XBRL document). |

---

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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.

---

| | |
|:---|:---|
| **W. R. BERKLEY CORPORATION** | **W. R. BERKLEY CORPORATION** |
| By: | /s/ Richard M. Baio |
|  | Name: Richard M. Baio |
|  | Title: Executive Vice President – Chief Financial Officer |

---

Date: December 5, 2025

## Exhibit 99.1

**Exhibit 99.1** 

**W. R. Berkley Corporation Has Been Informed That Mitsui Sumitomo Insurance Co. Has Acquired Beneficial Ownership of At Least 12.5% of the Company's Shares Pursuant to Previously Announced Agreements with the Berkley Family** 

**GREENWICH, Conn.,** December 5, 2025**—**W. R. Berkley Corporation (NYSE: WRB) (the "Company") today announced that the Company has been informed by representatives of Mitsui Sumitomo Insurance Co., Ltd. ("MSI"), a leading Japanese property and casualty insurance carrier, that MSI has acquired beneficial ownership of at least 12.5% of the Company's outstanding common stock (the "Common Stock") pursuant to MSI's previously announced agreements with a company owned by members of the Berkley family and trusts for their benefit (collectively, the "Berkley Family"). None of MSI's shares were purchased from the Berkley Family or the Company.

Under the agreements with the Berkley Family, MSI's shares will be voted pursuant to the recommendations of the Berkley Family, except in limited circumstances where the MSI shares will be voted in the same proportion as all of the non-MSI shares are voted.

The Company has been informed by representatives of MSI that they expect to complete their investment under the agreements with the Berkley Family in the first quarter of 2026.

The description of the agreements between MSI and the Berkley Family are qualified in their entirety by reference to the full text of the agreements attached as exhibits to the Form 8-K filed by the Company on March 28, 2025. A copy of the Form 8-K can be found on the Investor Relations section of our <u>website</u>. For further information about Mitsui Sumitomo Insurance Co., Ltd., please visit <u>https://www.ms-ins.com/english/</u>.

**About W. R. Berkley Corporation** 

Founded in 1967, W. R. Berkley Corporation is an insurance holding company that is among the largest commercial lines writers in the United States and operates worldwide in two segments of the property casualty insurance business: Insurance and Reinsurance & Monoline Excess. For further information about W. R. Berkley Corporation, please visit www.berkley.com.

**Forward-Looking Statements** 

This is a "Safe Harbor" Statement under the Private Securities Litigation Reform Act of 1995. Any forward-looking statements contained herein are based upon the Company's historical performance and on current plans, estimates and expectations. The inclusion of this forward-looking information should not be regarded as a representation by us or any other person that the future plans, estimates or expectations contemplated by us will be achieved. They are subject to various risks and uncertainties. These risks could cause actual results of the industry or our actual results for the year 2025 and beyond to differ materially from those expressed in any forward-looking statement made by or on behalf of the Company. Forward-looking statements speak only as of the date on which they are made, and the Company undertakes no obligation to update publicly or revise any forward-looking statement, whether as a result of new information, future developments or otherwise.

**###** 

------

Karen A. Horvath

Vice President - External

Financial Communications

(203) 629-3000

Source: W. R. Berkley Corporation