White Mountains Insurance Group (WTM) EVP & counsel updates share holdings

Rhea-AI Filing Summary

White Mountains Insurance Group executive vice president and general counsel reported changes in his holdings of the company’s common shares. On January 1, 2026, 1,000 restricted common shares became unrestricted, and 398 of those shares were withheld by the company to cover tax obligations at a reported value of $2,078.03. Following this transaction, he beneficially owns 17,907 common shares directly, 1,725 restricted common shares directly, 4 common shares indirectly through his wife and dependent children, and 583 common shares indirectly through the White Mountains Retirement Plan, which includes an accumulation of 3 shares since his prior report as of a plan statement dated December 22, 2025.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

SEELIG ROBERT LAWRENCE

(Last) (First) (Middle)

C/O WHITE MOUNTAINS INSURANCE GROUP, LTD

23 SOUTH MAIN STREET, SUITE 3B

(Street)

HANOVER NH 03755

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
WHITE MOUNTAINS INSURANCE GROUP LTD [ WTM ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP & General Counsel

3. Date of Earliest Transaction (Month/Day/Year)
01/01/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Shares	01/01/2026		F		398	D	$2,078.03	17,907(1)	D
Common Shares (restricted)								1,725(1)	D
Common Shares								4	I	by wife and dependent children
Common Shares								583(2)	I	By WTM Retirement Plan

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. On January 1, 2026, 1,000 restricted Common Shares became unrestricted. 398 of the Common Shares were withheld by the Company to satisfy the Reporting Person's tax obligations.

2. Reflects accumulation of 3 Common Shares in Reporting Person's White Mountains Retirement account since his last filed report. The information in this report is based on a plan report dated as of December 22, 2025.

	Wesley C. Bell, by Power of Attorney	01/02/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction did White Mountains Insurance Group (WTM) report?

The executive vice president and general counsel reported that on January 1, 2026, 1,000 restricted common shares became unrestricted, with 398 shares withheld by the company to satisfy tax obligations.

How many White Mountains (WTM) shares were withheld for taxes?

The report states that 398 common shares were withheld by the company to cover the reporting person’s tax obligations when the restricted shares vested.

What are the reporting person’s direct holdings in White Mountains (WTM) after the transaction?

After the reported transaction, the executive beneficially owns 17,907 common shares directly and 1,725 restricted common shares directly.

Does the White Mountains (WTM) insider hold any indirect shares?

Yes. The insider reports indirect ownership of 4 common shares through his wife and dependent children and 583 common shares through the White Mountains Retirement Plan.

What does the footnote about the White Mountains Retirement Plan indicate?

The footnote explains that the 583 common shares in the White Mountains Retirement Plan reflect an accumulation of 3 additional shares since the last report, based on a plan report dated December 22, 2025.

Who is the reporting person in this White Mountains (WTM) Form 4 filing?

The reporting person is an officer of White Mountains Insurance Group Ltd, serving as executive vice president and general counsel.