Director John Chu receives 135-share award in WHITE MOUNTAINS (WTM)

Rhea-AI Filing Summary

Chu John reported acquisition or exercise transactions in this Form 4 filing.

WHITE MOUNTAINS INSURANCE GROUP LTD director John Chu received an award of 135 Common Shares as part of an Annual Director Share Award on May 21, 2026. The shares were granted at no cost and are a compensation-related issuance rather than an open-market purchase or sale.

Following this grant, Chu directly holds 335 Common Shares of the company.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Chu John

Role null

Type	Security	Shares	Price	Value
Grant/Award	Common Shares	135	$0.00	--

Holdings After Transaction: Common Shares — 335 shares (Direct, null)

Footnotes (1)

1. [object Object]

Key Figures

Shares granted: 135 Common Shares Price per share: $0.00 per share Shares held after grant: 335 Common Shares

3 metrics

Shares granted 135 Common Shares Annual Director Share Award on May 21, 2026

Price per share $0.00 per share Grant price for director share award

Shares held after grant 335 Common Shares Director John Chu direct holdings after transaction

Key Terms

Annual Director Share Award, Common Shares, Grant, award, or other acquisition

3 terms

Annual Director Share Award financial

"Annual Director Share Award"

Common Shares financial

"security_title: Common Shares"

Common shares are the basic units of ownership in a company that give holders a claim on profits and a right to vote on key matters, like electing the board. Think of them as membership cards in a club: they let you share in successes and losses, but in a bankruptcy or liquidation they are paid after creditors and preferred shareholders, so their value can swing more and matters for assessing risk and potential return.

Grant, award, or other acquisition financial

"transaction_code_description: Grant, award, or other acquisition"

Form 4 Insider Transactions: What Each Field Means →

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^*

Chu John

(Last) (First) (Middle)

C/O WHITE MOUNTAINS INSURANCE GROUP, LTD

23 SOUTH MAIN STREET, SUITE 3B

(Street)

HANOVER NEW HAMPSHIRE 03755

(City) (State) (Zip)

UNITED STATES

(Country)

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)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/21/2026

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

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

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

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	05/21/2026		A		135(1)	A	$0	335	D

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. Annual Director Share Award

	Wesley C. Bell, by Power of Attorney	05/21/2026
	** 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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did WHITE MOUNTAINS (WTM) director John Chu report?

John Chu reported receiving an award of 135 Common Shares of WHITE MOUNTAINS INSURANCE GROUP LTD. This was an Annual Director Share Award granted at no cost, reflecting stock-based compensation rather than an open-market trade.

Was John Chu’s May 21, 2026 WTM share transaction a purchase or a grant?

The transaction was a grant, not a market purchase. Chu acquired 135 Common Shares through an Annual Director Share Award, classified as a grant, award, or other acquisition under transaction code A on Form 4.

How many WHITE MOUNTAINS (WTM) shares does John Chu hold after this Form 4?

After the 135-share award, John Chu directly holds 335 Common Shares of WHITE MOUNTAINS INSURANCE GROUP LTD. This total reflects his position immediately following the reported compensation-related grant on May 21, 2026.

What does transaction code “A” mean in John Chu’s WTM Form 4 filing?

Transaction code “A” on the Form 4 indicates a grant, award, or other acquisition of securities. For John Chu’s filing, it reflects an Annual Director Share Award of 135 Common Shares rather than an open-market buy or sell.

Is John Chu’s Annual Director Share Award in WTM shares an open-market signal?

The award is a compensation-related grant, not an open-market trade. John Chu received 135 Common Shares at no cost as an Annual Director Share Award, which is a routine element of director compensation programs.