Director John Chu discloses 200 WTM common shares in initial Form 3 filing

Rhea-AI Filing Summary

WHITE MOUNTAINS INSURANCE GROUP LTD director John Chu has filed an initial ownership report on Form 3. The filing shows that he beneficially owns 200 common shares directly after the reported event. The document does not reflect any recent purchase or sale activity, only his starting stake as an insider.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Chu John

Role null

Type	Security	Shares	Price	Value
holding	Common Shares	--	--	--

Holdings After Transaction: Common Shares — 200 shares (Direct, null)

Footnotes (1)

Key Figures

Common shares owned: 200 shares

1 metrics

Common shares owned 200 shares Direct beneficial ownership reported on Form 3

Key Terms

Form 3, beneficially owns, Common Shares

3 terms

Form 3 regulatory

"John Chu has filed an initial ownership report on Form 3"

Form 3 is the initial public filing that officers, directors and large shareholders must submit to report their ownership of a company’s securities when they become insiders. It acts like an opening inventory sheet that gives investors a starting point to see who holds significant stakes and to spot later trades or potential conflicts of interest, helping assess insider confidence and transparency.

beneficially owns financial

"The filing shows that he beneficially owns 200 common shares directly"

Beneficially owns means a person or entity enjoys the economic benefits and control of a security even if the legal title or registration is held in another name. Think of it like having the keys and profits from a car that is registered to a friend: you use it, benefit from it, and make decisions about it even though the official paperwork lists someone else. For investors, this matters because it reveals who truly controls shares, affects voting power, potential conflicts of interest, and regulatory disclosure obligations.

Common Shares financial

"The filing shows that he beneficially owns 200 common shares directly"

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.

Understanding Insider Trading Forms →

SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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:			3235-0104
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hours per response:			0.5

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. Date of Event Requiring Statement (Month/Day/Year)
05/21/2026

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

3a. Foreign Trading Symbol

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

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

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

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 Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Shares	200	D

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

	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 5 (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 3: SEC 1473 (03-26)

FAQ

What does John Chu’s Form 3 filing for WTM report?

The Form 3 shows that director John Chu beneficially owns 200 common shares of WHITE MOUNTAINS INSURANCE GROUP LTD. It is an initial ownership statement and does not indicate any recent purchase or sale transactions.

How many WHITE MOUNTAINS (WTM) shares does John Chu own?

The filing reports that John Chu beneficially owns 200 common shares of WHITE MOUNTAINS INSURANCE GROUP LTD. These shares are held directly in his name, establishing his initial disclosed stake as a company director.

Does John Chu’s WTM Form 3 indicate any recent insider trading?

No, the Form 3 does not show any recent insider trading. It only lists John Chu’s existing beneficial ownership of 200 common shares, serving as a baseline disclosure when he became a reporting insider.

Is John Chu a director or officer of WHITE MOUNTAINS (WTM)?

The filing identifies John Chu as a director of WHITE MOUNTAINS INSURANCE GROUP LTD and not as an officer. His Form 3 focuses on disclosing his direct ownership of 200 common shares in that role.

Does the WTM Form 3 filing show direct or indirect share ownership?

The filing classifies John Chu’s 200 common shares as directly owned. There is no indication of indirect holdings through trusts, partnerships, or other entities in the disclosed data for this Form 3.