White Mountains Insurance (WTM) SC 13G/A White Mountains Insurance Group LTD

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 1)*

White Mountains Insurance Group, Ltd.

(Name of Issuer)

Common Shares, $1.00 par value per share

(Title of Class of Securities)

G9618E 10 7

(CUSIP Number)

December 31, 2013

(Date of Event which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

¨           Rule 13d-1(b)

þ           Rule 13d-1(c)

¨           Rule 13d-1(d)

* The remainder of this cover page shall be filled out for a person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. G9618E 10 7 13G

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS Jack Byrne 2011 GRAT No. 1
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a) o (b) ¨
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION New Hampshire
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:		5	SOLE VOTING POWER 0
		6	SHARED VOTING POWER 0
		7	SOLE DISPOSITIVE POWER 0
		8	SHARED DISPOSITIVE POWER 0
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (See Instructions) Not Applicable
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0
12	TYPE OF REPORTING PERSON (See Instructions) OO

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CUSIP No. G9618E 10 7 13G

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS Jack Byrne 2011 GRAT No. 2
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a) o (b) ¨
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION New Hampshire
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:		5	SOLE VOTING POWER 0
		6	SHARED VOTING POWER 0
		7	SOLE DISPOSITIVE POWER 0
		8	SHARED DISPOSITIVE POWER 0
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (See Instructions) Not Applicable
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0
12	TYPE OF REPORTING PERSON (See Instructions) OO

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CUSIP No. G9618E 10 7 13G

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS Robert Snyder
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a) o (b) ¨
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION United States
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:		5	SOLE VOTING POWER 850
		6	SHARED VOTING POWER 0
		7	SOLE DISPOSITIVE POWER 850
		8	SHARED DISPOSITIVE POWER 0
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 850
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (See Instructions) Not Applicable
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0.01%
12	TYPE OF REPORTING PERSON (See Instructions) IN

4

CUSIP No. G9618E 10 7 13G

1	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS Daniel Mosley
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a) o (b) ¨
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION United States
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:		5	SOLE VOTING POWER 0
		6	SHARED VOTING POWER 0
		7	SOLE DISPOSITIVE POWER 0
		8	SHARED DISPOSITIVE POWER 0
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (See Instructions) Not Applicable
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0
12	TYPE OF REPORTING PERSON (See Instructions) IN

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Item 1.
	(a)	Name of Issuer:
		White Mountains Insurance Group, Ltd.
	(b)	Address of Issuer’s Principal Executive Offices:
		80 South Main Street
		Hanover, New Hampshire 03755
Item 2.
	(a)	Name of Persons Filing:
		Jack Byrne 2011 GRAT No. 1
		Jack Byrne 2011 GRAT No. 2
		Robert Snyder
		Daniel Mosley
	(b)	Address of Principal Business Office or, if none, Residence for each of the reporting persons:
		Jack Byrne 2011 GRAT No. 1
		16 King Road
		P.O. Box 85
		Etna, NH 03750
		Jack Byrne 2011 GRAT No. 2
		16 King Road
		P.O. Box 85
		Etna, NH 03750
		Robert Snyder
		16 King Road
		P.O. Box 85
		Etna, NH 03750
		Daniel Mosley
		Cravath, Swaine & Moore LLP
		825 Eighth Avenue
		New York, NY 10019
	(c)	Citizenship:
		Jack Byrne 2011 GRAT No. 1 – New Hampshire
		Jack Byrne 2011 GRAT No. 2 – New Hampshire
		Robert Snyder – United States
		Daniel Mosley – United States
	(d)	Title of Class of Securities:
		Common Shares
	(e)	CUSIP Number:
		G9618E 10 7

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G9618E 10 7
Item 3.	If this statement is filed pursuant to Rules 13d-1(b), or 13d-2(b), check whether the person filing is a:
	Not Applicable
Item 4.	Ownership:
	(a).	Amount beneficially owned:
		See the response to Item 9 on the attached cover pages.
	(b).	Percent of Class:
		See the response to Item 11 on the attached cover pages.
	(c).	Number of shares as to which such person has:
		(i).	Sole power to vote or to direct the vote:
		See the response to Item 5 on the attached cover pages.
		(ii).	Shared power to vote or to direct the vote:
		See the response to Item 6 on the attached cover pages.
		(iii).	Sole power to dispose or to direct the disposition of:
		See the response to Item 7 on the attached cover pages.
		(iv).	Shared power to dispose or to direct the disposition of:
		See the response to Item 8 on the attached cover pages.
Item 5.	Ownership of Five Percent or Less of a Class:
	If this statement is being filed to report the fact that as of the date hereof the reporting persons have ceased to be the beneficial owners of more than five percent of the class of securities, check the following: þ
Item 6.	Ownership of More than Five Percent on Behalf of Another Person:
	Not Applicable.
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person:
	Not Applicable
Item 8.	Identification and Classification of Members of the Group:
	Not Applicable.

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Item 9.	Notice of Dissolution of Group:
	See Exhibit 1 hereto.
Item 10.	Certification:
	By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.

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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: January 28, 2014

Jack Byrne 2011 GRAT No. 1
By:	/s/ Robert Snyder
	Name:	Robert Snyder
	Title:	Co-trustee

By:	/s/ Daniel Mosley
	Name:	Daniel Mosley
	Title:	Co-trustee

Jack Byrne 2011 GRAT No. 2
By:	/s/ Robert Snyder
	Name:	Robert Snyder
	Title:	Co-trustee

By:	/s/ Daniel Mosley
	Name:	Daniel Mosley
	Title:	Co-trustee
/s/ Robert Snyder
Robert Snyder
/s/ Daniel Mosley
Daniel Mosley

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Exhibit 1

Item 9 Information

Notice of Dissolution of a Group

On August 5, 2013, Jack Byrne 2011 GRAT No. 1, Jack Byrne 2011 GRAT No. 2 and Daniel Mosley ceased to own any shares of the common stock (together with Robert Snyder, the “Group”).  Accordingly, the Group dissolved on August 5, 2013.  All further filings with respect to transactions in the common stock will be filed, if required, by members of the Group, in their individual capacity.

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