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<SEC-DOCUMENT>0001104659-11-003927.txt : 20110131
<SEC-HEADER>0001104659-11-003927.hdr.sgml : 20110131
<ACCEPTANCE-DATETIME>20110131161240
ACCESSION NUMBER:		0001104659-11-003927
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20110131
DATE AS OF CHANGE:		20110131

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BYRNE JOHN J
		CENTRAL INDEX KEY:			0000901312

	FILING VALUES:
		FORM TYPE:		SC 13G/A

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			WHITE MOUNTAINS INSURANCE GROUP LTD
		CENTRAL INDEX KEY:			0000776867
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		IRS NUMBER:				942708455
		STATE OF INCORPORATION:			D0
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-36786
		FILM NUMBER:		11559636

	BUSINESS ADDRESS:	
		STREET 1:		80 SOUTH MAIN ST
		CITY:			HANOVER
		STATE:			NH
		ZIP:			03755
		BUSINESS PHONE:		603 640 2200

	MAIL ADDRESS:	
		STREET 1:		80 SOUTH MAIN STREET
		CITY:			HANOVER
		STATE:			NH
		ZIP:			03755

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	WHITE MOUNTAINS INSURANCE GROUP INC
		DATE OF NAME CHANGE:	19990603

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FUND AMERICAN ENTERPRISES HOLDINGS INC
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FUND AMERICAN COMPANIES INC
		DATE OF NAME CHANGE:	19920701
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>a11-4753_1sc13ga.htm
<DESCRIPTION>SC 13G/A
<TEXT>


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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">SECURITIES   AND EXCHANGE COMMISSION</font></b></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
<td width="53%" valign="top" style="padding:0in .7pt .7pt .7pt;width:53.16%;">
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Washington,   D.C. 20549</font></b></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
<td width="53%" valign="top" style="padding:0in .7pt .7pt .7pt;width:53.16%;">
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
<td width="23%" valign="top" style="padding:0in .7pt .7pt .7pt;width:23.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>  </table>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">SCHEDULE 13G</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">(Rule 13d-102)</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">&nbsp;</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">TO RULES 13d-1(b) (c), AND (d) AND AMENDMENTS THERETO FILED</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">PURSUANT TO RULE 13d-2</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">(Amendment No.&nbsp;&nbsp;13)*</font></b></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<div style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;">
<p align="center" style="border:none;margin:0in 0in .0001pt;padding:0in;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">WHITE MOUNTAINS INSURANCE GROUP, LTD.</font></b></p>
</div>
<p align="center" style="margin:0in 0in 12.0pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Name of Issuer)</font></p>
<div style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in;">
<p align="center" style="border:none;margin:0in 0in .0001pt;padding:0in;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Common Shares</font></b></p>
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<p align="center" style="margin:0in 0in 12.0pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Title of Class of Securities)</font></p>
<div style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in;">
<p align="center" style="border:none;margin:0in 0in .0001pt;padding:0in;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">G9618E 10 7</font></b></p>
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<p align="center" style="margin:0in 0in 12.0pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(CUSIP Number)</font></p>
<div style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in;">
<p align="center" style="border:none;margin:0in 0in .0001pt;padding:0in;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">December 31, 2010</font></b></p>
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<p align="center" style="margin:0in 0in 12.0pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Date of Event Which Requires Filing of this Statement)</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Check the appropriate box to designate the rule pursuant to which this Schedule is filed: </font></p>
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.46%;">
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font></p>    </td>
<td width="90%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.54%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Rule 13d-1(b)</font></p>    </td>   </tr>
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.46%;">
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font></p>    </td>
<td width="90%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.54%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Rule 13d-1(c)</font></p>    </td>   </tr>
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.46%;">
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Wingdings" style="font-size:10.0pt;">x</font></p>    </td>
<td width="90%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.54%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Rule 13d-1(d)</font></p>    </td>   </tr>  </table>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">*The remainder of this cover page shall be filled out for a reporting 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. </font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The information required in the remainder of this cover page shall not be deemed to the &quot;filed&quot; for the purpose of Section 18 of the Securities Exchange Act of 1934 (&quot;Act&quot;) 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).</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
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<div style="font-family:Times New Roman;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
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<td width="100%" colspan="6" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">CUSIP No.&nbsp;G9618E 10 7</font></p>    </td>   </tr>
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<td width="100%" colspan="6" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<td width="3%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.44%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">1</font></p>    </td>
<td width="91%" colspan="4" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:91.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Name of Reporting Persons</font><font size="2" style="font-size:10.0pt;"><br>   S.S. (Optional) or I.R.S. Identification No. of Above Persons</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">John J. Byrne</font></p>    </td>   </tr>
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<td width="100%" colspan="6" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<td width="3%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.44%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">2</font></p>    </td>
<td width="91%" colspan="4" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:91.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Check the Appropriate Box   if a Member of a Group</font></p>    </td>   </tr>
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<td width="3%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.44%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(a)</font></p>    </td>
<td width="86%" colspan="2" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:86.04%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font></p>    </td>   </tr>
<tr>
<td width="3%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.44%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(b)</font></p>    </td>
<td width="86%" colspan="2" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:86.04%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font></p>    </td>   </tr>
<tr>
<td width="100%" colspan="6" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="3%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.44%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">3</font></p>    </td>
<td width="91%" colspan="4" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:91.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">SEC Use Only </font></p>    </td>   </tr>
<tr>
<td width="100%" colspan="6" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="3%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.44%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4</font></p>    </td>
<td width="91%" colspan="4" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:91.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Citizenship or Place of   Organization </font><font size="2" style="font-size:10.0pt;"><br>   United States</font></p>    </td>   </tr>
<tr>
<td width="13%" colspan="3" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:13.84%;">
<p style="margin-left:0in;margin-right:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="4%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:4.94%;">
<p align="right" style="margin-left:0in;margin-right:0in;text-align:right;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="81%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:81.24%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr style="page-break-inside:avoid;">
<td width="13%" colspan="3" rowspan="7" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:13.84%;">
<p style="margin-left:0in;margin-right:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Number of<br>   Shares<br>   Beneficially<br>   Owned by<br>   Each<br>   Reporting<br>   Person With</font></p>    </td>
<td width="4%" colspan="2" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:4.94%;">
<p style="margin-left:0in;margin-right:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">5</font></p>    </td>
<td width="81%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:81.24%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Sole Voting Power </font><font size="2" style="font-size:10.0pt;"><br>   700,496**</font></p>    </td>   </tr>
<tr style="page-break-inside:avoid;">
<td width="86%" colspan="3" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:86.16%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr style="page-break-inside:avoid;">
<td width="4%" colspan="2" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:4.94%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">6</font></p>    </td>
<td width="81%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:81.24%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Shared Voting Power</font><font size="2" style="font-size:10.0pt;">  <br>   31,273**</font></p>    </td>   </tr>
<tr style="page-break-inside:avoid;">
<td width="86%" colspan="3" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:86.16%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr style="page-break-inside:avoid;">
<td width="4%" colspan="2" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:4.94%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">7</font></p>    </td>
<td width="81%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:81.24%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Sole Dispositive Power</font><font size="2" style="font-size:10.0pt;">  <br>   700,496**</font></p>    </td>   </tr>
<tr style="page-break-inside:avoid;">
<td width="86%" colspan="3" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:86.16%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr style="page-break-inside:avoid;">
<td width="4%" colspan="2" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:4.94%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">8</font></p>    </td>
<td width="81%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:81.24%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Shared Dispositive Power <br>   31,273**</font></p>    </td>   </tr>
<tr>
<td width="100%" colspan="6" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="3%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.44%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">9</font></p>    </td>
<td width="91%" colspan="4" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:91.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Aggregate Amount   Beneficially Owned by Each Reporting Person</font><font size="2" style="font-size:10.0pt;"><br>   731,769**</font></p>    </td>   </tr>
<tr>
<td width="100%" colspan="6" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="3%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.44%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10</font></p>    </td>
<td width="91%" colspan="4" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:91.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Check if the Aggregate   Amount in Row (9) Excludes Certain Shares </font><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font></p>    </td>   </tr>
<tr>
<td width="100%" colspan="6" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="3%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.44%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">11</font></p>    </td>
<td width="91%" colspan="4" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:91.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Percent of Class   Represented by Amount in Row (9)</font><font size="2" style="font-size:10.0pt;"><br>   8.9%**</font></p>    </td>   </tr>
<tr>
<td width="100%" colspan="6" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="3%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="5%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:5.44%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">12</font></p>    </td>
<td width="91%" colspan="4" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:91.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Type of Reporting Person </font><font size="2" style="font-size:10.0pt;"><br>   IN</font></p>    </td>   </tr>
<tr height="0">
<td width="24" style="border:none;"></td>
<td width="41" style="border:none;"></td>
<td width="38" style="border:none;"></td>
<td width="1" style="border:none;"></td>
<td width="36" style="border:none;"></td>
<td width="608" style="border:none;"></td>   </tr> </table>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<div style="margin:0in 0in .0001pt;"><hr size="1" width="25%" noshade color="black" align="left"></div>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">**&#160; For additional information, see Schedule A hereto.</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">2<a name="PB_2_043312_7056"></a></font></p>
<div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
</div>
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<div>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.02%;">
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<td width="9%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.04%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 1(a).</font></b></p>    </td>
<td width="3%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.7%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="87%" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:87.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Name of Issuer:<br>   White Mountains Insurance Group, Ltd.</font></p>    </td>   </tr>
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<td width="9%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.04%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 1(b).</font></b></p>    </td>
<td width="3%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.7%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="87%" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:87.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Address of Issuer&#146;s   Principal Executive Offices:<br>   80 South Main Street</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Hanover, New Hampshire   03755</font></p>    </td>   </tr>
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<td width="100%" colspan="3" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<td width="9%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.04%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 2(a).</font></b></p>    </td>
<td width="3%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.7%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="87%" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:87.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Name of Person Filing:<br>   John J. Byrne</font></p>    </td>   </tr>
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<td width="9%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.04%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 2(b).</font></b></p>    </td>
<td width="3%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.7%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="87%" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:87.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Address of Principal   Business Office:<br>   80 South Main Street</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Hanover, New Hampshire   03755</font></p>    </td>   </tr>
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<td width="9%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.04%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 2(c).</font></b></p>    </td>
<td width="3%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.7%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="87%" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:87.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Citizenship:<br>   United States</font></p>    </td>   </tr>
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<td width="9%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.04%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 2(d).</font></b></p>    </td>
<td width="3%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.7%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="87%" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:87.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Title of Class of   Securities:<br>   Common Shares</font></p>    </td>   </tr>
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<td width="9%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.04%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 2(e).</font></b></p>    </td>
<td width="3%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:3.7%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="87%" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:87.26%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">CUSIP Number:<br>   G9618E 10 7</font></p>    </td>   </tr>
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<td width="100%" colspan="3" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<td width="9%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.04%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 3.</font></b></p>    </td>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">If this statement is filed pursuant   to Rules 13d-1(b), or 13d-2(b), check whether the person filing is a:</font></b></p>    </td>   </tr>
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.04%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="90%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.96%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Not applicable.</font></p>    </td>   </tr>  </table>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">3<a name="PB_3_043312_5335"></a></font></p>
<div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
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<div style="font-family:Times New Roman;">
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 4.</font></b></p>    </td>
<td width="90%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.28%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Ownership.</font></b></p>    </td>   </tr>
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:3.0pt 0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="4%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:4.12%;">
<p align="center" style="margin:3.0pt 0in;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(a)</font></p>    </td>
<td width="86%" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:86.16%;">
<p style="margin:3.0pt 0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Amount beneficially   owned:&nbsp;&nbsp;&nbsp; </font></p>
<p style="margin:3.0pt 0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">See Schedule A hereto.</font></p>    </td>   </tr>
<tr>
<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:3.0pt 0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="4%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:4.12%;">
<p align="center" style="margin:3.0pt 0in;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(b)</font></p>    </td>
<td width="86%" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:86.16%;">
<p style="margin:3.0pt 0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Percent of class:</font></p>
<p style="margin:3.0pt 0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">See Schedule A hereto.</font></p>    </td>   </tr>
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:3.0pt 0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="4%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:4.12%;">
<p align="center" style="margin:3.0pt 0in;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(c)</font></p>    </td>
<td width="86%" style="border:none;border-bottom:solid windowtext 1.0pt;padding:3.0pt 3.0pt 3.0pt 3.0pt;width:86.16%;">
<p style="margin:3.0pt 0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Number of shares as to   which person filing this Schedule 13G has (i) sole power to vote or to direct   the vote; (ii) shared power to vote or to direct the vote; (iii) sole power   to dispose or to direct the disposition of; or (iv) shared power to dispose   or to direct the disposition of.</font></p>
<p style="margin:3.0pt 0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">See Schedule A hereto.</font></p>    </td>   </tr>
<tr>
<td width="100%" colspan="3" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 5.</font></b></p>    </td>
<td width="90%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.28%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Ownership of Five Percent or Less   of a Class.</font></b></p>    </td>   </tr>
<tr>
<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
<td width="90%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.28%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">If this statement is being filed to report the fact   that as of the date hereof the reporting person has ceased to be the   beneficial owner of more than 5 percent of the class of securities, check the   following&nbsp;&nbsp; </font><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="2" style="font-size:10.0pt;">.</font></p>    </td>   </tr>
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<td width="100%" colspan="3" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:100.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 6.</font></b></p>    </td>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Ownership of More than Five Percent   on Behalf of Another Person.</font></b></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
<td width="90%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.28%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Not applicable.</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<td width="9%" valign="top" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 7.</font></b></p>    </td>
<td width="90%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.28%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Identification and Classification   of the Subsidiary Which Acquired the Security Being Reported on By the Parent   Holding Company.</font></b></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
<td width="90%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.28%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Not applicable.</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 8.</font></b></p>    </td>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Identification and Classification   of Members of the Group.</font></b></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
<td width="90%" colspan="2" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.28%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Not applicable.</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 9.</font></b></p>    </td>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Notice of Dissolution of Group.</font></b></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Not applicable.</font></p>    </td>   </tr>  </table>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4<a name="PB_4_043312_5796"></a></font></p>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
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<td width="9%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:9.72%;">
<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 10.</font></b></p>    </td>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Certification.</font></b></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
<td width="90%" style="padding:3.0pt 3.0pt 3.0pt 3.0pt;width:90.28%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Not applicable.</font></p>    </td>   </tr>  </table>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><u><font size="2" face="Times New Roman" style="font-size:10.0pt;">SIGNATURE</font></u></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">After reasonable inquiry and to the best of my knowledge and belief,&nbsp;I certify that the information set forth in this Statement is true, complete and correct.</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Date:&nbsp; January 31, 2011</font></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.92%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">By:</font></p>    </td>
<td width="46%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:46.08%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   John J. Byrne</font></p>    </td>   </tr>  </table>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">5<a name="PB_5_043312_2897"></a></font></p>
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<p style="margin:0in 0in .0001pt 5.0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><u><font size="2" face="Times New Roman" style="font-size:10.0pt;">Schedule A</font></u></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">BENEFICIAL OWNERSHIP AND VOTING OF COMMON SHARES</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The 8.9% of the common shares of White Mountains Insurance Group,&nbsp;Ltd. (the &#147;Company&#148;) shown in the foregoing Schedule 13G as beneficially owned by Mr.&nbsp;John J. Byrne and/or Mrs.&nbsp;Dorothy M. Byrne was calculated using 8,194,925 common shares of the Company outstanding on December&nbsp;31, 2010 as shown in the official records of the Company.</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The 731,769 common shares of the Company shown in the foregoing Schedule 13G as beneficially owned by Mr.&nbsp;Byrne represent (a)&nbsp;700,496 shares held directly by Mr.&nbsp;Byrne as to which Mr.&nbsp;Byrne has dispositive and voting power; (b)&nbsp;1,221 shares held directly by Mrs.&nbsp;Byrne as to which Mrs.&nbsp;Byrne has dispositive and voting power; (c)&nbsp;16,081 shares held by a foundation as to which Mr.&nbsp;Byrne and/or Mrs.&nbsp;Byrne have dispositive and voting power; and (d)&nbsp;13,971&#160; shares held by Memorial Sloan-Kettering Cancer Center (&#147;MSK&#148;) pursuant to a letter agreement between MSK and Mr.&nbsp;and Mrs.&nbsp;Byrne dated December&nbsp;30, 1992, as to which Mrs.&nbsp;Byrne shares dispositive and voting power.</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">On January&nbsp;22, 2007, Mr.&nbsp;and Mrs.&nbsp;Byrne irrevocably granted full proxy to vote certain of the shares shown above as beneficially owned by them (totaling 701,717 shares as of December&nbsp;31, 2010) to Mr.&nbsp;Raymond Barrette, Chairman and Chief Executive Officer of the Company, until the earlier of (i)&nbsp;January&nbsp;1, 2012 or (ii)&nbsp;the death of John J. Byrne.</font></p>
<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<div style="margin:0in 0in .0001pt;"><hr size="1" width="25%" noshade color="black" align="left"></div>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">*&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Mr.&nbsp;Byrne disclaims beneficial ownership of the shares listed in (c)&nbsp;and (d)&nbsp;above.</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">6<a name="PB_6_043312_3020"></a></font></p>
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