13F-HR 1 a2165169z13f-hr.txt 13F-HR UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 13F FORM 13F COVER PAGE Report for the Calendar Year or Quarter Ended: September 30, 2005 Check Here if Amendment / /; Amendment Number: --------- This Amendment (Check only one.): / / is a restatement. / / adds new holdings entries. Institutional Investment Manager Filing this Report: Name: White Mountains Advisors LLC Address: 370 Church Street Guilford, CT 06437 Form 13F File Number: 028-00470 The institutional investment manager filing this report and the person by whom it is signed hereby represent that the person signing the report is authorized to submit it, that all information contained herein is true, correct and complete, and that it is understood that all required items, statements, schedules, lists, and tables, are considered integral parts of this form. Person Signing this Report on Behalf of Reporting Manager: Name: Mark J. Plourde Title: Chief Financial Officer, Chief Compliance Officer & Treasurer Phone: (203) 458-5805 Signature, Place, and Date of Signing: /s/ Mark J. Plourde Guilford, Connecticut November 14, 2005 ------------------------------- --------------------- ----------------- [Signature] [City, State] [Date] Report Type (Check only one.): / / 13F HOLDINGS REPORT. (Check here if all holdings of this reporting manager are reported in this report.) / / 13F NOTICE. (Check here if no holdings reported are in this report, and all holdings are reported by other reporting manager(s).) /X/ 13F COMBINATION REPORT. (Check here if a portion of the holdings for this reporting manager are reported in this report and a portion are reported by other reporting manager(s).) List of Other Managers Reporting for this Manager: [If there are no entries in this list, omit this section.] Form 13F File Number Name 028-04685 Prospector Partners, LLC 028-05231 Pillar Point Equity Management, LLC 028-03130 Fenimore Asset Management, Inc. FORM 13F SUMMARY PAGE Report Summary: Number of Other Included Managers: 1 -------------------- Form 13F Information Table Entry Total: 1 -------------------- Form 13F Information Table Value Total: $156,783 -------------------- (thousands) List of Other Included Managers: Provide a numbered list of the name(s) and Form 13F file number(s) of all institutional investment managers with respect to which this report is filed, other than the manager filing this report. No. Form 13F File Number Name 01 028-01681 White Mountains Insurance Group, Ltd. WHITE MOUNTAINS ADVISORS LLC ---------------------------- WHITE MOUNTAINS ADVISORS LLC FORM 13F INFORMATION TABLE--SEPTEMBER 30, 2005
COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8 ------------------------- ---------------- --------- -------- ---------------------- ------------ ---------- ---------------------- VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGERS SOLE SHARED NONE ------------------------- ---------------- --------- -------- --------- ----- ------ ------------ ---------- ------ -------- ----- MONTPELIER RE HOLDINGS LTD SHS G62185106 $156,783 6,309,189 SH DEFINED 01 6,309,189
01 White Mountains Insurance Group, Ltd.