UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 13F Form 13F COVER PAGE Report for the Calendar Year or Quarter Ended: December 31, 2003 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: Alleghany Corporation Address: 375 Park Avenue New York, NY 10152 Form 13F File Number: 28-1590 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: Peter R. Sismondo Title: Vice President, Controller, Treasurer and Assistant Secretary Phone: 212-752-1356 Signature, Place, and Date of Signing: /s/ Peter R. Sismondo New York, NY February 11, 2004 -------------------------------------------------------------------------------- [Signature] [City, State] [Date] Report Type (Check only one): [X] 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).) [ ] 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).) Form 13F SUMMARY PAGE Report Summary: Number of Other Included Managers: 1 Form 13F Information Table Entry Total: 81 Form 13F Information Table Value Total: $620,961 (thousands) List of Other Included Managers: No. Form 13F File Number Name --- -------------------- ---- 2 RSUI Indemnity Company SECURITIES AND EXCHANGE COMMISSIONS FORM 13F INFORMATION PREPARED FOR ALLEGHANY CORPORATION AS OF 12/31/03 COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8 ---------------------------- -------------- ---------- -------- -------------------- ----------------- ------- --------------- INVESTMENT VOTING NAME OF ISSUER TITLE OF CLASS CUSIP MARKET SHRS OR SH/ PUT/ DISCRETION MANAGER AUTHORITY VALUE PRIN AMT PRN CALL SOLE SHRD OTHER SOLE SHRD NONE (X 1000) (A) (B) (C) (A) (B) (C) ---------------------------- -------------- ---------- -------- ---------- --- ---- ---- ---- ----- ------- ---- ---- ---- ALTRIA GROUP INC COM 02209S103 1,361 25,000 SH X 1 X AMB PROPERTY CORP COM 00163T109 2,436 74,100 SH X 1 X ALEXANDER & BALDWIN INC COM 014482103 506 15,000 SH X 1 X AMEREN CORP COM 023608102 4,600 100,000 SH X 1 X AMERICAN EXPRESS CO COM 025816109 965 20,000 SH X 1 X AMERICAN INTL GROUP INC COM 026874107 1,326 20,000 SH X 1 X APPLERA CORP COM AP BIO GRP 038020103 828 40,000 SH X 1 X APPLIED MATLS INC COM 038222105 561 25,000 SH X 1 X ARCH COAL INC COM 039380100 8,479 272,035 SH X 1 X ARCH COAL INC COM 039380100 19,574 627,965 SH X 2 X ARCHSTONE SMITH TR COM 039583109 2,479 88,593 SH X 1 X AUTODESK INC COM 052769106 615 25,000 SH X 1 X AVALONBAY CMNTYS INC COM 053484101 2,312 48,364 SH X 1 X AVERY DENNISON CORP COM 053611109 560 10,000 SH X 1 X BANK OF AMERICA CORPORATION COM 060505104 8,043 100,000 SH X 1 X BERKSHIRE HATHAWAY INC DEL CL B 084670207 11,227 1,531 SH X 1 X BIOGEN IDEC INC COM 09062X903 918 25,000 SH X 1 X BOEING CO COM 097023105 632 15,000 SH X 1 X BURLINGTON RES INC COM 122014103 554 10,000 SH X 1 X BURLINGTON NORTHN SANTA FE C COM 12189T104 258,800 8,000,000 SH X 1 X CIGNA CORP COM 125509109 85,497 1,486,910 SH X 1 X CIGNA CORP COM 125509109 121,940 2,120,690 SH X 2 X CATERPILLAR INC DEL COM 149123101 830 10,000 SH X 1 X CHUBB CORP COM 171232101 1,022 15,000 SH X 1 X CINERGY CORP COM 172474108 3,881 100,000 SH X 1 X COCA COLA CO COM 191216100 1,269 25,000 SH X 1 X CONOCOPHILLIPS COM 20825C104 984 15,000 SH X 1 X CORPORATE OFFICE PPTYS TR SH BEN INT 22002T108 2,428 115,600 SH X 1 X COSTCO WHSL CORP NEW COM 22160K105 1,115 30,000 SH X 1 X COX COMMUNICATIONIS INC NEW CL A 224044107 1,034 30,000 SH X 1 X DEERE & CO COM 244199105 976 15,000 SH X 1 X DISNEY WALT CO COM DISNEY 254687106 1,050 45,000 SH X 1 X DOW CHEM CO COM 260543103 1,039 25,000 SH X 1 X EQUITY RESIDENTIAL SH BEN INT 29476L107 2,272 77,000 SH X 1 X EXXON MOBIL CORP COM 30231G102 1,230 30,000 SH X 1 X FEDERAL REALTY INVT TR SH BEN INT NEW 313747206 2,282 59,440 SH X 1 X FEDEX CORP COM 31428X106 1,013 15,000 SH X 1 X GRAINGER W W INC COM 384802104 948 20,000 SH X 1 X GREAT PLAINS ENERGY INC COM 391164100 3,182 100,000 SH X 1 X GUIDANT CORP COM 401698105 1,204 20,000 SH X 1 X HEARST-ARGYLE TELEVISION INC COM 422317107 551 20,000 SH X 1 X INTEL CORP COM 458140100 641 20,000 SH X 1 X INTERNATIONAL BUSINESS MACHS COM 459200101 1,112 12,000 SH X 1 X JEFFERSON PILOT CORP COM 475070108 1,013 20,000 SH X 1 X JOHNSON & JOHNSON COM 478160104 2,583 50,000 SH X 1 X LAUDER ESTEE COS INC CL A 518439104 589 15,000 SH X 1 X LIBERTY MEDIA CORP NEW COM SER A 530718105 1,308 110,000 SH X 1 X LILLY ELI & CO COM 532457108 1,055 15,000 SH X 1 X LINDSAY MFG CO COM 535555106 379 15,000 SH X 1 X MBIA INC COM 55262C100 296 5,000 SH X 1 X MACERICH CO COM 554382101 2,466 55,410 SH X 1 X MACK CALI RLTY CORP COM 554489104 2,372 57,000 SH X 1 X MANPOWER INC COM 56418H100 706 15,000 SH X 1 X MARSH & MCLENNAN COS INC COM 571748102 1,437 30,000 SH X 1 X MEDTRONIC INC COM 585055106 1,458 30,000 SH X 1 X MERCK & CO INC COM 589331107 693 15,000 SH X 1 X MICROSOFT CORP COM 594918104 1,916 70,000 SH X 1 X MILLIPORE CORP COM 601073109 1,292 30,000 SH X 1 X NEWELL RUBBERMAID INC COM 651229106 455 20,000 SH X 1 X NOBLE ENERGY INC COM 655044105 666 15,000 SH X 1 X NEWS CORP LTD SP ADR PFD 652487802 1,059 35,000 SH X 1 X NORDSTROM INC COM 655664100 686 20,000 SH X 1 X NOVARTIS AG SPONSORED ADR 66987V109 1,147 25,000 SH X 1 X OLD REP INTL CORP COM 680223104 3,804 150,000 SH X 1 X PEPCO HOLDINGS INC COM 713291902 1,954 100,000 SH X 1 X PINNACLE WEST CAP CORP COM 723484101 4,002 100,000 SH X 1 X PUBLIC STORAGE INC COM 74460D109 2,226 51,300 SH X 1 X ROHM & HAAS CO COM 775371107 1,068 25,000 SH X 1 X RYDER SYS INC COM 783549108 683 20,000 SH X 1 X SBC COMMUNICATIONS INC COM 78387G103 1,304 50,000 SH X 1 X SL GREEN RLTY CORP COM 78440X101 2,393 58,300 SH X 1 X SAFECO CORP COM 786429100 3,893 100,000 SH X 1 X SCHLUMBERGER LTD COM 806857108 1,094 20,000 SH X 1 X SIGMA ALDRICH CORP COM 826552101 572 10,000 SH X 1 X SONY CORP ADR NEW 835699307 693 20,000 SH X 1 X TAUBMAN CTRS INC COM 876664103 2,122 103,000 SH X 1 X TEXAS INSTRS INC COM 882508104 588 20,000 SH X 1 X 1 COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8 ---------------------------- -------------- ---------- -------- -------------------- ----------------- ------- --------------- INVESTMENT VOTING NAME OF ISSUER TITLE OF CLASS CUSIP MARKET SHRS OR SH/ PUT/ DISCRETION MANAGER AUTHORITY VALUE PRIN AMT PRN CALL SOLE SHRD OTHER SOLE SHRD NONE (X 1000) (A) (B) (C) (A) (B) (C) ---------------------------- -------------- ---------- -------- ---------- --- ---- ---- ---- ----- ------- ---- ---- ---- 3M CO COM 88579Y101 1,275 15,000 SH X 1 X UNITED DOMINION REALTY TR IN COM 910197102 2,383 124,100 SH X 1 X UNITED FIRE & CAS CO COM 910331107 3,055 75,684 SH X 1 X WACHOVIA CORP 2ND NEW COM 929903102 932 20,000 SH X 1 X WAL MART STORES INC COM 931142103 1,592 30,000 SH X 1 X WEYERHAUSER CO COM 962166104 1,280 20,000 SH X 1 X GRAND TOTAL 620,961 15,639,022 2