X0201 4 2003-11-18 0 0000109261 ZENITH NATIONAL INSURANCE CORP ZNT 0001238639 MILLER JACK D 21255 CALIFA ST. WOODLAND HILLS CA 91367 0 1 0 0 Executive Vice President Common Stock 2003-11-18 4 M 0 400 19.1563 A 400 D Common Stock 2003-11-18 4 S 0 400 32.48 D 0 D Common Stock 558 I See Footnote Employee Stock Option (Right to Buy) 19.1563 2003-11-18 4 M 0 400 0 D 2005-02-23 Common Stock 400 39600 D Represents the approximate number of shares allocated to the reporting person's account in The Zenith 401(k) Plan as of November 18, 2003, the latest date for which such information is available. The option vests in four equal installments on February 24, 2001, 2002, 2003 and 2004. /s/ Jack D. Miller 2003-11-20