X0202 4 2006-05-24 0 0000109261 ZENITH NATIONAL INSURANCE CORP ZNT 0001238322 KAMPELMAN MAX M FRIED, FRANK, HARRIS, SHRIVER & JACOBSON 1001 PENNSYLVANIA AVE., NW SUITE 800 WASHINGTON DC 20004 1 0 0 0 Common Stock 2006-05-24 4 A 0 2250 0 A 11988 D Previously reported number of 6,492 shares increased to 9,738 due to a three-for-two stock split distributed on October 11, 2005, to stockholders of record on September 19, 2005. /s/ Max Kampelman 2006-05-24