X0202 4 2007-08-23 0 0000109261 ZENITH NATIONAL INSURANCE CORP ZNT 0001238635 ZAVIS MICHAEL WM 17317 BRIDLEWAY TRAIL BOCA RATON FL 33496 1 0 0 0 Common Stock 2007-08-23 4 P 0 2500 43.00 A 4000 I See Footnote Common Stock 6707 I See Footnote Common Stock 6750 D Held in an irrevocable trust in which the reporting person is the sole beneficiary. Held in an irrevocable trust in which the wife of the reporting person is the sole beneficiary. The reporting person disclaims beneficial ownership of these securities, and this report shall not be deemed an admission that the reporting person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. /s/ Hyman J. Lee Jr., attorney in fact 2007-08-23