X0303 4 2010-02-22 0 0001163348 ALLIED WORLD ASSURANCE CO HOLDINGS LTD AWH 0001456268 Gauthier John J ALLIED WORLD ASSURANCE CO HOLDINGS, LTD 27 RICHMOND ROAD PEMBROKE D0 HM 08 BERMUDA 0 1 0 0 SVP & C.I.O., Newmarket Admin Common Shares 2010-02-22 4 A 0 255 0.00 A 3998 D Restricted Stock Units 2010-02-22 4 A 0 4400 0.00 A Common Shares 2640 7400 D Represents the Company's Common Shares acquired pursuant to its 2008 Employee Share Purchase Plan on December 31, 2009. Grant of Restricted Stock Units for no monetary consideration. 4,400 Restricted Stock Units convert into (i) 2,640 of the Company's Common Shares and (ii) cash equal to the market value of 1,760 Common Shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units. The Restricted Stock Units vest in four equal installments with the first installment vesting on February 22, 2011. /s/ Wesley D. Dupont, by Power of Attorney 2010-02-24