X0203 3 2009-09-29 0 0001163348 ALLIED WORLD ASSURANCE CO HOLDINGS LTD AWH 0001362376 Sennott John Langton JR ALLIED WORLD ASSURANCE CO. HOLDINGS LTD 27 RICHMOND ROAD PEMBROKE D0 HM 08 BERMUDA 0 1 0 0 EVP, Chief Corp. Strat Officer Common Shares 12452 D Restricted Stock Units Common Shares 1500 D Includes 10,000 Restricted Stock Units which convert into Common Shares upon the vesting of such units on a one-for-one basis and 452 Common Shares of the Company acquired on June 30, 2009 pursuant to the Company's Employee Share Purchase Plan. The Restricted Stock Units vest in four equal annual installments with the first installment vesting on February 26, 2010. Grant of Restricted Stock Units for no monetary consideration. 3,000 Restricted Stock Units convert into (i) 1,500 Common Shares of the Company and (ii) cash equal to the market value of 1,500 Common Shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units. /s/ John L. Sennott, Jr. 2009-10-09