X0306 4 2014-02-22 0 0001163348 Allied World Assurance Co Holdings, AG AWH 0001368326 Grossack Marshall J ALLIED WORLD ASSURANCE CO. HOLDINGS, AG LINDENSTRASSE 8 BAAR/ZUG V8 CH-6340 SWITZERLAND 0 1 0 0 EVP, Chief Actuary Common Shares 2014-02-22 4 M 0 488 0.00 A 67590 D Common Shares 2014-02-22 4 M 0 298 0.00 A 67888 D Common Shares 2014-02-22 4 M 0 825 0.00 A 68713 D Common Shares 2014-02-22 4 D 0 869 99.8969 D 67844 D Common Shares 2014-02-22 4 F 0 379 99.55 D 67465 D Restricted Stock Units 2014-02-22 4 M 0 488 D Common Shares 488 5786 D Restricted Stock Units 2014-02-22 4 M 0 298 D Common Shares 298 5488 D Restricted Stock Units 2014-02-22 4 M 0 825 D Common Shares 825 4663 D On February 22, 2012, the reporting person was granted 1,950 Restricted Stock Units for no monetary consideration. The Restricted Stock Units convert into (i) 390 common shares and (ii) cash equal to the market value of 1,560 common shares (measured at the date of vesting) of such Restricted Stock Units. On February 22, 2011, the reporting person was granted 1,190 Restricted Stock Units for no monetary consideration. The Restricted Stock Units convert into (i) 595 common shares and (ii) cash equal to the market value of 595 common shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units. On February 22, 2010, the reporting person was granted 3,300 Restricted Stock Units for no monetary consideration. The Restricted Stock Units convert into (i) 1,980 common shares and (ii) cash equal to the market value of 1,320 common shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units. The fair market value of the cash portion was determined using the daily volume-weighted average sales price of the common shares for the five consecutive trading days prior to February 22, 2014, which was on a Saturday. Exclusively represents shares withheld by the Company with respect to the payment of withholding tax liability incurred upon the vesting of Restricted Stock Units. The Restricted Stock Units vest in four equal installments with the first installment vesting on February 22, 2013. Represents all Restricted Stock Units held by the reporting person that vest in whole or in part in cash. The Restricted Stock Units vest in four equal installments with the first installment vesting on February 22, 2012. The Restricted Stock Units vested in four equal installments with the first installment vesting on February 22, 2011. /s/ Wayne H. Datz, by Power of Attorney 2014-02-25