X0204 3 2012-03-01 0 0001163348 Allied World Assurance Co Holdings, AG AWH 0001543666 McElroy John Justin ALLIED WORLD ASSURANCE CO. HOLDINGS, AG LINDENSTRASSE 8 BAAR/ZUG V8 CH-6340 SWITZERLAND 0 1 0 0 COO Common Shares 41914 D Restricted Stock Units Common Shares 1000 D Restricted Stock Units Common Shares 2000 D Restricted Stock Units Common Shares 878 D Restricted Stock Units Common Shares 2242 D Employee Stock Options (right to buy) 31.47 2014-06-01 Common Shares 10000 D Employee Stock Options (right to buy) 35.01 2015-06-08 Common Shares 3333 D Employee Stock Options (right to buy) 61.51 2021-02-22 Common Shares 4430 D On February 26, 2009, the reporting person was granted 4,000 Restricted Stock Units for no monetary consideration. The Restricted Stock Units convert into (i) 2,000 of the Company's common shares and (ii) cash equal to the market value of 2,000 Common Shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units. The Restricted Stock Units vest in four equal annual installments with the first installment vesting on February 26, 2010. On February 22, 2010, the reporting person was granted 4,000 Restricted Stock Units for no monetary consideration. The Restricted Stock Units convert into cash equal to the market value of 4,000 Common Shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units. The Restricted Stock Units vest in four equal annual installments with the first installment vesting on February 22, 2011. On February 22, 2011, the reporting person was granted 1,170 Restricted Stock Units for no monetary consideration. The Restricted Stock Units convert into (i) 585 of the Company's common shares and (ii) cash equal to the market value of 585 Common Shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units. The Restricted Stock Units vest in four equal annual installments with the first installment vesting on February 22, 2012. On February 22, 2012, the reporting person was granted 2,242 Restricted Stock Units for no monetary consideration. The Restricted Stock Units convert into (i) 448 of the Company's common shares and (ii) cash equal to the market value of 1,794 Common Shares (measured at the date of vesting) upon the vesting of such Restricted Stock Units. The Restricted Stock Units vest in four equal annual installments with the first installment vesting on February 22, 2013. These Employee Stock Options vested in four equal annual installments with the first installment vesting on June 1, 2005. These Employee Stock Options vested in four equal annual installments with the first installment vesting on June 8, 2006. These Employee Stock Options vest in four equal annual installments with the first installment vesting on February 22, 2012. /s/ John J. McElroy 2012-03-12