X0303 4 2011-01-03 0 0001163348 Allied World Assurance Co Holdings, AG AWH 0001063754 DILLARD JOAN H ALLIED WORLD ASSURANCE CO. HOLDINGS, AG LINDENSTRASSE 8 BAAR/ZUG V8 CH-6340 SWITZERLAND 0 1 0 0 EVP & CFO Common Shares 2011-01-03 4 S 0 5000 60.1087 D 84753 D The sale of Common Shares reported in this Form 4 were for tax purposes and were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 28, 2010. Represents a weighted average sale price: the sales prices range from $59.62 to $60.38. Upon request, the full sale information regarding the number of shares sold at each price increment will be provided to the Commission, the issuer or a security holder of the issuer. /s/ Wesley D. Dupont, Power of Attorney 2011-01-04