X0303 4 2010-01-04 0000792013 HARLEYSVILLE GROUP INC HGIC 0001276066 CLARK THOMAS E 355 MAPLE AVENUE HARLEYSVILLE PA 19438 0 1 0 0 Sr VP Common Stock 2010-01-04 4 M 0 5812 26.36 A 30434 D Common Stock 2010-01-04 4 M 0 6500 27.20 A 36934 D Common Stock 2010-01-04 4 M 0 6700 23.209 A 43634 D Common Stock 2010-01-04 4 M 0 10700 21.25 A 54334 D Common Stock 2010-01-04 4 M 0 8910 29.39 A 63244 D Common Stock 2010-01-04 4 S 0 38622 32.0013 D 25005 D Employee Stock Option Right-to-Buy 26.36 2010-01-04 4 M 0 5812 0 D 2011-05-23 Common Stock 5812 0 D Employee Stock Option Right-to-Buy 27.20 2010-01-04 4 M 0 6500 0 D 2012-05-22 Common Stock 6500 0 D Employee Stock Option Right-to-Buy 23.209 2010-01-04 4 M 0 6700 0 D 2013-05-20 Common Stock 6700 0 D Employee Stock Option Right-to-Buy 21.25 2010-01-04 4 M 0 10700 0 D 2015-02-23 Common Stock 10700 0 D Employee Stock Option Right-to-Buy 29.39 2010-01-04 4 M 0 8910 0 D 2016-04-26 Common Stock 8910 0 D The sales reported on this Form 4 were effected pursuant to a 10b5-1 trading plan adopted by reporting person on November 18, 2009. Total includes 382.806 shares acquired on 7/14/09 through participation in the HGI employee stock purchase plan. The option vested in 2 equal annual installments beginning on 5/23/02. The option vested in 2 equal annual installments beginning on 5/22/03. The option vested in 2 equal annual installments beginning on 5/20/04. The option vested in 2 equal annual installments beginning on 2/23/06. The option vested in 3 equal annual installments beginning on 4/26/07. Thomas E. Clark 2010-01-06