X0202 4 2007-08-28 0 0001158324 COGENT COMMUNICATIONS GROUP INC CCOI 0001296418 Harrison R Reed 1015 31ST ST. NW WASHINGTON DC 20007 0 1 0 0 President & COO common stock 2007-08-28 4 M 0 15000 6 A 45000 D Option to purchase common stock 6 2007-08-28 4 M 0 15000 0 A 2004-07-14 2014-07-14 common stock 15000 143119 D On August 28, 2007 Mr. Harrison exercised options to acquire 15,000 shares of common stock at a price of $6.00 per share. A portion of these securities is not vested. R. Reed Harrison, III 2007-08-29