X0202 4 2006-11-06 0 0001333513 DealerTrack Holdings, Inc. TRAK 0001342016 ONeil Mark F C/O DEALERTRACK HOLDINGS, INC. 1111 MARCUS AVENUE, SUITE M04 LAKE SUCCESS NY 11042 1 1 0 0 Chairman of Board, Pres. & CEO Common Stock 2006-11-06 4 S 0 2500 26.44 D 301644 D Common Stock 2006-11-06 4 S 0 2500 26.4893 D 299144 D Common Stock 2006-11-06 4 S 0 2500 26.8106 D 296644 D Common Stock 2006-11-06 4 S 0 2500 26.8841 D 294144 D Common Stock 2006-11-06 4 S 0 2500 27.39 D 291644 D Common Stock 51164 I By Spouse Common Stock 90686 I as Trustee for The Mark F. O'Neil Qualified Grantor Retained Annuity Trust The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 12, 2005. Includes 227,500 shares of restricted common stock. /s/ Eric D. Jacobs as attorney-in-fact for Mark F. O'Neil 2006-11-06