X0202 4 2004-11-15 0001101215 ALLIANCE DATA SYSTEMS CORP ADS 0001212997 MACKESY D SCOTT C/O WELSH, CARSON, ANDERSON AND STOWE 320 PARK AVENUE, SUITE 2500 NEW YORK NY 10022 0 0 1 0 Common Stock 2004-11-15 4 S 0 687 43.22 D 3259 D The Reporting Person also indirectly beneficially owns 16,160,349 shares held by Welsh, Carson, Anderson & Stowe VIII, L.P. Pursuant to Instruction (4)(b)(iv) of Form 4, the Reporting Person has elected to report as indirectly beneficially owned the entire number of securities beneficially owned by such limited partnership. The Reporting Person is a managing member of the sole general partner of such limited partnership. The Reporting Person disclaims beneficial ownership of any securities, and any proceeds thereof, that exceed his pecuniary interest therein and/or that are not actually distributed to him. Jonathan M. Rather, Attorney-in-Fact 2004-11-16