X0201 4 2003-10-20 0 0000073124 NORTHERN TRUST CORP NTRS 0001188085 PERO PERRY R 50 S LA SALLE ST CHICAGO IL 60675 0 1 0 0 Vice Chairman & CFO Common Stock 2003-10-20 4 M 0 3532 28.3125 A 601261 D Common Stock 108557 D Common Stock 15390 I ESOP Common Stock 87888 I 401(k) Employee Stock Option (right to buy) 28.3125 2003-10-20 4 M 0 3532 0 D 1999-09-16 2007-09-16 Common Stock 3532 46468 D Common Stock Award 0 Common Stock 26000 26000 D Represents stock units payable automatically in shares of common stock on a 1-for-1 basis. as of 6/30/2003 with tandem tax withholding right Shares vest in installments determined by the satisfaction of a 3-year employment period. Eileen C. Ratzka as POA for Perry R. Pero 2003-10-21