EXHIBIT 99 ---------- CONTACT: Sue Rageas Bev Fleming Public Relations Investor Relations (312) 444-4279 (312) 444-7811 FOR IMMEDIATE RELEASE --------------------- NORTHERN TRUST DECLARES QUARTERLY DIVIDEND; SHARE REPURCHASE AUTHORITY INCREASED CHICAGO, Wed., April 16, 2003 -- Northern Trust Corporation (Nasdaq:NTRS), holding company of The Northern Trust Company, yesterday declared a quarterly cash dividend of $0.17 per share on its common stock, $1.66-2/3 par value. The dividend is payable on July 1, 2003, to stockholders of record at the close of business on June 10, 2003. The Corporation also announced that its Board of Directors increased the Corporation's common stock buy-back authorization by approximately 11.5 million shares, thus allowing the purchase in the future of up to an aggregate of 12.0 million shares of the Corporation s common stock. The shares may be repurchased from time to time in open market purchases, and would be held as treasury shares and used for general corporate purposes. Since authorization under the buy-back program was last increased to 12.0 million shares in mid- 1999, the Corporation has repurchased a total of approximately 11.5 million shares. / / /