On April 28, 2009, Northern Trust Corporation (the "Company") entered into an Underwriting Agreement (the "Common Stock Underwriting Agreement") with Goldman, Sachs & Co. and Morgan Stanley & Co. Incorporated, as representatives of the several underwriters listed therein (the "Common Stock Underwriters") with respect to the offering and sale of 17,250,000 shares of common stock of the Company, par value $1.66 2/3 per share (the "Offered Shares"), including 2,250,000 shares pursuant to the option granted to the Common Stock Underwriters to cover over-allotments. On April 28, 2009, the Common Stock Underwriters exercised in full their option to purchase the additional 2,250,000 shares. On May 1, 2009, the public offering and sale of all the Offered Shares was consummated.

Certain of the Common Stock Underwriters and their respective affiliates have, from time to time, performed, and may in the future perform, various financial advisory and investment banking services for the Company, including participating in the public offering of Notes, for which they received or will receive customary fees and expenses.

On April 28, 2009, the Company also entered into an Underwriting Agreement (the "Notes Underwriting Agreement," and, together with the Common Stock Underwriting Agreement, the "Agreements") with Goldman, Sachs & Co. and Morgan Stanley & Co. Incorporated, as representatives of the several underwriters listed therein (the "Notes Underwriters") with respect to the offering and sale of $500 million of 4.625% Notes due 2014 (the "Notes"). The Notes will be issued under an Indenture dated August 15, 2006, between the Company and The Bank of New York Mellon Trust Company, N.A. (as successor in interest to JPMorgan Chase Bank, N.A.), as trustee. On May 1, 2009, the public offering and sale of the Notes was consummated.

Certain of the Notes Underwriters and their respective affiliates have, from time to time, performed, and may in the future perform, various financial advisory and investment banking services for the Company, including participating in the public offering of Offered Shares, for which they received or will receive customary fees and expenses. In addition, the Company's broker-dealer subsidiary has referral agreements with certain of the Notes Underwriters under which it may refer securities underwriting opportunities to those underwriters, for which it would receive a referral fee.

The Agreements contain customary representations, warranties and covenants that are valid as between the parties and as of the date of entering such agreements and are not factual information to investors about the Company.

The offerings of the Notes and the Offered Shares were registered under the Securities Act of 1933, as amended, pursuant to the Company's shelf registration statement on Form S-3 (File No. 333-152678). The above descriptions of the Common Stock Underwriting Agreement and the Notes Underwriting Agreement are qualified in their entirety by reference to the full text of the respective agreement. Copies of the Common Stock Underwriting Agreement, the Notes Underwriting Agreement and the Form of Note are incorporated herein by reference and are attached to this Report on Form 8-K as Exhibits 1.1, 1.2 and 4, respectively.

(d) Exhibits.

Exhibit 1.1   Common Stock Underwriting Agreement, dated April 28, 2009, among
              Northern Trust Corporation, Goldman, Sachs & Co. and Morgan Stanley &
              Co. Incorporated as representatives of the several underwriters
              listed therein

Exhibit 1.2   Notes Underwriting Agreement, dated April 28, 2009, among Northern
              Trust Corporation, Goldman, Sachs & Co. and Morgan Stanley & Co.
              Incorporated as representatives of the several underwriters listed
              therein

Exhibit 4     Form of 4.625% Note due 2014