X0303 4 2010-02-22 0000073124 NORTHERN TRUST CORP NTRS 0001322843 Blake Aileen B 50 SOUTH LASALLE STREET CHICAGO IL 60603 0 1 0 0 EVP and Controller Common Stock 2010-02-22 4 F 0 231 54.445 D 6805 D Common Stock 5067 D Common Stock 93 I 401(k) Represents stock units payable automatically on a 1-for-1 basis in shares of the Corporation's common stock. On February 22, 2010, 740 already reported and vested stock units, granted February 21, 2006, were distributed to the reporting person. 509 stock units were distributed to the reporting person as shares of common stock (NTRS) and 231 stock units were withheld in payment of Federal, State and Medicare taxes. This total includes the net shares delivered to the reporting person upon the vesting of an already reported restricted stock unit award as referred to in Footnote 2. as of 12-31-09 Paul A. Bernacki Attorney-In-Fact for Aileen B. Blake 2010-05-25