X0306 4 2021-07-01 0 0001564406 Oak Street Health, Inc. OSH 0001819292 CLEM BRIAN C/O OAK STREET HEALTH, INC. 30 W. MONROE STREET, SUITE 1200 CHICAGO IL 60603 0 1 0 0 President, Clinical Operations Common Stock, $0.001 par value 2021-07-01 4 S 0 7844 58.315 D 599934 D Common Stock, $0.001 par value 2021-07-01 4 S 0 2156 58.713 D 597778 D Common Stock, $0.001 par value 48 D The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan previously adopted by the Reporting Person. The Reporting Person undertakes to provide to Oak Street Health, Inc., any security holder of Oak Street Health, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each price within the ranges set forth in footnotes (2) and (3) to this Form 4. Transactions within a $1.00 price range are reported in accordance with the June 25th 2008 SEC No-Action letter. Minimum price was $57.62 and maximum price was $58.61. Transactions within a $1.00 price range are reported in accordance with the June 25th 2008 SEC No-Action letter. Minimum price was $58.64 and maximum price was $58.78. /s/ Robert Guenthner, as attorney-in-fact for Brian Clem 2021-07-02