X0508 4/A 2022-08-15 2022-08-17 0001815849 ATI Physical Therapy, Inc. ATIP 0001307171 Parisi James E. C/O ATI PHYSICAL THERAPY 790 REMINGTON BOULEVARD BOLINGBROOK IL 60440 true false Class A Common Stock 2022-08-15 4 P 0 26000 0.97 A 69356 D Class A Common Stock 2022-08-17 4 P 0 26000 0.96 A 95356 D Class A Common Stock 7791 D Stock Option (right to buy) Class A Common Stock 1630 D The Form 4 filed on August 17, 2022 and on August 19, 2022 incorrectly referenced code "A"; the correct code is "P". The total beneficial ownership reflected on the Form 4 filed on August 19, 2022 is being amended to correct an administrative error. As of June 14, 2023, the issuer effected a reverse stock split (the "Reverse Split") of its Class A Common Stock at a ratio of 1-for-50, resulting in every 50 shares owned by the reporting person to be combined into one share of Class A Common Stock. Represents aggregate beneficial ownership following the Reverse Split of Issuer's Class A Common Stock as of February 23, 2024. Represents the aggregate amount of all options previously granted as reflected on Form 4 filed November 26, 2021 and March 9, 2022 (together, the "Option Form 4 Filings"). The options have been adjusted to reflect the Reverse Split. 899 of the options remain unvested, and vest pursuant to the schedules set-forth in the Option Form 4 Filings. /s/Erik Kantz as Attorney-in-Fact for Reporting Person 2024-02-23