Exhibit 1
Joint Filing Agreement
In accordance with Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them of a statement on Schedule 13D (including amendments thereto) with respect to shares of Class A Common Stock, $0.0001 par value per share, of ATI Physical Therapy, Inc., a Delaware corporation, and further agree that this Joint Filing Agreement be included as an Exhibit to such joint filings. In evidence thereof, the undersigned, being duly authorized, have executed this Joint Filing Agreement this 17th day of December 2024.
| ADVENT INTERNATIONAL L.P., |
| By: ADVENT INTERNATIONAL GP, LLC, GENERAL PARTNER |
/s/ Neil Crawford |
| Name: Neil Crawford |
| Title: Vice President of Finance |
| WILCO ACQUISITION, LP |
| By: WILCO GP, INC., GENERAL PARTNER |
/s/ John Maldonado |
| Name: John Maldonado |
| Title: President |
| WILCO GP, INC. |
/s/ John Maldonado |
| Title: President |
| ADVENT INTERNATIONAL GPE VII LIMITED PARTNERSHIP |
| ADVENT INTERNATIONAL GPE VII-B LIMITED PARTNERSHIP |
| ADVENT INTERNATIONAL GPE VII-C LIMITED PARTNERSHIP |
| ADVENT INTERNATIONAL GPE VII-D LIMITED PARTNERSHIP |
| ADVENT INTERNATIONAL GPE VII-F LIMITED PARTNERSHIP |
| ADVENT INTERNATIONAL GPE VII-G LIMITED PARTNERSHIP |
| By: GPE VII GP S.A.R.L., GENERAL PARTNER |
| By: ADVENT INTERNATIONAL GPE VII, LLC, MANAGER and |
/s/ Justin Nuccio |
| Name: Justin Nuccio |
| Title: Manager |
| By: ADVENT INTERNATIONAL L.P., MANAGER |
| By: ADVENT INTERNATIONAL GP, LLC, GENERAL PARTNER |
/s/ Neil Crawford |
| Name: Neil Crawford |
| Title: Vice President of Finance |
| ADVENT INTERNATIONAL GPE VII-A LIMITED PARTNERSHIP |
| ADVENT INTERNATIONAL GPE VII-E LIMITED PARTNERSHIP |
| ADVENT INTERNATIONAL GPE VII-H LIMITED PARTNERSHIP |
| By: GPE VII GP LIMITED PARTNERSHIP, GENERAL PARTNER |
| By: ADVENT INTERNATIONAL GPE VII, LLC, GENERAL PARTNER |
| By: ADVENT INTERNATIONAL L.P., MANAGER |
| By: ADVENT INTERNATIONAL GP, LLC, GENERAL PARTNER |
/s/ Neil Crawford |
| Name: Neil Crawford |
| Title: Vice President of Finance |
| ADVENT PARTNERS GPE VII 2014 LIMITED PARTNERSHIP |
| ADVENT PARTNERS GPE VII 2014 CAYMAN LIMITED PARTNERSHIP |
| ADVENT PARTNERS GPE VII—A 2014 LIMITED PARTNERSHIP |
| ADVENT PARTNERS GPE VII—A 2014 CAYMAN LIMITED PARTNERSHIP |
| ADVENT PARTNERS GPE VII CAYMAN LIMITED PARTNERSHIP |
| ADVENT PARTNERS GPE VII—B CAYMAN LIMITED PARTNERSHIP |
| ADVENT PARTNERS GPE VII LIMITED PARTNERSHIP |
| ADVENT PARTNERS GPE VII—A CAYMAN LIMITED PARTNERSHIP |
| ADVENT PARTNERS GPE VII—A LIMITED PARTNERSHIP |
| By: ADVENT INTERNATIONAL GPE VII, LLC, GENERAL PARTNER |
| By: ADVENT INTERNATIONAL L.P., MANAGER |
| By: ADVENT INTERNATIONAL GP, LLC, GENERAL PARTNER |
/s/ Neil Crawford |
| Name: Neil Crawford |
| Title: Vice President of Finance |
| GPE VII ATI CO-INVESTMENT (DELAWARE) LIMITED PARTNERSHIP |
| By: ADVENT INTERNATIONAL GPE VII, LLC, GENERAL PARTNER |
| By: ADVENT INTERNATIONAL L.P., MANAGER |
| By: ADVENT INTERNATIONAL GP, LLC, GENERAL PARTNER |
/s/ Neil Crawford |
| Name: Neil Crawford |
| Title: Vice President of Finance |
| GPE VII GP S.A.R.L. |
| By: ADVENT INTERNATIONAL GPE VII, LLC, |
| MANAGER and |
/s/ Justin Nuccio |
| Name: Justin Nuccio |
| Title: Manager |
| By: ADVENT INTERNATIONAL L.P., MANAGER |
| By: ADVENT INTERNATIONAL GP, LLC, GENERAL PARTNER |
/s/ Neil Crawford |
| Name: Neil Crawford |
| Title: Vice President of Finance |
| GPE VII GP LIMITED PARTNERSHIP |
| By: ADVENT INTERNATIONAL GPE VII, LLC, GENERAL PARTNER |
| By: ADVENT INTERNATIONAL L.P., MANAGER |
| By: ADVENT INTERNATIONAL GP, LLC, GENERAL PARTNER |
/s/ Neil Crawford |
| Name: Neil Crawford |
| Title: Vice President of Finance |
| ADVENT INTERNATIONAL GPE VII, LLC |
| By: ADVENT INTERNATIONAL L.P., MANAGER |
| By: ADVENT INTERNATIONAL GP, LLC, GENERAL PARTNER |
/s/ Neil Crawford |
| Name: Neil Crawford |
| Title: Vice President of Finance |
