SEC FORM 3

SEC FORM 3 SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

ONEX CORP

(Last)

(First)

(Middle)

161 BAY STREET

P.O. BOX 700

(Street)

TORONTO

M5J 2S1

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
06/15/2023

3. Issuer Name and Ticker or Trading Symbol
ATI Physical Therapy, Inc. [ ATIP ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

Director	X	10% Owner
Officer (give title below)		Other (specify below)

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Series A Preferred Stock	20,000	I	See Footnote⁽¹⁾⁽⁸⁾
Series B Preferred Stock	9,126	I	See Footnote⁽²⁾⁽⁸⁾

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivative Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
Series I Warrants (right to acquire)	⁽³⁾	⁽³⁾	Class A Common Stock	13,240	⁽³⁾	I	See Footnotes⁽³⁾⁽⁸⁾
Series II Warrants (right to acquire)	⁽⁴⁾	⁽⁴⁾	Class A Common Stock	14,634	⁽⁴⁾	I	See Footnotes⁽⁴⁾⁽⁸⁾
Convertible PIK Notes	⁽⁵⁾⁽⁶⁾⁽⁷⁾	⁽⁵⁾⁽⁶⁾⁽⁷⁾	Class A Common Stock	730,166⁽⁷⁾	⁽⁵⁾⁽⁶⁾⁽⁷⁾	I	See Footnotes⁽⁵⁾⁽⁶⁾⁽⁷⁾⁽⁸⁾

1. Name and Address of Reporting Person^*

ONEX CORP

(Last)

(First)

(Middle)

161 BAY STREET

P.O. BOX 700

(Street)

TORONTO

M5J 2S1

(City)

(State)

(Zip)

1. Name and Address of Reporting Person^*

OMI Partnership Holdings Ltd.

(Last)

(First)

(Middle)

161 BAY STREET

P.O. BOX 700

(Street)

TORONTO

M5J 2S1

(City)

(State)

(Zip)

1. Name and Address of Reporting Person^*

Onex Capital Solutions GP, LLC

(Last)

(First)

(Middle)

161 BAY STREET

P.O. BOX 700

(Street)

TORONTO

M5J 2S1

(City)

(State)

(Zip)

1. Name and Address of Reporting Person^*

Onex Capital Solutions GP, LP

(Last)

(First)

(Middle)

161 BAY STREET

P.O. BOX 700

(Street)

TORONTO

M5J 2S1

(City)

(State)

(Zip)

1. Name and Address of Reporting Person^*

Onex Capital Solutions Holdings, LP

(Last)

(First)

(Middle)

161 BAY STREET

P.O. BOX 700

(Street)

TORONTO

M5J 2S1

(City)

(State)

(Zip)

1. Name and Address of Reporting Person^*

SCHWARTZ GERALD W

(Last)

(First)

(Middle)

161 BAY STREET

P.O. BOX 700

(Street)

TORONTO

M5J 2S1

(City)

(State)

(Zip)

Explanation of Responses:

1. Reflects shares of Series A Preferred Stock of the Issuer held by Onex Capital Solutions Holdings, LP ("OCS").

2. Reflects shares of Series B Preferred Stock of the Issuer held by OCS.

3. Reflects warrants to acquire shares of Class A Common Stock of the Issuer ("Common Stock") held by OCS ("Series I Warrants"). The Series I Warrants may be exercised by at any time prior to their expiration on February 24, 2027. The exercise price of the Series I Warrants is $150.00 per share.

4. Reflects warrants to acquire shares of Common Stock held by OCS ("Series II Warrants"). The Series II Warrants may be exercised at any time prior to their expiration on February 24, 2027. The exercise price of the Series II Warrants is $0.50 per share.

5. Reflects senior second lien secured convertible PIK notes held by OCS ("Notes"). The aggregate principal amount of the Notes is $9,127,076.88, and the Notes accrue interest at a rate of 8.00% per annum. Subject to earlier conversion in accordance with their terms, the Notes will become due and payable on August 24, 2028 (the "Maturity Date") in an amount equal to the principal amount of the Notes outstanding on such date (plus any accrued but unpaid interest thereon).

6. All or any portion of the Notes may be converted at the election of the Reporting Persons at any time prior to the close of business on the business day immediately preceding the Maturity Date into a number of shares of Common Stock, determined by dividing (a) the outstanding balance of the principal amount of the Notes being converted (together with the accrued but unpaid interest thereon) as of the applicable conversion date, by (b) a conversion price of $12.50, which such conversion price is subject to certain anti-dilution adjustments in accordance with their terms.

7. This number represents the number of shares of Common Stock issuable upon conversion of the Notes if the Reporting Persons elect to convert the Notes based on the principal amount of the Notes (as described in footnote (5) above) and the conversion price (as described in footnote (6) above).

8. Onex Corporation ("Onex") owns all of the equity of OMI Partnership Holdings Ltd. ("OMI"), which is the sole member of Onex Capital Solutions GP, LLC ("OCS GP LLC"), which is the general partner of Onex Capital Solutions GP, LP ("OCS GP LP"), which is the general partner of OCS. Accordingly, Onex may be deemed to beneficially own the reported securities held by OCS. [Gerald W. Schwartz, the Chairman of Onex, indirectly owns shares representing a majority of the voting rights of the shares of Onex, and as such may be deemed to beneficially own all of the reported securities beneficially owned by Onex.] Each Reporting Person disclaims beneficial ownership of the reported securities except to the extent of his or its pecuniary interest therein.

Remarks:

Exhibit 99 - Joint Filer Statement

	Onex Corporation, by: /s/ Andrea Daly, Managing Director--General Counsel	06/26/2023
	OMI Partnership Holdings Ltd., by: /s/ Steve Gutman, Authorized Signatory	06/26/2023
	Onex Capital Solutions GP, LLC, by: /s/ Steve Gutman, General Counsel	06/26/2023
	Onex Capital Solutions GP, LP, by: /s/ Onex Capital Solutions GP, LLC, its general partner	06/26/2023
	Onex Capital Solutions Holdings, LP, by: /s/ Onex Capital Solutions GP, LP, its general partner and Onex Capital Solutions GP, LLC, its general partner	06/26/2023
	Gerald W. Schwartz, by: Andrea Daly, Attorney-in-fact	06/26/2023
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

SEC Form 3: New insider Onex Corp claimed ownership of 20,000 units of Series A Preferred Stock and claimed ownership of 9,126 units of Series B Preferred Stock