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^*

Blackstone Holdings III L.P.

(Last)

(First)

(Middle)

C/O CUSTOM TRUCK ONE SOURCE, INC.

7701 INDEPENDENCE AVENUE

(Street)

KANSAS CITY

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
04/01/2021

3. Issuer Name and Ticker or Trading Symbol
Custom Truck One Source, Inc. [ NSCO ]

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

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

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)
Common Stock	2,932,195	I	See Footnotes⁽¹⁾⁽⁸⁾⁽⁹⁾⁽¹⁰⁾⁽¹¹⁾⁽¹²⁾
Common Stock	3,622,088	I	See Footnotes⁽²⁾⁽⁸⁾⁽⁹⁾⁽¹⁰⁾⁽¹¹⁾⁽¹²⁾
Common Stock	351,593	I	See Footnotes⁽³⁾⁽⁸⁾⁽⁹⁾⁽¹⁰⁾⁽¹¹⁾⁽¹²⁾
Common Stock	179,835	I	See Footnotes⁽⁴⁾⁽⁸⁾⁽⁹⁾⁽¹⁰⁾⁽¹¹⁾⁽¹²⁾
Common Stock	3,492,069	I	See Footnotes⁽⁵⁾⁽⁸⁾⁽⁹⁾⁽¹⁰⁾⁽¹¹⁾⁽¹²⁾
Common Stock	3,576,281	I	See Footnotes⁽⁶⁾⁽⁸⁾⁽⁹⁾⁽¹⁰⁾⁽¹¹⁾⁽¹²⁾
Common Stock	17,360	I	See Footnotes⁽⁷⁾⁽⁸⁾⁽⁹⁾⁽¹⁰⁾⁽¹¹⁾⁽¹²⁾

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)

1. Name and Address of Reporting Person^*

Blackstone Holdings III L.P.

(Last)

(First)

(Middle)

C/O CUSTOM TRUCK ONE SOURCE, INC.

7701 INDEPENDENCE AVENUE

(Street)

KANSAS CITY

(City)

(State)

(Zip)

1. Name and Address of Reporting Person^*

Blackstone Group Inc

(Last)

(First)

(Middle)

C/O THE BLACKSTONE GROUP INC.

345 PARK AVENUE

(Street)

NEW YORK

10154

(City)

(State)

(Zip)

1. Name and Address of Reporting Person^*

Blackstone Group Management L.L.C.

(Last)

(First)

(Middle)

C/O THE BLACKSTONE GROUP INC.

345 PARK AVENUE

(Street)

NEW YORK

10154

(City)

(State)

(Zip)

1. Name and Address of Reporting Person^*

SCHWARZMAN STEPHEN A

(Last)

(First)

(Middle)

C/O THE BLACKSTONE GROUP INC.

345 PARK AVENUE

(Street)

NEW YORK

10154

(City)

(State)

(Zip)

Explanation of Responses:

1. Reflects shares of common stock, par value $0.0001 per share ("Common Stock"), of Custom Truck One Source, Inc. (the "Issuer") directly held by Blackstone Energy Partners NQ L.P. ("BEP NQ").

2. Reflects shares of Common Stock directly held by BEP CTOS Holdings L.P. ("BEP CTOS").

3. Reflects shares of Common Stock directly held by Blackstone Energy Family Investment Partnership SMD L.P. ("BE SMD").

4. Reflects shares of Common Stock directly held by Blackstone Energy Family Investment Partnership NQ ESC L.P. ("BE NQ").

5. Reflects shares of Common Stock directly held by Blackstone Capital Partners VI-NQ L.P. ("BCP VI-NQ").

6. Reflects shares of Common Stock directly held by BCP CTOS Holdings L.P. ("BCP CTOS").

7. Reflects shares of Common Stock directly held by Blackstone Family Investment Partnership VI-NQ ESC L.P. ("BE FIP").

8. Blackstone Energy Management Associates NQ L.L.C. ("BEMA") is the general partner of BEP NQ and BEP CTOS. Blackstone EMA-NQ L.L.C. ("BEMA NQ") is the managing member of BEMA. BEP Side-by-Side GP NQ L.L.C. ("BEP GP") is the general partner of BE NQ. Blackstone Management Associates VI-NQ L.L.C. ("BMA NQ") is the general partner of BCP VI-NQ and BCP CTOS. BMA VI-NQ L.L.C. ("BMA VI-NQ") is the managing member of BMA NQ. Blackstone Family GP L.L.C. ("BS GP") is the general partner of BE SMD. BS GP is wholly-owned by Blackstone's senior managing directors and controlled by its founder, Stephen A. Schwarzman. BCP VI-NQ Side-by-Side GP L.L.C. ("BCP GP") is the general partner of BE FIP.

9. Blackstone Holdings III L.P. ("Holdings III") is the sole member of each of BEMA NQ, BEP GP and BMA VI-NQ. The general partner of Holdings III is Blackstone Holdings III GP L.P. ("Holdings III GP") The general partner of Holdings III GP is Blackstone Holdings III GP Management L.L.C ("Holdings III GP Management"). Blackstone Holdings II L.P. ("Holdings II") is the sole member of BCP GP. Blackstone Holdings I/II GP L.L.C. ("Holdings I/II GP") is the general partner of Holdings II. The Blackstone Group Inc. ("Blackstone") is the sole member of Holdings III GP Management and Holdings I/II GP. The sole holder of the Series II preferred stock of Blackstone is Blackstone Group Management L.L.C. ("BS Group Management"). BS Group Management is wholly-owned by Blackstone's senior managing directors and controlled by its founder, Stephen A. Schwarzman.

10. Information with respect to each of the Reporting Persons is given solely by such Reporting Person, and no Reporting Person has responsibility for the accuracy or completeness of information supplied by another Reporting Person.

11. Due to the limitations of the electronic filing system certain Reporting Persons are filing a separate Form 3.

12. Each of the Reporting Persons (other than to the extent it directly holds securities reported herein) disclaims beneficial ownership of the securities held by the other Reporting Persons, except to the extent of such Reporting Person's pecuniary interest therein, and, pursuant to Rule 16a-1(a)(4) under the Securities Exchange Act of 1934 (the "Exchange Act"), each of the Reporting Persons (other than to the extent it directly holds securities reported herein) states that the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of all of the reported securities for purposes of Section 16 or for any other purpose or that the Reporting Persons are subject to Section 16 of the Exchange Act.

Remarks:

On April 1, 2021, the transaction pursuant to which the Issuer and NESCO Holdings II, Inc., a subsidiary of the Issuer agreed to acquire 100% of the partnership interests of Custom Truck One Source, L.P. (the "Acquisition") closed. On April 1, 2021, in connection with the closing of the Acquisition, the Issuer, an affiliate of Platinum Equity Advisors, LLC, certain affiliates of Blackstone, certain affiliates of Energy Capital Partners, Capitol Acquisition Management IV, LLC and Capital Acquisition Founder IV, LLC and certain other stockholders of the Issuer entered into an Amended and Restated Stockholders' Agreement (the "Stockholders' Agreement"). By virtue of the Stockholders' Agreement, the Reporting Persons and the other persons party thereto may each be deemed to be a member of a "group" for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), that beneficially owns more than 10% of the outstanding shares of Common Stock. However, the filing of this Form 3 shall not be deemed an admission that the Reporting Persons and such other persons are members of any such group. Form 3 of 3

	BLACKSTONE ENERGY PARTNERS NQ L.P., By: Blackstone Energy Management Associates NQ L.L.C., its general partner, By: Blackstone EMA-NQ L.L.C., its managing member	04/12/2021
	THE BLACKSTONE GROUP INC.	04/12/2021
	BLACKSTONE GROUP MANAGEMENT L.L.C.	04/12/2021
	Stephen A. Schwarzman	04/12/2021
	** 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: L.P. Iii Holdings Blackstone claimed ownership of 14,171,421 units of Common Stock