Custom Truck One Source, Inc. — Director's Dealing 2025

Feb 3, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Custom Truck One Source, Inc. (CTOS)
CIK: 0001709682
Period of Report: 2025-01-30

Reporting Person: PE One Source Holdings, LLC (10% Owner)
Reporting Person: Platinum Equity Partners V, L.P. (10% Owner)
Reporting Person: Platinum Equity Partners V, LLC (10% Owner)
Reporting Person: Platinum Equity Investment Holdings V, LLC (10% Owner)
Reporting Person: Platinum Equity Investment Holdings V Manager, LLC (10% Owner)
Reporting Person: Platinum Equity InvestCo, L.P. (10% Owner)
Reporting Person: Platinum InvestCo (Cayman), LLC (10% Owner)
Reporting Person: Platinum Equity Investment Holdings IC (Cayman), LLC (10% Owner)
Reporting Person: Platinum Equity Investment Holdings, LLC (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-01-30	Common Stock	P	8143635	$4.00	Acquired	156743635	Indirect

Footnotes

F1: PE One Source Holdings, LLC ("PE One Source") is the record holder of the securities reported herein. Tom Gores is the manager of Platinum Equity, LLC, which is the sole member of Platinum Equity Investment Holdings, LLC, which is the sole member of Platinum Equity Investment Holdings IC (Cayman), LLC, which is the general partner of Platinum Equity InvestCo, L.P., which is the sole member of Platinum Equity Investment Holdings V, LLC, which is the sole member of Platinum Equity Partners V, LLC, which is the general partner of Platinum Equity Partners V, L.P., which is the general partner of Platinum Equity Capital Partners V, L.P., which holds a majority of the outstanding equity of PE One Source.

F2: Additionally, Platinum Equity, LLC is also the sole member of Platinum Equity Investment Holdings V Manager, LLC, which is the sole manager of Platinum Equity Investment Holdings V, LLC. Platinum Equity, LLC and Tom Gores together hold a controlling interest in Platinum InvestCo (Cayman), LLC, which holds a controlling interest in Platinum Equity InvestCo, L.P. By virtue of these relationships, each of these entities and Mr. Gores may be deemed to share beneficial ownership of the securities held of record by PE One Source. Each of these entities and Mr. Gores disclaim any such beneficial ownership except to the extent of their pecuniary interests therein.