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

Apr 2, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Custom Truck One Source, Inc. (CTOS)
CIK: 0001709682
Period of Report: 2025-03-31

Reporting Person: Heinberg Marshall (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-03-31	Common Stock	M	39993	—	Acquired	352202	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-03-31	Restricted Stock Unit	$	M	39993	Disposed		Common Stock (39993)	Direct
2025-04-01	Restricted Stock Unit	$	A	48346	Acquired		Common Stock (48346)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	120000	Indirect

Footnotes

F1: Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock.

F2: The restricted stock units vested in full on March 31, 2025.

F3: The restricted stock units will vest on March 31, 2026 and have no expiration date.