Joe P. Ross - 01 Apr 2026 Form 4 Insider Report for Custom Truck One Source, Inc. (CTOS)

Reporting relationship: President - Sales
Issuer ticker: CTOS
Reported as of: 01 Apr 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 03 Apr 2026, 18:07:14 UTC
Prior SEC filing: 26 Mar 2026
Source filing: View source filing
Reporting owner signature: By: /s/ Paul M. Jolas, Attorney-in-fact

Key filing fact

Joe P. Ross filed Form 4 for Custom Truck One Source, Inc. (CTOS) on 03 Apr 2026.

Key facts

This page summarizes Joe P. Ross's Form 4 filing for Custom Truck One Source, Inc. (CTOS).
5 reported transactions and 3 derivative rows are listed below.
Accepted by SEC: 03 Apr 2026, 18:07.

Change

Previous filing in this sequence was filed on 26 Mar 2026.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001852519 Primary reporting owner

Ross Joe P.

Relationship: President - Sales
Address: 7701 INDEPENDENCE AVE, KANSAS CITY
Signature: By: /s/ Paul M. Jolas, Attorney-in-fact
Signature date: 03 Apr 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

CTOS transaction

Common Stock

Options Exercise

Transaction value
Shares: +75,000
Change %: +22%
Price: $0.000000^*
Shares after: 411,281
Date: 01 Apr 2026
Ownership: Direct
Footnotes: F1

CTOS transaction

Common Stock

Tax liability

Transaction value
Shares: -33,788
Change %: -8.2%
Price: $6.62^*
Shares after: 377,493
Date: 01 Apr 2026
Ownership: Direct
Footnotes: F2

CTOS holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 282,449
Date: 01 Apr 2026
Ownership: By Joseph P. Ross Holding Company, LLC

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

CTOS transaction Derivative

Restricted Stock Unit

Options Exercise

Transaction value
Shares: -50,000
Change %: -50%
Price: $0.000000^*
Shares after: 50,000
Date: 01 Apr 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 50,000
Exercise price
Footnotes: F1, F3

CTOS transaction Derivative

Restricted Stock Unit

Options Exercise

Transaction value
Shares: -25,000
Change %: -25%
Price: $0.000000^*
Shares after: 75,000
Date: 01 Apr 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 25,000
Exercise price
Footnotes: F1, F4

CTOS transaction Derivative

Restricted Stock Unit

Award

Transaction value
Shares: +100,000
Change %
Price: $0.000000^*
Shares after: 100,000
Date: 01 Apr 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 100,000
Exercise price
Footnotes: F1, F5

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 5 footnotes

Footnote F1

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

Footnote F2

Shares withheld to satisfy tax obligations arising out of vesting of the Reporting Person's restricted stock units.

Footnote F3

The restricted stock units vest in four equal annual installments beginning on April 1, 2024.

Footnote F4

The restricted stock units vest in four equal annual installments beginning on April 1, 2026.

Footnote F5

The restricted stock units vest in four equal annual installments beginning on April 1, 2027, subject to continued service on the applicable vesting date and potential partial acceleration upon the achievement of certain corporate milestones.