Robert E. Rasmus - 23 Mar 2026 Form 4 Insider Report for Arq, Inc. (ARQ)

Reporting relationship: Chief Executive Officer, Director
Issuer ticker: ARQ
Reported as of: 23 Mar 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 25 Mar 2026, 08:00:11 UTC
Prior SEC filing: 12 Nov 2025
Next SEC filing: 23 Jul 2026
Source filing: View source filing
Reporting owner signature: /s/ Robert E. Rasmus

Key filing fact

Robert E. Rasmus filed Form 4 for Arq, Inc. (ARQ) on 25 Mar 2026.

Key facts

This page summarizes Robert E. Rasmus's Form 4 filing for Arq, Inc. (ARQ).
1 reported transaction and 0 derivative rows are listed below.
Accepted by SEC: 25 Mar 2026, 08:00.

Change

Previous filing in this sequence was filed on 12 Nov 2025.
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 0001555130 Primary reporting owner

Rasmus Robert E.

Relationship: Chief Executive Officer, Director
Address: C/O ARQ, INC., 8051 E MAPLEWOOD AVE STE 210, GREENWOOD VILLAGE
Signature: /s/ Robert E. Rasmus
Signature date: 25 Mar 2026

Reported non-derivative transactions

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

ARQ transaction

Common Stock

Tax liability

Transaction value
Shares: -845
Change %: -0.18%
Price: $2.27^*
Shares after: 479,937
Date: 23 Mar 2026
Ownership: Direct
Footnotes: F1

ARQ holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 70,718
Date: 23 Mar 2026
Ownership: By RER Investments LLC
Footnotes: F2

ARQ holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 527,779
Date: 23 Mar 2026
Ownership: By RER Legacy Investments II LLC.
Footnotes: F3

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

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

Reflects the withholding of shares of the Issuer's common stock to satisfy tax withholding obligations in connection with the vesting of restricted stock awards ("RSAs") on March 23, 2026.

Footnote F2

The shares of Common Stock reported on this row are held by RER Investments LLC ("RER Investments"). Mr. Rasmus, the Chief Executive Officer and a Director of the Issuer, is the ultimate control person of RER Investments, and an indirect beneficial owner of these shares. Mr. Rasmus disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

Footnote F3

The shares of Common Stock reported on this row are held by RER Legacy Investments II LLC ("RER Legacy"). Mr. Rasmus, the Chief Executive Officer and a Director of the Issuer, is the ultimate control person of RER Legacy, and an indirect beneficial owner of these shares. Mr. Rasmus disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.