Clean Harbors (NYSE: CLH) co-CEO logs tax withholding and share forfeiture

Rhea-AI Filing Summary

CLEAN HARBORS INC co-CEO Eric W. Gerstenberg reported routine compensation-related share dispositions. On March 13, 2026, 977 shares of common stock were withheld to cover tax liabilities upon vesting. On the same date, 2,166 shares of restricted stock were forfeited because the company did not achieve performance targets under its Long Term Equity Incentive Program. After these transactions, Gerstenberg directly owned 39,877 shares of common stock.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider GERSTENBERG ERIC W

Role CO-CEO

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	977	$288.93	$282K
Disposition	Common Stock	2,166	$0.00	--

Holdings After Transaction: Common Stock — 42,043 shares (Direct)

Footnotes (1)

1. Payment of tax liability by withholding of securities incident to vesting of securities in accordance with Rule 16b3. Shares of restricted stock forfeited due to the Company not achieving performance targets under its Long Term Equity Incentive Program.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

GERSTENBERG ERIC W

(Last) (First) (Middle)

C/O CLEAN HARBORS ENVIRON. SERVICES INC.

42 LONGWATER DRIVE

(Street)

NORWELL MA 02061

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
CLEAN HARBORS INC [ CLH ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	CO-CEO

3. Date of Earliest Transaction (Month/Day/Year)
03/13/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	03/13/2026		F		977(1)	D	$288.93	42,043	D
Common Stock	03/13/2026		D		2,166(2)	D	$0	39,877	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Payment of tax liability by withholding of securities incident to vesting of securities in accordance with Rule 16b3.

2. Shares of restricted stock forfeited due to the Company not achieving performance targets under its Long Term Equity Incentive Program.

	/s/ Eric W. Gerstenberg	03/17/2026
	** 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 4 (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.

FAQ

What insider transactions did CLEAN HARBORS (CLH) report for Eric Gerstenberg?

CLEAN HARBORS reported that co-CEO Eric W. Gerstenberg had 977 shares withheld for tax liabilities and 2,166 shares of restricted stock forfeited due to missed performance targets. These are compensation-related, non-market transactions disclosed in a Form 4 filing.

Were the CLEAN HARBORS (CLH) Form 4 transactions open-market buys or sells?

No, the Form 4 shows no open-market buys or sells. One transaction was 977 shares withheld to pay tax obligations on vesting, and another was 2,166 restricted shares forfeited back to the company after performance targets were not met.

How many CLEAN HARBORS (CLH) shares does Eric Gerstenberg hold after these transactions?

After the reported Form 4 transactions, Eric W. Gerstenberg directly holds 39,877 shares of CLEAN HARBORS common stock. This figure reflects his remaining direct ownership following the tax withholding and restricted stock forfeiture on March 13, 2026.

Why were 2,166 CLEAN HARBORS (CLH) restricted shares forfeited by the co-CEO?

The 2,166 restricted shares were forfeited because CLEAN HARBORS did not achieve performance targets under its Long Term Equity Incentive Program. According to the filing, these shares were returned to the company rather than sold on the open market.

What does the tax withholding transaction in the CLEAN HARBORS (CLH) Form 4 mean?

The tax withholding transaction shows 977 shares withheld to satisfy tax liabilities when stock awards vested. Instead of paying cash taxes, shares are retained by the company at the reported price, which is a common, non-market mechanism under Rule 16b-3.