[Form 4] ESS Tech, Inc. Insider Trading Activity

Rhea-AI Filing Summary

ESS Tech, Inc. (GWH) reported an insider equity transaction by its Interim CFO on 11/20/2025. The filing shows that 1,299 shares of common stock were withheld by the company when restricted stock units (RSUs) vested in order to cover tax withholding obligations at a price of $2.4 per share. After this withholding, the reporting person beneficially owned 27,655 shares of ESS Tech common stock, including RSUs, each representing a contingent right to receive one share upon vesting.

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^*

Suhadolnik Kate Eileen

(Last) (First) (Middle)

C/O ESS TECH, INC.

26440 SW PARKWAY AVE., BLDG. 83

(Street)

WILSONVILLE OR 97070

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
ESS Tech, Inc. [ GWH ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Interim CFO

3. Date of Earliest Transaction (Month/Day/Year)
11/20/2025

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	11/20/2025		F		1,299(1)	D	$2.4	27,655	D(2)

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. The reported shares were withheld by the Issuer upon vesting of RSUs to satisfy tax withholding obligations.

2. A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

Remarks:

	/s/ Kate Suhadolnik	11/20/2025
	** 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 transaction did ESS Tech (GWH) report in this Form 4?

The Form 4 reports that ESS Tech's Interim CFO had 1,299 shares of common stock withheld on 11/20/2025 to satisfy tax withholding obligations upon the vesting of restricted stock units (RSUs).

Who is the reporting person in the ESS Tech (GWH) Form 4 filing?

The reporting person is an Officer of ESS Tech, Inc., serving as the company's Interim CFO at the time of the reported transaction.

How many ESS Tech (GWH) shares does the Interim CFO own after the transaction?

Following the reported tax withholding transaction, the Interim CFO beneficially owned 27,655 shares of ESS Tech common stock, including RSUs that each represent a contingent right to receive one share.

What was the purpose of withholding 1,299 ESS Tech (GWH) shares?

The 1,299 shares were withheld by ESS Tech when RSUs vested in order to satisfy the reporting person's tax withholding obligations, rather than being sold on the open market.

What are the RSUs referenced in the ESS Tech (GWH) Form 4?

The filing explains that a portion of the reported securities are RSUs, with each RSU representing a contingent right to receive one share of ESS Tech common stock.

Is this ESS Tech (GWH) Form 4 filed for one or multiple reporting persons?

The Form 4 is indicated as being filed by one reporting person, not a group or multiple insiders.