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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 8-K
CURRENT REPORT
Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934
Date of report (Date of earliest event reported): May 3, 2023
ESS TECH, INC.
(Exact Name of Registrant as Specified in Charter)
Delaware001-3952598-1550150
(State or other jurisdiction
of incorporation)
(Commission
File Number)
(I.R.S. Employer
Identification Number)
26440 SW Parkway Ave., Bldg. 83
Wilsonville, Oregon
 97070
(Address of principal executive offices) (Zip code)
(855) 423-9920
(Registrant’s telephone number, including area code)
Not Applicable
(Former name or former address, if changed since last report)
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the Registrant under any of the following provisions:
☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
Securities registered pursuant to Section 12(b) of the Act:
Title of each class
Trading
Symbol(s)
Name of each exchange
on which registered
Common Stock, $0.0001 par value per shareGWHThe New York Stock Exchange
Warrants, each whole warrant exercisable for one share of common stock at an exercise price of $11.50GWH.WThe New York Stock Exchange
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2).
Emerging growth company ☒
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐



Item 4.01. Changes in Registrant’s Certifying Accountant.
Engagement of New Independent Registered Public Accounting Firm
On May 2, 2023, upon the completion of a Request for Proposal, the Audit Committee of the Board of Directors of ESS Tech, Inc. (the “Company”) appointed KPMG LLP (“KPMG”) as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2023, effective immediately.
During the Company’s two most recent fiscal years ended December 31, 2022 and 2021, and the subsequent interim period from January 1, 2023 to May 2, 2023, neither the Company, nor anyone on the Company’s behalf, consulted with KPMG regarding either (i) the application of accounting principles to a specific transaction, either completed or proposed, or the type of audit opinion that might be rendered on the Company’s consolidated financial statements, and neither a written report nor oral advice was provided to the Company that KPMG concluded was an important factor considered by the Company in reaching a decision as to any accounting, auditing or financial reporting issue or (ii) any matter that was either the subject of a disagreement (within the meaning of Item 304(a)(1)(iv) of Regulation S-K and the related instructions) or a reportable event (as described in Item 304(a)(1)(v) of Regulation S-K).
As previously disclosed in the Company’s Form 8-K dated April 14, 2023, Ernst & Young LLP (“EY”), the Company’s predecessor auditor, informed the Company that it had declined to stand for re-election as the Company’s registered public accounting firm for the audit of the fiscal year ended December 31, 2023. A copy of EY’s letter dated May 3, 2023 referring to its letter dated April 14, 2023, stating that they agree with the statements made in such Form 8-K is attached hereto as Exhibit 16.1.
Item 9.01. Financial Statements and Exhibits.
(d) Exhibits.
Exhibit Number
Description
16.1
104
Cover Page Interactive Data File (embedded within the Inline XBRL document)
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SIGNATURE
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, hereunto duly authorized.
Dated: May 3, 2023
ESS TECH, INC.
By:/s/ Anthony Rabb
Name:Anthony Rabb
Title:Chief Financial Officer

May 3, 2023
Securities and Exchange Commission
100 F Street, N.E.
Washington, DC 20549

Ladies and Gentlemen:

Refer to our letter issued with Item 4.01 of Form 8-K dated 14 April 2023 of ESS Tech, Inc.

/s/ Ernst & Young LLP