Form 8-K

8-K — ESS Tech, Inc.

Accession: 0001819438-26-000065

Filed: 2026-07-17

Period: 2026-07-16

CIK: 0001819438

SIC: 3690 (MISCELLANEOUS ELECTRICAL MACHINERY, EQUIPMENT & SUPPLIES)

Item: Entry into a Material Definitive Agreement

Item: Financial Statements and Exhibits

Documents

8-K — wk-20260716.htm (Primary)

EX-1.1 (exhibit11-amendmentno1tosa.htm)

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8-K

8-K (Primary)

Filename: wk-20260716.htm · Sequence: 1

wk-20260716

0001819438False00018194382026-07-162026-07-16

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): July 16, 2026

ESS TECH, INC.

(Exact Name of Registrant as Specified in Charter)

Delaware 001-39525 98-1550150

(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 share GWH The 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 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

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 1.01 Entry into a Material Definitive Agreement.

On July 16, 2026, ESS Tech, Inc. (the “Company”) entered into an amendment to its Sales Agreement (the “Amendment Agreement”) for its “at the market offering” program (the “ATM Program”) to sell $75 million shares of the Company’s common stock (the “Shares”) which was previously entered into with Yorkville Ives & Co., LLC (formerly Yorkville Securities, LLC) (“Yorkville Ives”), BMO Capital Markets Corp. (“BMO”), Canaccord Genuity LLC (“Canaccord”), Needham & Company, LLC (“Needham”) and Stifel, Nicolaus & Company, Incorporated (“Stifel”) on November 13, 2025 (the “Original Sales Agreement”). Under the Amendment, the Company has (i) terminated the Original Sales Agreement with respect to BMO, Canaccord, Needham and Stifel; (ii) added Roth Capital Partners, LLC (“Roth”) as an additional sales agent under the Amended Sales Agreement (as defined below) and (iii) Roth has assumed the responsibilities of acting as a “qualified independent underwriter” within the meaning of Rule 5121 of the Financial Industry Regulatory Authority in connection with this offering, replacing Canaccord as “qualified independent underwriter” (collectively, the “Amendments”). The amended Original Sales Agreement is hereinafter referred to as the “Amended Sales Agreement.” In connection with the Amendments, the Company has filed an amendment to the prospectus supplement filed with the Securities and Exchange Commission (the “SEC”) on December 11, 2025 relating to the Company’s ATM Program.

The foregoing summary of the Amendment Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Amendment Agreement, a copy of which is filed as Exhibit 1.1 hereto and incorporated herein by reference. The provisions of the Original Sales Agreement and Amendment Agreement, including the representations and warranties contained therein, are not for the benefit of any party other than the parties to such Original Sales Agreement and Amendment Agreement and are not intended as a document for investors and the public to obtain factual information about the Company’s current state of affairs. Rather, investors and the public should look to other disclosures contained in the Company’s filings with the SEC.

This Current Report on Form 8-K shall not constitute an offer to sell or the solicitation of an offer to buy any Shares under the Amended Sales Agreement, nor shall there be any sale of such Shares in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. YA II PN, Ltd., an affiliate of Yorkville Ives, was a party to the Company’s Standby Equity Purchase Agreement, and an affiliate of Yorkville Ives is the lender under the Promissory Note between the Company and YA II PN, Ltd. Furthermore, Yorkville Ives and Roth and/or one of their respective affiliates may in the future provide certain commercial banking, financial advisory, and investment banking services in the ordinary course of business for the Company for which they will receive customary fees and commissions.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit

No.

1.1

Amendment No. 1 to Sales Agreement dated July 16, 2026, by and among ESS Tech, Inc., Yorkville Ives & Co., LLC and Roth Capital Partners, LLC

104 Cover Page Interactive Data File (embedded within the Inline XBRL document)

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: July 16, 2026

ESS TECH, INC.

By: /s/ Kate Suhadolnik

Name: Kate Suhadolnik

Title: Chief Financial Officer

EX-1.1

Filename: exhibit11-amendmentno1tosa.htm · Sequence: 2

Document

AMENDMENT NO. 1 TO SALES AGREEMENT

July 16, 2026

Yorkville Ives & Co., LLC

1012 Springfield Avenue

Mountainside, NJ 07092

Roth Capital Partners, LLC

888 San Clemente Drive, Suite 400

Newport Beach, CA 92660

Ladies and Gentlemen:

ESS Tech, Inc., a Delaware corporation (the “Company”) and Yorkville Ives & Co., LLC (formerly Yorkville Securities, LLC) (“Yorkville Ives”), are parties to that certain Sales Agreement dated November 13, 2025 (the “Original Agreement”). All capitalized terms not defined herein shall have the meanings ascribed to them in the Original Agreement. The Company and Yorkville Ives, together with Roth Capital Partners, LLC (“Roth”) desire to amend the Original Agreement as set forth in this Amendment No. 1 thereto (this “Amendment”; the Original Agreement and the Amendment, together the “Sales Agreement”) as follows:

1.The definitions of “Agent” and “Agents” in the first paragraph of the Original Agreement are hereby amended to include Roth and to remove each of BMO Capital Markets Corp., Canaccord Genuity LLC (“Canaccord”), Needham & Company, LLC and Stifel, Nicolaus & Company, Incorporated.

2.Section 14 of the Original Agreement is hereby amended to replace the Agents’ notice party information as follows:

“Yorkville Ives & Co., LLC

1012 Springfield Avenue

Mountainside, NJ 07092

Attention: Legal Department

Email: [***]

And

Roth Capital Partners, LLC

888 San Clemente Drive, Suite 400

Newport Beach, CA 92660

Attention: Capital Markets

Email: [***]

3.The Company hereby appoints Roth as, and Roth hereby confirms its agreement to render services as, a “qualified independent underwriter,” within the meaning of Section (f)(12) of Rule 5121 of the Financial Industry Regulatory Authority, Inc. (“FINRA”) with respect to the offering and sale of the Placement Shares. Roth, solely in its capacity as the qualified independent underwriter and not otherwise, shall be referred to in the Sales Agreement as the “QIU.” Roth hereby consents to the reference to it as set forth under the heading “Plan of Distribution (Conflicts of Interest)” in the Prospectus and any amendment or supplement thereto. For the avoidance of doubt, Canaccord shall no longer serve as the Company’s qualified independent underwriter upon the execution of this Amendment.

4.Schedules 1 and 2 of the Original Agreement and the Form of Representation Date Certificate Pursuant to Section 7(l) of the Original Agreement shall be replaced in their entirety with the versions attached hereto.

5.Pursuant to Section 9(v)(z) of the Original Agreement, the Company agrees to pay the fees and disbursements of Agents’ counsel in connection with the execution of this Amendment in an amount not to exceed $40,000.

6.From and after the date hereof, Roth shall be considered to be an Agent under the Original Agreement, as amended hereby, and agrees to be bound by the terms of the Original Agreement, as amended hereby.

7.Sections 18 and 19 of the Original Agreement are hereby incorporated into this Amendment. Except as specifically set forth herein, all other provisions of the Original Agreement shall remain in full force and effect.

8.This Amendment together with the Original Agreement (including all exhibits attached hereto) constitutes the entire agreement and supersedes all other prior and contemporaneous agreements and undertakings, both written and oral, among the parties hereto with regard to the subject matter hereof. Neither this Amendment nor any term hereof may be amended except pursuant to a written instrument executed by the Company and the Agents. In the event that any one or more of the provisions contained herein, or the application thereof in any circumstance, is held invalid, illegal or unenforceable as written by a court of competent jurisdiction, then such provision shall be given full force and effect to the fullest possible extent that it is valid, legal and enforceable, and the remainder of the terms and provisions herein shall be construed as if such invalid, illegal or unenforceable term or provision was not contained herein, but only to the extent that giving effect to such provision and the remainder of the terms and provisions hereof shall be in accordance with the intent of the parties as reflected in this Amendment. All references in the Original Agreement to the “Agreement” shall mean the Original Agreement as amended by this Amendment; provided, however, that all references to “date of this Agreement” in the Original Agreement shall continue to refer to the date of the Original Agreement.

9.This Amendment may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument. Delivery of an executed amendment by one party to the other may be made by facsimile transmission or electronic transmission (e.g., PDF).

[Remainder of Page Intentionally Blank]

-2-

If the foregoing correctly sets forth the understanding between the Company and the Agents, please so indicate in the space provided below for that purpose, whereupon this Amendment shall constitute a binding amendment to the Original Agreement between the Company and the Agents.

Very truly yours,

YORKVILLE IVES & CO., LLC

By:_/s/ Roger Briggs_______________________________

Name: Roger Briggs

Title: CEO

[Signature Page to Amendment No. 1 to Sales Agreement]

-3-

ROTH CAPITAL PARTNERS, LLC

By:_/s/_Seth Appel________________________________

Name: Seth Appel

Title: Head of ATM and Equity Alternatives Banking

[Signature Page to Amendment No. 1 to Sales Agreement]

-4-

ACCEPTED as of the date

first-above written:

ESS TECH, INC.

By:_/s/ Kate Suhadolnik__________________________

Name: Kate Suhadolnik

Title: Chief Financial Officer

[Signature Page to Amendment No. 1 to Sales Agreement]

-5-

SCHEDULE 1

FORM OF PLACEMENT NOTICE

From: ESS Tech, Inc.

To: [Yorkville Ives & Co., LLC] [Roth Capital Partners, LLC]

Attention: [•]

Subject: At the Market Issuance--Placement Notice

Date: [•]

Ladies and Gentlemen:

Pursuant to the terms and subject to the conditions contained in the Sales Agreement dated November 13, 2025 as amended by Amendment No. 1 on July 16, 2026, by and among ESS Tech, Inc., a Delaware corporation (the “Company”), Yorkville Ives & Co., LLC and Roth Capital Partners, LLC, the Company hereby requests that [identify Designated Agent] sell up to [____] of the Company’s Common Stock, par value $0.0001 per share, at a minimum market price of $ per share, during the time period beginning [month, day, time] and ending [month, day, time].

-6-

SCHEDULE 2

Notice Parties

The Company

Kelly Goodman [***]

Kate Suhadolnik [***]

Yorkville Ives

Owen Colwell [***]

Chris Pento [***]

With a copy to [***]

Roth

Lou Ellis [***]

Nazan Akdeniz [***]

Seth Appel [***]

With a copy to [***]

-7-

EXHIBIT 7(l)

Form of Representation Date Certificate

___________, 20___

This Representation Date Certificate (this “Certificate”) is executed and delivered in connection with Section 7(l) of the Sales Agreement (the “Agreement”), dated November 13, 2025, as amended by Amendment No. 1 on July 16, 2026, and entered into by and among ESS Tech, Inc. (the “Company”), Yorkville Ives & Co., LLC and Roth Capital Partners, LLC. All capitalized terms used but not defined herein shall have the meanings given to such terms in the Agreement.

The Company hereby certifies as follows:

1.As of the date of this Certificate (i) the Registration Statement, or as of its most recent effective date, did not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein not misleading and (ii) the Prospectus does not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading. The foregoing shall not apply to statements in, or omissions from, any such document made in reliance upon, and in conformity with, information furnished to the Company by an Agent specifically for use in the preparation thereof, it being understood and agreed that the only such information furnished by the Agents to the Company consists of “Agents Information” as defined in the Agreement.

2.Each of the representations and warranties of the Company contained in the Agreement were, when originally made, and are, as of the date of this Certificate (unless such representation or warranty specifies a different date or time, then as of such date or time), true and correct in all material respects.

3.Except as waived by the Agents in writing, each of the covenants required to be performed by the Company in the Agreement on or prior to this Representation Date has been duly, timely and fully performed in all material respects and each condition required to be complied with by the Company on or prior to this Representation Date as set forth in the Agreement has been duly, timely and fully complied with in all material respects.

4.Subsequent to the date of the most recent financial statements in the Prospectus, and except as described in the Prospectus, including Incorporated Documents, there has been no Material Adverse Effect.

5.No stop order suspending the effectiveness of the Registration Statement or of any part thereof has been issued, and no proceedings for that purpose have been instituted or are pending or, to the Company’s knowledge, threatened by any securities or other governmental authority (including, without limitation, the Commission).

[Signature Page Follows]

-8-

The undersigned has executed this Representation Date Certificate as of the date first written above.

ESS TECH, INC.

By:____________________________________

Name: Kate Suhadolnik

Title: Chief Financial Officer

-9-

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