UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

~~Pursuant~~PURSUANT toTO ~~Section~~SECTION 13 orOR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Date of ~~the~~Report ~~Securities~~(Date ~~Exchange~~of ~~Act~~earliest ofevent ~~1934~~reported): November 13, 2025

Date of report (Date of earliest event reported): October 14, 2025

ESS TECH, INC.

(Exact ~~Name~~name of ~~Registrant~~registrant as ~~Specified~~specified in ~~Charter~~charter)

Delaware

001-39525

98-1550150

(State or other jurisdictionof incorporation)

(CommissionFile Number)

(I.R.S. EmployerIdentification Number)

(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~~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

TradingSymbol(s)

Name of each exchangeon which registered

Common Stock, $0.0001 par value per share

GWH

The New York Stock Exchange

Warrants, each whole warrant exercisable for one share of common stock at an exercise price of $11.50

GWH.W

The New York Stock Exchange

Warrants, each fifteen warrants exercisable for one share of common stock at an exercise price of $172.50

GWH.W

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) 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 1.01 Entry into a Material Definitive Agreement.

On ~~October~~November 1413, 2025, ~~ESS~~in ~~Tech,~~connection ~~Inc.~~with (the ~~“Company”)~~launch ~~entered~~of ~~into~~ an ~~unsecured~~“at ~~promissory~~the ~~note~~market ~~with~~offering” ~~YA II PN~~program, ~~LTD.,~~ESS ~~an investment fund managed by Yorkville Advisors Global~~Tech, LInc.P. (the “~~Yorkville~~Company”) inentered ~~the~~into ~~aggregate~~a ~~principal~~Sales ~~amount~~Agreement ~~of up to $40 million~~ (the “~~Promissory~~Sales ~~Note~~Agreement”), inwith ~~two~~Yorkville ~~tranches~~Securities, ~~consisting~~LLC of(“Yorkville”), aBMO ~~first~~Capital ~~tranche~~Markets ofCorp., ~~$30~~Canaccord ~~million~~Genuity ~~and~~LLC, aNeedham ~~second~~& ~~tranche~~Company, ofLLC ~~$10~~and ~~million~~Stifel, inNicolaus ~~each~~& ~~case~~Company, ~~less~~Incorporated an(the ~~original~~“Agents”) ~~issue~~pursuant ~~discount~~to ofwhich 8%the ~~and~~Company ~~certain~~may ~~fees~~sell, ~~and~~from ~~expenses.~~time ~~Each~~to ~~tranche~~time, ~~may~~shares beof ~~drawn by~~ the Company’s ~~upon~~common ~~the~~stock, ~~satisfaction~~par ofvalue ~~certain~~$0.0001 ~~conditions,~~per ~~including,~~share ~~for~~ (the ~~second~~“Common ~~tranche~~Stock”), ~~upon~~during the ~~Company,~~term ~~among~~of ~~other~~the ~~things,~~Sales ~~entering~~Agreement ~~into~~through athe ~~sales~~Agents ~~agreement~~acting ~~with~~either ~~Yorkville~~as ~~Securities,~~agent ~~LLC,~~or anprincipal. ~~affiliate~~The ofCompany ~~Yorkville,~~has ~~related~~filed toa anprospectus ~~at-the-market~~supplement ~~offering~~with ~~program and~~ the ~~principal~~Securities ~~amount~~and ~~outstanding~~Exchange ~~under~~Commission (the ~~Promissory~~“SEC”) ~~Note~~relating ~~for~~to the ~~first~~offer ~~tranche~~and ~~being~~sale ~~equal~~of ~~to or less than~~ $2075 million. ~~The~~off ~~Promissory~~shares ~~Note accrues interest at a rate~~ of 3%Common ~~per~~Stock ~~annum,~~(the ~~amortizes~~“Shares”) ~~through~~pursuant ~~maturity~~to ~~and~~the ~~matures~~Sales ~~on October 14~~Agreement, ~~2026.~~which ~~The~~supplemented ~~Note~~the ~~contains~~base ~~customary~~prospectus ~~representations~~in ~~and warranties by~~ the Company’s ~~and~~previously ~~customary~~filed ~~events~~Registration ofStatement ~~default.~~on ~~The~~Form ~~proceeds~~S-3 of(File ~~the~~No. ~~Promissory~~333-268138), ~~Note~~which ~~may~~was bedeclared ~~used~~effective ~~for~~by ~~working~~the ~~capital~~SEC ~~and~~on ~~general~~November ~~corporate~~17, ~~purposes~~2022.

InThe ~~connection~~Company ~~with~~intends to use the ~~Promissory~~net ~~Note,~~proceeds from the ~~Company~~offering, ~~issued~~if toany, ~~Yorkville~~in acompliance ~~warrant~~with ~~exercisable~~the ~~for~~terms anof ~~aggregate~~that ~~number~~certain ofPromissory upNote, todated 1October 14,~~052~~ 2025,~~104~~ ~~shares~~between of the Company’s ~~common~~and ~~stock~~YA II PN, LTD., which is an affiliate of Yorkville (the “~~Warrant~~Promissory Note”)., ~~The~~which ~~Warrant~~generally ~~has~~requires anthat ~~exercise~~proceeds ~~price~~first ofbe ~~$9.98~~used ~~per~~to ~~share,~~satisfy ~~payable~~any ininstallment ~~cash~~payments ~~or,~~ under ~~certain~~the ~~circumstances,~~Promissory ~~pursuant~~Note todue ~~net~~within ~~exercise~~thirty days. ~~The~~After ~~Warrant~~any issuch ~~exercisable~~payments, ~~for~~80% ~~five~~of ~~years~~the remaining proceeds from this offering will be used to satisfy installment payments under the ~~date~~Promissory Note in direct order of ~~issuance~~maturity until the promissory note is repaid in full. ~~The~~In ~~issuance~~respect of the ~~Warrant~~remaining 20% of proceeds that the Company may receive while the Promissory Note is outstanding, and ~~the~~all ~~issuance~~net ofproceeds the ~~shares~~Company ~~issuable~~may ~~upon~~receive ~~exercise~~following the repayment of the ~~Warrant~~Promissory isNote, orthe isCompany ~~expected~~intends to ~~be,~~use ~~exempt~~such ~~from~~net ~~registration~~proceeds ~~pursuant~~for toworking ~~Section~~capital ~~4(a)(2)~~and orgeneral ~~Rule~~corporate ~~506~~purposes. ofCanaccord ~~Regulation~~Genuity DLLC ofis acting as the ~~Securities~~“qualified ~~Act.~~independent underwriter,” within the meaning of Financial Industry Regulatory Authority Rule 5121, in connection with the Offering.

The ~~foregoing~~Company ~~descriptions~~may, from time to time and subject to the terms of the ~~Promissory~~Sales ~~Note~~Agreement, ~~and~~sell the ~~Warrant~~Shares dothereunder, but is not ~~purport~~obligated to besell ~~complete~~any ~~and~~such ~~are~~Shares. ~~subject~~Subject to, the terms and ~~qualified~~conditions inof the Sales Agreement, the Agents will use their ~~entirety~~commercially byreasonably ~~reference~~efforts to sell, on the ~~full~~Company’s ~~text~~behalf, ofthe Shares offered by the ~~Promissory~~Company ~~Note~~under the Sales Agreement. Subject to the terms and conditions of the ~~Warrant~~Sales Agreement, ~~which~~the ~~are~~Agents ~~filed~~may assell ~~Exhibit~~Shares ~~10.1~~by ~~and~~any ~~Exhibit~~methods ~~4.1~~determined to ~~this~~be ~~Current~~an ~~Report~~“at onthe ~~Form~~market ~~8-K~~offering” as defined in Rule 415 promulgated under the Securities Act of 1933, ~~respectively.~~as amended.

~~Yorkville~~The isCompany ~~also~~has aagreed ~~party~~ to pay the ~~Company’s~~Agents ~~Standby~~a ~~Equity~~commission ~~Purchase~~equal ~~Agreement,~~to ~~and~~3.0% ~~Yorkville and/or one~~ of ~~its~~the ~~affiliates~~gross ~~may~~sales inprice ~~the~~of ~~future~~such ~~provide,~~Shares ~~certain~~pursuant ~~commercial~~to ~~banking,~~the ~~financial~~Sales ~~advisory,~~Agreement. ~~and~~The ~~investment~~Sales ~~banking~~Agreement ~~services~~contains incustomary ~~the~~representations, ~~ordinary~~warranties, ~~course~~and agreements of ~~business for~~ the Company, ~~including~~and ~~serving as sales agent under an at-~~the~~-market~~ ~~sales agreement~~Agents, ~~for~~indemnification ~~which~~rights ~~they have received~~ and ~~will~~obligations ~~receive~~of ~~customary~~the ~~fees~~parties and ~~commissions~~termination provisions.

~~Item~~The ~~2.03~~foregoing ~~Creation~~summary of the Sales Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Sales Agreement, a ~~Direct~~copy ~~Financial~~of ~~Obligation~~which oris anfiled ~~Obligation~~as ~~under~~Exhibit an1.1 ~~Off-Balance~~hereto ~~Sheet~~and ~~Arrangement~~incorporated herein by reference. The provisions of the Sales Agreement, including the representations and warranties contained therein, are not for the benefit of any party other than the parties to such Sales Agreement and are not intended as a ~~Registrant~~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.

~~The~~This ~~information~~Current ~~set~~Report ~~forth~~on Form 8-K shall not constitute an offer to sell or the solicitation of an offer to buy any Shares under the Sales Agreement, nor shall there be any sale of such Shares in ~~Item~~any 1jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction.01 ~~above~~Yorkville was a party to the Company’s Standby Equity Purchase Agreement, and an affiliate of Yorkville is ~~incorporated~~the bylender ~~reference~~under ~~into~~the ~~this~~Promissory ~~Item~~Note. 2Furthermore, the Agents 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.~~03.~~

Item 39.0201 ~~Unregistered~~Financial ~~Sales~~Statements ofand ~~Equity Securities~~Exhibits.

~~The information set forth in Item 1~~(d)Exhibits.~~01 above is incorporated by reference into this Item 3.02.~~

Item 9.01 Exhibits


Exhibit No.

1.1#						Sales Agreement, dated November 13, 2025, by and between ESS Tech, Inc. and Yorkville Securities, LLC, BMO Capital Markets Corp., Canaccord Genuity LLC, Needham & Company, LLC and Stifel, Nicolaus & Company, Incorporated

5.1						Opinion of Wilson Sonsini Goodrich & Rosati, Professional Corporation

23.1						Consent of Wilson Sonsini Goodrich & Rosati, Professional Corporation (included in Exhibit 5.1)

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

~~(d) Exhibits~~___________

Exhibit Number						Description of Document
4.1#						Form of Warrant
10.1#*						Promissory Note
99.1						Press release, dated October 14, 2025
104						Cover Page Interactive Data File - the cover page XBRL tags are embedded within the Inline XBRL document

# Certain of the exhibits and schedules to this exhibit have been omitted in accordance with Regulation S-K Item 601(a)(5). The registrant agrees to furnish a copy of all omitted exhibits and schedules to the SEC upon its request.

* Certain schedules and similar attachments to this Exhibit have been omitted in accordance with Item 601(a)(5) or (b)(2), as applicable of Regulation S-K. The registrants agree to furnish supplementally a copy of any omitted exhibit or schedule to the Securities and Exchange Commission upon its request.

# Certain confidential information contained in this exhibit has been omitted because it is both (i) not material; and (ii) the type that the registrants treat as private or confidential.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this ~~report~~Report to be signed on its behalf by the undersigned, hereunto duly authorized.

Dated: ~~October~~November 1413, 2025


ESS TECH, INC.

By:			/s/ Kate Suhadolnik
Name:			Kate Suhadolnik
Title:			Interim Chief Financial Officer

Filing Compare · ESS Tech, Inc.