<SEC-DOCUMENT>0001628280-25-034768-index.html : 20250711 <SEC-HEADER>0001628280-25-034768.hdr.sgml : 20250711 <ACCEPTANCE-DATETIME>20250711092342 ACCESSION NUMBER: 0001628280-25-034768 CONFORMED SUBMISSION TYPE: 424B2 PUBLIC DOCUMENT COUNT: 3 FILED AS OF DATE: 20250711 DATE AS OF CHANGE: 20250711 FILER: COMPANY DATA: COMPANY CONFORMED NAME: ESS Tech, Inc. CENTRAL INDEX KEY: 0001819438 STANDARD INDUSTRIAL CLASSIFICATION: MISCELLANEOUS ELECTRICAL MACHINERY, EQUIPMENT & SUPPLIES [3690] ORGANIZATION NAME: 04 Manufacturing EIN: 981550150 STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: 424B2 SEC ACT: 1933 Act SEC FILE NUMBER: 333-268138 FILM NUMBER: 251117671 BUSINESS ADDRESS: STREET 1: 26440 SW PARKWAY AVE. STREET 2: BLDG. 83 CITY: WILSONVILLE STATE: OR ZIP: 97070 BUSINESS PHONE: (855) 423-9920 MAIL ADDRESS: STREET 1: 26440 SW PARKWAY AVE. STREET 2: BLDG. 83 CITY: WILSONVILLE STATE: OR ZIP: 97070 FORMER COMPANY: FORMER CONFORMED NAME: ACON S2 Acquisition Corp. DATE OF NAME CHANGE: 20200728 </SEC-HEADER> <DOCUMENT> <TYPE>424B2 <SEQUENCE>1 <FILENAME>prospectussupplementjuly20.htm <DESCRIPTION>424B2 <TEXT> Document 1 - file: prospectussupplementjuly20.htm
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>2 <FILENAME>backcover1aa.jpg <TEXT> Document 2 - file: backcover1aa.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>3 <FILENAME>esslogo.jpg <TEXT> Document 3 - file: esslogo.jpg
</DOCUMENT> </SEC-DOCUMENT>