{"schema_version":"secwatch.filing_event.v1","accession":"0001819438-26-000049","form_type":"8-K","ticker":"GWH","cik":"0001819438","company_name":"ESS Tech, Inc.","filed_at":"2026-06-18T21:27:54+00:00","discovered_at":"2026-06-18T21:30:00.309225+00:00","generated_at":"2026-06-18T21:31:12.504184+00:00","sec_items":["5.02"],"event_type":"leadership","sentiment":"neutral","materiality_score":0.2,"calibrated_materiality_score":0.2,"confidence":"high","headline":"Board member Rich Hossfeld resigns; Raffi Garabedian takes audit committee seat.","bullets":["Rich Hossfeld resigned from ESS Tech board and Audit Committee effective June 12, 2026.","Raffi Garabedian appointed to the Audit Committee effective June 12, 2026.","Resignation not due to any disagreement with company on operations, policies, or practices.","Company thanked Hossfeld for years of service and contributions."],"urls":{"canonical":"https://secwatch.observer/filing/0001819438-26-000049","json":"https://secwatch.observer/filing/0001819438-26-000049.json","markdown":"https://secwatch.observer/filing/0001819438-26-000049.md","text":"https://secwatch.observer/filing/0001819438-26-000049.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1819438/000181943826000049/0001819438-26-000049-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1819438/000181943826000049/wk-20260612.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-06-18T21:31:12.504184+00:00"},"review":{"review_status":"machine_generated","human_reviewed":false,"corrected":false,"correction_note":null,"correction_timestamp":null,"superseded_by":null,"related_filings":[]},"source_grounded_claims":[{"claim_id":"236098c2d4","claim":"Rich Hossfeld resigned as Director at ESS Tech, Inc..","evidence_excerpt":"On June 12, 2026, Rich Hossfeld notified ESS Tech, Inc. (the “Company”) that he is resigning from the board of directors (the “Board”) of the Company and Audit Committee of the Board (the “Audit Committee”), effective as of June 12, 2026.","evidence_source":"SEC 8-K Item 5.02","evidence_url":"https://www.sec.gov/Archives/edgar/data/1819438/000181943826000049/0001819438-26-000049-index.htm","confidence":0.95,"family_label":"Executive change","details":[{"label":"Action","value":"resigned"},{"label":"Role","value":"Director"}],"fact_type":"executive_change"},{"claim_id":"456436fa8f","claim":"Raffi Garabedian was appointed as Audit Committee Member at ESS Tech, Inc..","evidence_excerpt":"Raffi Garabedian will replace Mr. Hossfeld on the Audit Committee, effective as of June 12, 2026.","evidence_source":"SEC 8-K Item 5.02","evidence_url":"https://www.sec.gov/Archives/edgar/data/1819438/000181943826000049/0001819438-26-000049-index.htm","confidence":0.9,"family_label":"Executive change","details":[{"label":"Action","value":"appointed"},{"label":"Role","value":"Audit Committee Member"}],"fact_type":"executive_change"}],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}