---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-21-300138"
form_type: "8-K"
ticker: "GWH"
cik: "0001819438"
company_name: "ESS Tech, Inc."
filed_at: "2021-10-15T23:59:59+00:00"
generated_at: "2026-06-28T20:37:35.651574+00:00"
event_type: "m_and_a"
sentiment: "neutral"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# ESS Tech completes de-SPAC merger with ACON S2; begins trading on NYSE as GWH

## Summary
- Merger closed Oct 8; ESS shares converted at 1.4711x; ~135M shares outstanding post-close.
- PIPE financing raised $250M from 25M newly issued shares at $10 each.
- New ESS common and warrants list on NYSE under GWH and GWH.W effective Oct 11.
- Lock-up period of 180 days; early release if 20-day VWAP exceeds $12 within any 30-day window after day 150.
- Up to 15.7M earnout shares contingently issuable based on milestones, representing ~11.6% dilution.

## SEC filing metadata
- accession: 0001193125-21-300138
- form_type: 8-K
- ticker: GWH
- cik: 0001819438
- company_name: ESS Tech, Inc.
- filed_at: 2021-10-15T23:59:59+00:00
- event_type: m_and_a
- sentiment: neutral
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 1.01, 2.01, 5.02, 3.02, 3.01, 3.03, 5.01, 5.03, 5.05, 5.06, 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1819438/000119312521300138/0001193125-21-300138-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1819438/000119312521300138/d231955d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-21-300138
- JSON: https://secwatch.observer/filing/0001193125-21-300138.json
- Plain text: https://secwatch.observer/filing/0001193125-21-300138.txt

## Key facts
- Executive change
  Alexi Wellman was appointed as director at ESS Tech, Inc..
  - Action: appointed
  - Role: director
  source text: the board of directors of New ESS (the “ Board ”) increased the size of the Board from eight to nine directors and appointed Alexi Wellman as an independent director, effective immediately.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1819438/000119312521300138/0001193125-21-300138-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.