The New York Stock Exchange (“NYSE”, the “Exchange”) announced today that the staff of NYSE Regulation has determined to commence proceedings to delist the common stock of ESS Tech, Inc. (the “Company”) — ticker symbol GWH — from the NYSE. NYSE Regulation reached its decision to commence proceedings to delist the Company’s common stock pursuant to Section 802.01B of the NYSE’s Listed Company Manual because the Company had fallen below the NYSE’s continued listing standard requiring listed companies to maintain an average global market capitalization over a consecutive 30 trading day period of at least $15,000,000. Trading in the Company’s common stock will be suspended immediately.

The Exchange previously announced on September 24, 2026 that the Company was no longer suitable for listing pursuant to Section 802.02 of the NYSE’s Listed Company Manual as the Company was unable to demonstrate that it had regained compliance with the applicable listing standard in Section 802.01B of the NYSE’s Listed Company Manual by the expiration of the maximum plan period.

The Company has a right to a review of these determinations by a Committee of the Board of Directors of the Exchange. The NYSE will apply to the Securities and Exchange Commission to delist the Company’s common stock upon completion of all applicable procedures, including any appeal by the Company of the NYSE Regulation staff’s decisions.