ESS Tech, Inc.

Investor Relations Agreement

On December 29, 2025, we entered into an agreement with MZHCI, LLC to provide investor relations consulting services for an initial term of six months. We agreed to, among other things, issue MZHCI $199,999.92 worth of our restricted common stock, vesting in equal monthly increments over 12 months. The Company issued 9,363 shares to MZHCI on the 29th of each month from December 2025 through March 2026 and such securities were exempt from registration under Section 4(a)(2) of the Securities Act. The Company also agreed to provide performance bonuses if certain criteria are met, in the form of cash or restricted common stock (at the discretion of the Company).

VoltStorage Asset Purchase Agreement

On February 10, 2026, the Company entered into an asset purchase agreement with VoltStorage Gmbh (“VoltStorage”) pursuant to which the Company acquired certain fixed assets of VoltStorage in exchange for 100,000 shares of our common stock and $750,000. The shares were issued effective February 12th, 2026. The issuance did not involve any underwriters, any underwriting discounts or commissions, or any public offering. The issuances were made in a private transaction exempt from the registration requirements of the Securities Act pursuant to Section 4(a)(2) of the Securities Act, including Regulation S promulgated under the Securities Act.

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There were no sales of equity securities during the period covered by this report that were not registered under the Securities Act and/or were not previously reported in a Current Report on Form 8-K filed by the Company.