ESS Tech, Inc. — Director's Dealing 2021

Oct 19, 2021

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: ESS Tech, Inc. (GWH)
CIK: 0001819438
Period of Report: 2021-10-08

Reporting Person: NIGGLI MICHAEL R (Director)

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	414414	Direct
Common Stock	196260	Indirect
Common Stock	490480	Indirect
Common Stock	73555	Indirect
Common Stock	73555	Indirect
Common Stock	73555	Indirect
Common Stock	73555	Indirect

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Stock Option (right to buy)	$0.3061	2028-10-18	Common Stock (177785)		Direct
Restricted Stock Units	$	2026-04-08	Common Stock (30053)		Direct

Footnotes

F1: Pursuant to an "earnout" provision of the Agreement and Plan of Merger, dated as of May 6, 2021 (the "Merger Agreement"), by and among ACON S2 Acquisition Corp, SCharge Merger Sub, Inc., and ESS Tech, Inc., the reporting person is entitled to receive additional shares of common stock, for no additional consideration, if the volume weighted average price of the common stock over twenty trading days within any thirty trading day period exceeds certain thresholds (the "Earnout Rights"). Of these Earnout Rights, one half will be issued if the volume weighted average price of the common stock over twenty trading days within any thirty trading day period is greater than or equal to $12.50, and one half will be issued if the volume weighted average price of the common stock over twenty trading days within any thirty trading day period is greater than or equal to $15.00.

F2: The shares are held of record by the Michael R. Niggli Family Trust for which the reporting person serves as trustee.

F3: The shares are held of record by the Linda Naviaux Niggli Trust for which the reporting person's spouse serves as trustee.

F4: The shares are held of record by the Chloe D. Niggli Gift Trust for which the reporting person serves as trustee.

F5: The shares are held of record by the Ian M. Niggli 2021 Gift Trust for which the reporting person serves as trustee.

F6: The shares are held of record by the Lorelei A. Niggli 2021 Gift Trust for which the reporting person serves as trustee.

F7: The shares are held of record by the Michael R. Niggli Jr. 2021 Gift Trust for which the reporting person serves as trustee.

F8: The shares subject to the option vest in 48 equal monthly installments beginning on August 20, 2018.

F9: Each restricted stock unit, or RSU, represents a contingent right to receive one share of common stock. The RSUs vest if the common stock exceeds the same thresholds as the Earnout Rights described in footnote (1).