Levy Sarah Kirshbaum

SEC source: 0001786657-26-000004 · wk-form4_1781641024.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: CLASS A COMMON STOCK · 17,419 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_price: Each RSU represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs have fully vested on June 12, 2026, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F2 · derivative.exercise_date: Each RSU represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs have fully vested on June 12, 2026, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F2 · derivative.expiration_date: Each RSU represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs have fully vested on June 12, 2026, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0001786657-26-000004 · wk-form4_1781641024.xml · nonDerivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 40,892

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Restricted stock units ("RSUs") converted into Class A Common Stock on a one-for-one basis.

SEC source: 0001786657-26-000002 · wk-form4_1780698850.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 21,445

Underlying: CLASS A COMMON STOCK · 21,445 shares

Expires 2036-06-03

F2 · derivative.exercise_date: The option will vest and become exercisable on June 3, 2027, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0001786657-26-000002 · wk-form4_1780698850.xml · derivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 14,368

Underlying: CLASS A COMMON STOCK · 14,368 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 3, 2027, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 3, 2027, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 3, 2027, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0001704711-25-000096 · wk-form4_1749848097.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 26,000

Underlying: CLASS A COMMON STOCK · 26,000 shares

Expires 2035-06-12

F2 · derivative.exercise_date: The option will vest and become exercisable on June 12, 2026, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0001704711-25-000096 · wk-form4_1749848097.xml · derivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17,419

Underlying: CLASS A COMMON STOCK · 17,419 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 12, 2026, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 12, 2026, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 12, 2026, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0001704711-25-000085 · wk-form4_1749241081.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: CLASS A COMMON STOCK · 10,204 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 4, 2025, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F2 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 4, 2025, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F2 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 4, 2025, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0001704711-25-000085 · wk-form4_1749241081.xml · nonDerivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,473

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Restricted stock units ("RSUs") converted into Class A Common Stock on a one-for-one basis.

SEC source: 0001704711-24-000110 · wk-form4_1718397629.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: CLASS A COMMON STOCK · 4,688 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment.

F3 · derivative.exercise_date: On June 13, 2023, the Reporting Person was granted 4,688 RSUs, vesting in full on the first anniversary of the grant date, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F3 · derivative.expiration_date: On June 13, 2023, the Reporting Person was granted 4,688 RSUs, vesting in full on the first anniversary of the grant date, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0001704711-24-000110 · wk-form4_1718397629.xml · nonDerivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,269

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Restricted stock units ("RSUs") converted into Class A Common Stock on a one-for-one basis.

SEC source: 0001704711-24-000096 · wk-form4_1717711638.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 25,500

Underlying: CLASS A COMMON STOCK · 25,500 shares

Expires 2034-06-04

F2 · derivative.exercise_date: The option will vest and become exercisable on June 4, 2025, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0001704711-24-000096 · wk-form4_1717711638.xml · derivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,204

Underlying: CLASS A COMMON STOCK · 10,204 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 4, 2025, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 4, 2025, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 4, 2025, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000950170-23-028382 · ownership.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,700

Underlying: Class A Common Stock · 11,700 shares

Expires 2033-06-13

F2 · derivative.exercise_date: The option will vest and become exercisable on June 13, 2024, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000950170-23-028382 · ownership.xml · derivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,688

Underlying: Class A Common Stock · 4,688 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 13, 2024, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 13, 2024, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 13, 2024, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000950170-23-024520 · ownership.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 2,080 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Restricted stock units converted into Class A Common Stock on a one-for-one basis.

F2 · derivative.exercise_date: On May 24, 2022, the Reporting Person was granted 2,080 restricted stock units, vesting in full on the first anniversary of the grant date, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F2 · derivative.expiration_date: On May 24, 2022, the Reporting Person was granted 2,080 restricted stock units, vesting in full on the first anniversary of the grant date, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000950170-23-024520 · ownership.xml · nonDerivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,581

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Restricted stock units converted into Class A Common Stock on a one-for-one basis.

SEC source: 0000899243-22-021364 · doc4.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 1,593 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vested on June 4, 2022.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vested on June 4, 2022.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vested on June 4, 2022.

SEC source: 0000899243-22-021364 · doc4.xml · nonDerivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,501

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000899243-22-019760 · doc4.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,200

Underlying: Class A Common Stock · 5,200 shares

Expires 2032-05-24

F2 · derivative.exercise_date: The option will vest and become exercisable on May 24, 2023, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000899243-22-019760 · doc4.xml · derivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,080

Underlying: Class A Common Stock · 2,080 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on May 24, 2023, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on May 24, 2023, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on May 24, 2023, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000899243-21-040095 · doc4.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 50,000 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

F1 · kind: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

F1 · price: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

F1 · derivative.exercise_date: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

F1 · derivative.expiration_date: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

F1 · derivative.underlying_shares: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

F1 · balance_after: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

F1 · ownership.direct: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

SEC source: 0000899243-21-040095 · doc4.xml · nonDerivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 50,000

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

F1 · price: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

F1 · ownership.direct: Pursuant to the Agreement and Plan of Merger, dated May 6, 2021, by and among ACON S2 Acquisition Corp., a Cayman Islands exempted company (the "Company"), SCharge Merger Sub, Inc., a Delaware corporation, and ESS Tech, Inc., a Delaware corporation ("ESS"), the parties effected a business combination transaction ("Business Combination"), on October 8, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "ESS Tech, Inc." ("New ESS"). In connection with the consummation of the Business Combination, 50,000 of Sarah Kirshbaum Levy's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company converted into shares of common stock, par value $0.0001, of New ESS simultaneously with the closing of the Business Combination.

SEC source: 0000899243-21-022553 · doc4.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,983

Underlying: Class A Common Stock · 3,983 shares

Expires 2031-06-04

F2 · derivative.exercise_date: The option will vest and become exercisable on June 4, 2022, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000899243-21-022553 · doc4.xml · derivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,593

Underlying: Class A Common Stock · 1,593 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 4, 2022, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 4, 2022, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on June 4, 2022, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000899243-21-021232 · doc4.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 3,616 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vested on May 27, 2021.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vested on May 27, 2021.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vested on May 27, 2021.

SEC source: 0000899243-21-021232 · doc4.xml · nonDerivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,908

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000899243-20-024413 · doc4.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 1,292 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vested on September 3, 2020.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vested on September 3, 2020.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vested on September 3, 2020.

SEC source: 0000899243-20-024413 · doc4.xml · nonDerivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,292

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000899243-20-014592 · doc4.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,900

Underlying: Class A Common Stock · 5,900 shares

Expires 2030-05-27

F2 · derivative.exercise_date: The option will vest and become exercisable on May 27, 2021, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000899243-20-014592 · doc4.xml · derivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,616

Underlying: Class A Common Stock · 3,616 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on May 27, 2021, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on May 27, 2021, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest on May 27, 2021, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000899243-19-022879 · doc4.xml · derivative · entry 2

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,916

Underlying: Class A Common Stock · 3,916 shares

Expires 2029-09-03

F2 · derivative.exercise_date: The option will vest in full and become exercisable on September 3, 2020, subject to the Reporting Person's continued service with the Issuer through the vesting date.

SEC source: 0000899243-19-022879 · doc4.xml · derivative · entry 1

Levy Sarah Kirshbaum · CIK 0001786657 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,292

Underlying: Class A Common Stock · 1,292 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest in full on September 3, 2020, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.exercise_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest in full on September 3, 2020, subject to the Reporting Person's continued service with the Issuer through the vesting date.

F1 · derivative.expiration_date: Each restricted stock unit ("RSU") represents a contingent right to receive one share of Class A Common Stock or, at the election of the Issuer, an equivalent cash payment. The RSUs vest in full on September 3, 2020, subject to the Reporting Person's continued service with the Issuer through the vesting date.