Russell Kline

SEC source: 0001654954-25-014121 · section16.xml · nonDerivative · entry 1

Russell Kline · CIK 0002049257 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 668,642

SEC source: 0001654954-25-011766 · section16.xml · derivative · entry 1

Russell Kline · CIK 0002049257 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 808,642

Underlying: Common Stock · 500,000 shares

Expires not disclosed

F1 · security: . Represents stock options granted to the Reporting Person as a special retention incentive award in connection with his continued service as Chief Financial Officer of 374Water Inc. (the "Company"). 50% of the stock options vest and become exercisable on the first anniversary of the grant date and the remaining 50% of the stock options vest and become exercisable on the second anniversary of the grant date, subject to the Reporting Person's continuous service through each vesting date. In the event of an involuntary termination of the Reporting Person without cause, all remaining unvested stock options will vest and become exercisable immediately. Upon vesting, each stock option gives the Reporting Person the right to purchase one share of the Company's Common Stock at the exercise price. The stock options expire on the date which is ten years from the grant date, unless earlier terminated in accordance with the stock option grant agreement.

F1 · shares: . Represents stock options granted to the Reporting Person as a special retention incentive award in connection with his continued service as Chief Financial Officer of 374Water Inc. (the "Company"). 50% of the stock options vest and become exercisable on the first anniversary of the grant date and the remaining 50% of the stock options vest and become exercisable on the second anniversary of the grant date, subject to the Reporting Person's continuous service through each vesting date. In the event of an involuntary termination of the Reporting Person without cause, all remaining unvested stock options will vest and become exercisable immediately. Upon vesting, each stock option gives the Reporting Person the right to purchase one share of the Company's Common Stock at the exercise price. The stock options expire on the date which is ten years from the grant date, unless earlier terminated in accordance with the stock option grant agreement.

F1 · derivative.exercise_date: . Represents stock options granted to the Reporting Person as a special retention incentive award in connection with his continued service as Chief Financial Officer of 374Water Inc. (the "Company"). 50% of the stock options vest and become exercisable on the first anniversary of the grant date and the remaining 50% of the stock options vest and become exercisable on the second anniversary of the grant date, subject to the Reporting Person's continuous service through each vesting date. In the event of an involuntary termination of the Reporting Person without cause, all remaining unvested stock options will vest and become exercisable immediately. Upon vesting, each stock option gives the Reporting Person the right to purchase one share of the Company's Common Stock at the exercise price. The stock options expire on the date which is ten years from the grant date, unless earlier terminated in accordance with the stock option grant agreement.

F1 · derivative.expiration_date: . Represents stock options granted to the Reporting Person as a special retention incentive award in connection with his continued service as Chief Financial Officer of 374Water Inc. (the "Company"). 50% of the stock options vest and become exercisable on the first anniversary of the grant date and the remaining 50% of the stock options vest and become exercisable on the second anniversary of the grant date, subject to the Reporting Person's continuous service through each vesting date. In the event of an involuntary termination of the Reporting Person without cause, all remaining unvested stock options will vest and become exercisable immediately. Upon vesting, each stock option gives the Reporting Person the right to purchase one share of the Company's Common Stock at the exercise price. The stock options expire on the date which is ten years from the grant date, unless earlier terminated in accordance with the stock option grant agreement.

F1 · derivative.underlying_shares: . Represents stock options granted to the Reporting Person as a special retention incentive award in connection with his continued service as Chief Financial Officer of 374Water Inc. (the "Company"). 50% of the stock options vest and become exercisable on the first anniversary of the grant date and the remaining 50% of the stock options vest and become exercisable on the second anniversary of the grant date, subject to the Reporting Person's continuous service through each vesting date. In the event of an involuntary termination of the Reporting Person without cause, all remaining unvested stock options will vest and become exercisable immediately. Upon vesting, each stock option gives the Reporting Person the right to purchase one share of the Company's Common Stock at the exercise price. The stock options expire on the date which is ten years from the grant date, unless earlier terminated in accordance with the stock option grant agreement.

SEC source: 0001654954-25-010328 · section16.xml · nonDerivative · entry 1

Russell Kline · CIK 0002049257 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 648,642

F1 · shares: The restricted stock unit vests in equal monthly installments over 36 months, on the last day of each month, beginning on March 31, 2025, subject to the Reporting Person's continuous service through each vesting date.

SEC source: 0001654954-25-009981 · section16.xml · nonDerivative · entry 2

Russell Kline · CIK 0002049257 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 398,642

F2 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $0.2450 to $0.2519, inclusive. The reporting person undertakes to provide to 374Water Inc., any security holder of 374Water Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in footnote (2) to this Form 4.

SEC source: 0001654954-25-009981 · section16.xml · nonDerivative · entry 1

Russell Kline · CIK 0002049257 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 383,642

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $0.2444 to $0.2493, inclusive. The reporting person undertakes to provide to 374Water Inc., any security holder of 374Water Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in footnote (1) to this Form 4.

SEC source: 0001654954-25-009916 · section16.xml · nonDerivative · entry 1

Russell Kline · CIK 0002049257 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 368,642

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $0.2368 to $0.2416, inclusive. The reporting person undertakes to provide to 374Water Inc., any security holder of 374Water Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in footnote (1) to this Form 4.

SEC source: 0001654954-25-000547 · section16.xml · derivative · entry 2

Russell Kline · CIK 0002049257 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 308,642

Underlying: Common Stock · 308,642 shares

Expires 2025-01-14

F1 · shares: Vesting commencement date is December 16, 2024. 25% of the shares vest and become exercisable on the first annual anniversary of the vesting commencement date and the balance vest and become exercisable equally on the last day of every month thereafter over the following 36 months, subject to the Reporting Person's continuous service through each vesting date.

F1 · derivative.exercise_date: Vesting commencement date is December 16, 2024. 25% of the shares vest and become exercisable on the first annual anniversary of the vesting commencement date and the balance vest and become exercisable equally on the last day of every month thereafter over the following 36 months, subject to the Reporting Person's continuous service through each vesting date.

SEC source: 0001654954-25-000547 · section16.xml · nonDerivative · entry 1

Russell Kline · CIK 0002049257 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 348,642

F1 · shares: Vesting commencement date is December 16, 2024. 25% of the shares vest and become exercisable on the first annual anniversary of the vesting commencement date and the balance vest and become exercisable equally on the last day of every month thereafter over the following 36 months, subject to the Reporting Person's continuous service through each vesting date.