GWH · ESS Tech, Inc.

The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $1.0073 to $1.0299, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price.

The reported shares are represented by restricted stock units ("RSUs"), which vest on the earlier of (i) May 29, 2027 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs"), which vest on the earlier of (i) May 29, 2027 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs"), which vest on the earlier of (i) May 29, 2027 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs"), which vest on the earlier of (i) May 29, 2027 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs"), which vest on the earlier of (i) May 29, 2027 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

These shares were sold to cover tax withholding obligations in connection with the vesting of restricted stock units ("RSUs").

The price reported in sold Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.92 to $0.95, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

These shares were sold to cover tax withholding obligations in connection with the vesting of restricted stock units ("RSUs").

The price reported in sold Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.92 to $0.95, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

These shares were sold to cover tax withholding obligations in connection with the vesting of restricted stock units ("RSUs").

The price reported in sold Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.9024 to $0.971, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

These shares were sold to cover tax withholding obligations in connection with the vesting of restricted stock units ("RSUs").

The price reported in sold Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.9024 to $0.971, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

These shares were sold to cover tax withholding obligations in connection with the vesting of restricted stock units ("RSUs").

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

These shares were sold to cover tax withholding obligations in connection with the vesting of restricted stock units ("RSUs").

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs"), which vest as to 1/16th of the RSUs on May 20, 2026 and 1/16th of the RSUs shall vest quarterly thereafter, subject to the Reporting Person remaining a Service Provider to the Issuer through each such vest date.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs"), which vest as to 1/16th of the RSUs on May 20, 2026 and 1/16th of the RSUs shall vest quarterly thereafter, subject to the Reporting Person remaining a Service Provider to the Issuer through each such vest date.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

1/16th of the shares subject to the option shall vest on May 20, 2026 and 1/16th of the shares subject to the option shall vest quarterly thereafter, subject to the Reporting Person remaining a Service Provider to the issuer through each such vest date.

1/16th of the shares subject to the option shall vest on May 20, 2026 and 1/16th of the shares subject to the option shall vest quarterly thereafter, subject to the Reporting Person remaining a Service Provider to the issuer through each such vest date.

25 % of the shares subject to the option will vest on February 20, 2027 and 1/16th of the shares subject to the option shall vest quarterly thereafter, subject to the Reporting Person remains as Service Provider to the issuer through each such vest date.

The reported shares were withheld by the Issuer upon vesting of RSUs to satisfy tax withholding obligations.

portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares were withheld by the Issuer upon vesting of RSUs to satisfy tax withholding obligations.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his or her separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his or her separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his or her separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his or her separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his or her separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his or her separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his or her separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares were withheld by the Issuer upon vesting of RSUs to satisfy tax withholding obligations.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares were withheld by the Issuer upon vesting of RSUs to satisfy tax withholding obligations.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs"), which vest as to 1/4th of the RSUs on August 20, 2026 and 1/16th of the RSUs shall vest quarterly thereafter, subject to the Reporting Person remains as Service Provider to the issuer through each such vest date.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares were withheld by the Issuer upon vesting of restricted stock units, or RSUs, to satisfy tax withholding obligations.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares were withheld by the Issuer upon vesting of restricted stock units, or RSUs, to satisfy tax withholding obligations.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs"), which vest as to 1/16th of the RSUs on May 20, 2025 and 1/16th of the RSUs shall vest quarterly thereafter, subject to the Reporting Person remaining a Service Provider to the Issuer through each such vest date.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by RSUs, which vest as to 1/16th of the RSUs on May 20, 2025 and 1/16th of the RSUs shall vest quarterly thereafter, subject to the Reporting Person remaining a Service Provider to the Issuer through each such vest date.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares were withheld by the Issuer upon vesting of RSUs to satisfy tax withholding obligations.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares were withheld by the Issuer upon vesting of restricted stock units, or RSUs, to satisfy tax withholding obligations.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest in 16 equal quarterly installments beginning on February 20, 2025.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares were withheld by the Issuer upon vesting of restricted stock units, or RSUs, to satisfy tax withholding obligations.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

A portion of these securities are Restricted Stock Units ("RSUs"). Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

On August 23, 2024, the Issuer completed a one-for-fifteen reverse stock split of its common stock. All of the share numbers have been adjusted to reflect this reverse stock split.

The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSU's.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

On August 23, 2024, the Issuer completed a one-for-fifteen reverse stock split of its common stock. All of the share numbers have been adjusted to reflect this reverse stock split.

On August 23, 2024, the issuer completed a one-for-fifteen reverse stock split of its common stock. All of the share numbers have been adjusted to reflect the reverse stock split.

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

On August 23, 2024 the issuer completed a one-for-fifteen reverse stock split of its common stock. All of the share numbers have been adjusted to reflect this reverse stock split.

The reported shares were withheld by the Issuer upon vesting of restricted stock units, or RSUs, to satisfy tax withholding obligations.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares were withheld by the Issuer upon vesting of restricted stock units, or RSUs, to satisfy tax withholding obligations.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by RSUs which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.

The reported shares are represented by restricted stock units ("RSUs") which vest on the earlier of (i) May 17, 2025 or (ii) the day prior to the next annual meeting of stockholders. The Reporting Person has elected to defer the settlement of these RSUs to a date within 30 days of the earlier of (i) his separation of service from the Issuer within the meaning of Section 409A of the Internal Revenue Code (Section 409A) or (ii) the date on which a change of control (as defined in the Issuer's plan) occurs, provided that such transaction qualifies as a change of control within the meaning of Section 409A.

A portion of these securities are RSUs. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock.