WLK · Westlake Corp

Weighted average price. These shares were sold in multiple transactions ranging from $79.02 to $80.01 inclusive. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.

The stock options are exercisable in three installments of 33%, 33% and 34% on February 17, 2018, 2019 and 2020, respectively.

Weighted average price. These shares were sold in multiple transactions ranging from $80.10 to $80.86 inclusive. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

On August 8, 2025 the reporting person was granted 2,168 restricted stock units vesting on the first anniversary of the grant date.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

On August 8, 2025 the reporting person was granted 2,168 restricted stock units vesting on the first anniversary of the grant date.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

On August 8, 2025 the reporting person was granted 2,168 restricted stock units vesting on the first anniversary of the grant date.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

On August 8, 2025 the reporting person was granted 2,168 restricted stock units vesting on the first anniversary of the grant date.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

On August 8, 2025 the reporting person was granted 2,168 restricted stock units vesting on the first anniversary of the grant date.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

On August 8, 2025 the reporting person was granted 2,168 restricted stock units vesting on the first anniversary of the grant date.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

On August 8, 2025 the reporting person was granted 2,168 restricted stock units vesting on the first anniversary of the grant date.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

On August 8, 2025 the reporting person was granted 2,168 restricted stock units vesting on the first anniversary of the grant date.

Restricted stock units convert into the Issuer's common stock on a one-for-one basis.

On August 8, 2025 the reporting person was granted 2,168 restricted stock units vesting on the first anniversary of the grant date.

Each restricted stock unit ("RSU") represents a contingent right to recieve one share of the Issuer's common stock.

All of the RSUs will vest on June 15, 2029.

Shares otherwise issuable were withheld to satisfy tax obligations arising out of the vesting of the reporting persons RSUs.

Restricted stock units ("RSUs") convert into the Issuer's common stock on a one-for-one basis.

On May 12, 2023, the reporting person was granted 13,164 RSUs vesting on the third anniversay of the grant date.

Restricted stock units ("RSUs") convert into the Issuer's common stock on a one-for-one basis.

Each restricted stock unit ("RSU") represents a contingent right to recieve one share of the Issuer's common stock.

All of the RSUs will vest on April 2, 2029.

Weighted average price. These shares were sold in multiple transactions at prices ranging from $112.33 to $112.99 inclusive. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.

The stock options are exercisable in three installments of 33%, 33% and 34% on February 19, 2022, 2023 and 2024, respectively.

Weighted average price. These shares were sold in multiple transactions at prices ranging from $100.38 to $101.36 inclusive. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.

The stock options are exercisable in three installments of 33%. 33% and 34% on February 14, 2021, 2022 and 2023, respectively.

The stock options are excercisable in three installments of 33%, 33% and 34% on February 20, 2027, 2028 and 2029, respectively.

Each restricted stock unit ("RSU") represents a contingent right to recieve one share of the Issuer's common stock.

All of the RSUs will vest on February 20, 2029.

Each restricted stock unit ("RSU") represents a contingent right to recieve one share of the Issuer's common stock.

All of the RSUs will vest on February 20, 2029.

The stock options are excercisable in three installments of 33%, 33% and 34% on February 20, 2027, 2028 and 2029, respectively.

Shares otherwise issuable were witheld to satisfy tax obligations arising out of vesting of the Reporting Person's PSUs.

Weighted average price. These shares were sold in multiple transactions at prices ranging from $94.10 to $94.38, inclusive. The Reporting Person undertakes to provide the Issuer, any security holder of the Issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.

Each restricted stock unit ("RSU") represents a contingent right to recieve one share of the Issuer's common stock.

All of the RSUs will vest on February 20, 2029.

Each restricted stock unit ("RSU") represents a contingent right to recieve one share of the Issuer's common stock.

All of the RSUs will vest on February 20, 2029.

Shares otherwise issuable were witheld to satisfy tax obligations arising out of vesting of the Reporting Person's PSUs.

Weighted average price. These shares were sold in multiple transactions at prices ranging from $94.10 to 94.38, inclusive. The Reporting Person undertakes to provide the Issuer, any security holder of the Issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.

Each restricted stock unit ("RSU") represents a contingent right to recieve one share of the Issuer's common stock.

All of the RSUs will vest on February 20, 2029.

The stock options are excercisable in three installments of 33%, 33% and 34% on February 20, 2027, 2028 and 2029, respectively.

Each restricted stock unit ("RSU") represents a contingent right to recieve one share of the Issuer's common stock.

All of the RSUs will vest on February 20, 2029.

The stock options are excercisable in three installments of 33%, 33% and 34% on February 20, 2027, 2028 and 2029, respectively.