144 0001330417 XXXXXXXX LIVE 0001262823 WESTLAKE CORPORATION 001-32260 2801 Post Oak Boulevard, Suite 600 Houston TX 77056 (713) 960-9111 MARK BENDER Officer Common Morgan Stanley Smith Barney LLC Executive Financial Services

1 New York Plaza 8th Floor New York NY 10004

16413 1847033.67 127910338 03/27/2026 NYSE Common 02/14/2021 Restricted Stock Issuer N 1076 02/14/2021 Not Applicable Common 02/18/2022 Performance Shares Issuer N 4777 02/18/2022 Not Applicable Common 02/19/2024 Restricted Stock Issuer N 3139 02/19/2024 Not Applicable Common 02/17/2020 Restricted Stock Issuer N 3918 02/17/2020 Not Applicable Common 02/18/2025 Restricted Stock Issuer N 3503 02/18/2025 Not Applicable N MARK BENDER

2801 Post Oak Boulevard, Suite 600 Houston TX 77056

Common 02/27/2026 30102 3003393.25 MARK BENDER

2801 Post Oak Boulevard, Suite 600 Houston TX 77056

COMMON 02/20/2026 445 41874.14 MARK BENDER

2801 Post Oak Boulevard, Suite 600 Houston TX 77056

COMMON 02/18/2026 1209 119630.55 03/27/2026 /s/ Mark Steven Bender