Westlake Corporation (WLK) — insider trading
Materials · NYSE
Westlake Corporation (WLK) has 53 reported SEC Form 4 insider transactions in our data, including 6 open-market sales among the most recent 53 (latest 2026-08-31).
Recent Form 4 transactions
| Date | Insider | Role | Type | Shares | Price | Value | Filing |
|---|---|---|---|---|---|---|---|
| 2026-08-31 | Darby Tommy | Officer (VP and CAO) | Grant / award / vesting (derivative) | 1,791 | — | $0 | Form 4 |
| 2026-08-14 | Chao Catherine T. | Director | Grant / award / vesting (derivative) | 2,184 | — | $0 | Form 4 |
| 2026-08-14 | Chao David Tsung-Hung | Director | Grant / award / vesting (derivative) | 2,184 | — | $0 | Form 4 |
| 2026-08-14 | CREGG ROGER A | Director | Grant / award / vesting (derivative) | 2,184 | — | $0 | Form 4 |
| 2026-08-14 | Graff Michael J | Director | Grant / award / vesting (derivative) | 2,184 | — | $0 | Form 4 |
| 2026-08-14 | Lubel Kimberly S | Director | Grant / award / vesting (derivative) | 2,184 | — | $0 | Form 4 |
| 2026-08-14 | MCCOLLUM MARK A | Director | Grant / award / vesting (derivative) | 2,184 | — | $0 | Form 4 |
| 2026-08-14 | NORTHCUTT R BRUCE | Director | Grant / award / vesting (derivative) | 2,184 | — | $0 | Form 4 |
| 2026-08-14 | Patel Bhavesh V. | Director | Grant / award / vesting (derivative) | 2,184 | — | $0 | Form 4 |
| 2026-08-14 | Sabat Carolyn Chao | Director | Grant / award / vesting (derivative) | 2,184 | — | $0 | Form 4 |
| 2026-08-14 | Sheets Jeffrey Wayne | Director | Grant / award / vesting (derivative) | 2,184 | — | $0 | Form 4 |
| 2026-08-11 | Chao Albert | Director, Officer (Executive Chairman) | Option exercise / conversion (derivative) | 38,873 | — | $0 | Form 4 |
| 2026-08-11 | Chao Albert | Director, Officer (Executive Chairman) | Open-market sale | 31,384 | $80.42 | $2.52M | Form 4 |
| 2026-08-11 | Chao Albert | Director, Officer (Executive Chairman) | Open-market sale | 7,489 | $79.70 | $596.9K | Form 4 |
| 2026-08-11 | Chao Albert | Director, Officer (Executive Chairman) | Option exercise / conversion | 38,873 | $61.87 | $2.40M | Form 4 |
| 2026-08-08 | Chao Catherine T. | Director | Option exercise / conversion (derivative) | 2,168 | — | $0 | Form 4 |
| 2026-08-08 | Chao Catherine T. | Director | Option exercise / conversion | 2,168 | — | — | Form 4 |
| 2026-08-08 | Chao David Tsung-Hung | Director | Option exercise / conversion (derivative) | 2,168 | — | $0 | Form 4 |
| 2026-08-08 | Chao David Tsung-Hung | Director | Option exercise / conversion | 2,168 | — | — | Form 4 |
| 2026-08-08 | CREGG ROGER A | Director | Option exercise / conversion (derivative) | 2,168 | — | $0 | Form 4 |
| 2026-08-08 | CREGG ROGER A | Director | Option exercise / conversion | 2,168 | — | — | Form 4 |
| 2026-08-08 | Graff Michael J | Director | Option exercise / conversion (derivative) | 2,168 | — | $0 | Form 4 |
| 2026-08-08 | Graff Michael J | Director | Option exercise / conversion | 2,168 | — | — | Form 4 |
| 2026-08-08 | Lubel Kimberly S | Director | Option exercise / conversion (derivative) | 2,168 | — | $0 | Form 4 |
| 2026-08-08 | Lubel Kimberly S | Director | Option exercise / conversion | 2,168 | — | — | Form 4 |
| 2026-08-08 | MCCOLLUM MARK A | Director | Option exercise / conversion (derivative) | 2,168 | — | $0 | Form 4 |
| 2026-08-08 | MCCOLLUM MARK A | Director | Option exercise / conversion | 2,168 | — | — | Form 4 |
| 2026-08-08 | NORTHCUTT R BRUCE | Director | Option exercise / conversion (derivative) | 2,168 | — | $0 | Form 4 |
| 2026-08-08 | NORTHCUTT R BRUCE | Director | Option exercise / conversion | 2,168 | — | — | Form 4 |
| 2026-08-08 | Sabat Carolyn Chao | Director | Option exercise / conversion (derivative) | 2,168 | — | $0 | Form 4 |
| 2026-08-08 | Sabat Carolyn Chao | Director | Option exercise / conversion | 2,168 | — | — | Form 4 |
| 2026-08-08 | Sheets Jeffrey Wayne | Director | Option exercise / conversion (derivative) | 2,168 | — | $0 | Form 4 |
| 2026-08-08 | Sheets Jeffrey Wayne | Director | Option exercise / conversion | 2,168 | — | — | Form 4 |
| 2026-06-15 | Baksht Jonathan | Officer (SVP and CFO) | Grant / award / vesting (derivative) | 20,580 | — | $0 | Form 4 |
| 2026-05-13 | Bender Mark Steven | Officer (EVP & CFO) | Shares withheld for taxes / exercise cost | 5,284 | $97.34 | $514.3K | Form 4 |
| 2026-05-12 | Bender Mark Steven | Officer (EVP & CFO) | Option exercise / conversion (derivative) | 13,164 | — | $0 | Form 4 |
| 2026-05-12 | Bender Mark Steven | Officer (EVP & CFO) | Option exercise / conversion | 13,164 | — | $0 | Form 4 |
| 2026-04-02 | Powers Brian John | Officer (SVP, PEM Segment Head) | Grant / award / vesting (derivative) | 1,961 | — | $0 | Form 4 |
| 2026-03-27 | Buesinger Robert F. | Officer (EVP, PEM Segment Head) | Open-market sale | 4,000 | $115.25 | $461.0K | Form 4 |
| 2026-03-27 | Bender Mark Steven | Officer (EVP & CFO) | Open-market sale | 16,413 | $112.54 | $1.85M | Form 4 |
| 2026-02-27 | Bender Mark Steven | Officer (EVP & CFO) | Option exercise / conversion (derivative) | 6,494 | — | $0 | Form 4 |
| 2026-02-27 | Bender Mark Steven | Officer (EVP & CFO) | Option exercise / conversion (derivative) | 6,199 | — | $0 | Form 4 |
| 2026-02-27 | Bender Mark Steven | Officer (EVP & CFO) | Open-market sale | 421 | $101.52 | $42.7K | Form 4 |
| 2026-02-27 | Bender Mark Steven | Officer (EVP & CFO) | Open-market sale | 16,988 | $100.91 | $1.71M | Form 4 |
| 2026-02-27 | Bender Mark Steven | Officer (EVP & CFO) | Disposition to the issuer | 12,693 | $98.20 | $1.25M | Form 4 |
| 2026-02-27 | Bender Mark Steven | Officer (EVP & CFO) | Option exercise / conversion | 6,494 | $86.54 | $562.0K | Form 4 |
| 2026-02-27 | Bender Mark Steven | Officer (EVP & CFO) | Option exercise / conversion | 6,199 | $65.81 | $408.0K | Form 4 |
| 2026-02-20 | Patel Bhavesh V. | Director | Grant / award / vesting (derivative) | 1,852 | — | $0 | Form 4 |
| 2026-02-20 | Szwejbka Scott Thomas | Officer (SVP, HIP Segment Head) | Grant / award / vesting (derivative) | 3,983 | — | $0 | Form 4 |
| 2026-02-20 | Szwejbka Scott Thomas | Officer (SVP, HIP Segment Head) | Grant / award / vesting (derivative) | 14,595 | — | $0 | Form 4 |
| 2026-02-20 | Szwejbka Scott Thomas | Officer (SVP, HIP Segment Head) | Shares withheld for taxes / exercise cost | 91 | $94.10 | $8.6K | Form 4 |
| 2026-02-19 | Szwejbka Scott Thomas | Officer (SVP, HIP Segment Head) | Grant / award / vesting | 365 | — | $0 | Form 4 |
| 2022-02-16 | Bender Mark Steven | Officer (EVP & CFO) | Shares withheld for taxes / exercise cost | 1,171 | $104.96 | $122.9K | Form 4/A |
Ask the chat about WLK's insider activity →
Transaction types are the SEC Form 4 codes: open-market purchases (P) and sales (S) are the only rows that reflect open-market conviction. Awards/vesting (A), option exercises (M/X/C), shares withheld for taxes (F) and gifts (G) are compensation or mechanical, not buying or selling on the open market. Sales may be planned and non-discretionary (e.g. a Rule 10b5-1 plan); open-market buying is not a recommendation to buy. Informational only — not financial advice.
Source: SEC EDGAR Form 3/4/5. See the full company profile: Westlake Corporation (WLK).
Last updated 2026-08-31 (most recent filing date).
Informational only — NOT financial advice. Insider filings are sourced from SEC EDGAR and shown with their reported dates.