Welcome to our dedicated page for WESTLAKE CORPORATION SEC filings (Ticker: WLK), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
The Westlake Corporation (NYSE: WLK) SEC filings page on Stock Titan provides direct access to the company’s regulatory disclosures, including current reports on Form 8-K and other key documents filed with the U.S. Securities and Exchange Commission. Westlake is a Houston-headquartered global manufacturer and supplier of materials and products serving housing and construction, packaging, healthcare, automotive and consumer goods, and its filings offer detailed insight into these activities.
Recent Form 8-K filings describe a range of material events. These include the announcement and completion of Westlake’s acquisition of the global compounding solutions businesses of the ACI/Perplastic Group, which expands Westlake Global Compounds’ presence in specialty materials for the wire and cable sectors and extends its manufacturing footprint into Portugal, Romania and Tunisia. Other 8-Ks outline an underwriting agreement and the issuance of senior notes due 2035 and 2055, the commencement and pricing of a cash tender offer for 3.600% senior notes due 2026, and the results of that tender offer.
Filings also cover operational decisions, such as an 8-K reporting a plan to cease operation of certain North American chlorovinyl production facilities and a styrene plant at Lake Charles, Louisiana, while continuing to supply PVC, VCM and chlor-alkali products from seven other North American chlorovinyl facilities. Additional 8-Ks furnish quarterly earnings press releases, investor presentations and dividend announcements.
On Stock Titan, these SEC filings are paired with AI-powered summaries that explain the core points of each document in plain language. Users can quickly understand the significance of a tender offer, a new debt issuance, an acquisition closing or a capacity rationalization without reading every page. The filings page updates as new documents are posted to EDGAR, helping investors follow Westlake’s material events, financing activities and strategic moves through its official disclosures.
Westlake Corp Senior Chairman James Chao reported equity award activity and related tax withholding. On February 17, 2026, 10,382 restricted stock units converted on a one-for-one basis into 10,382 shares of common stock at a stated price of $0.00 per share, reflecting vesting of RSUs granted on February 17, 2023.
On February 18, 2026, 2,664 common shares were disposed of at $98.95 per share to satisfy tax obligations arising from the RSU vesting, rather than through an open-market sale. After these transactions, Chao directly held 47,459 shares of Westlake common stock.
Westlake Corp director John Tsung-chen Chao reported equity compensation activity involving restricted stock units and common stock. On February 17, 2026, 570 restricted stock units converted into an equal number of Westlake common shares following a grant made on February 17, 2023 that vested on the third anniversary.
On February 18, 2026, 242 of the shares otherwise issuable were withheld at a price of $98.95 per share to cover tax obligations arising from the RSU vesting. After these transactions and an ownership reconciliation that added 400 previously unreported shares, Chao directly holds 7,766 common shares of Westlake Corp.
WESTLAKE CORP Executive Chairman Albert Chao reported RSU vesting and related share withholding. On February 17, he exercised 16,555 restricted stock units, which convert into common stock on a one-for-one basis, resulting in 16,555 common shares acquired at a stated price of $0.00 per share.
On February 18, 5,089 common shares were disposed of at $98.95 per share to satisfy tax obligations arising from the RSU vesting, rather than through an open-market sale. After these transactions, he directly owned 639,188 shares of Westlake common stock.
Westlake Corp executive Robert F. Buesinger reported equity award activity and related tax withholding. On February 17, 2026, 3,478 restricted stock units were exercised into the same number of common shares at $0.00 per share, reflecting the vesting of RSUs granted on February 17, 2023. Following this conversion, his direct common stock holdings rose to 38,410 shares. On February 18, 2026, 903 common shares valued at $98.95 per share were disposed of to cover tax obligations from the RSU vesting, reducing his direct holdings to 37,507 shares.
Westlake Corp executive Mark Steven Bender reported equity compensation activity involving restricted stock units (RSUs) and common stock. On February 17, 4,751 RSUs converted into an equal number of Westlake common shares at a stated price of $0.0000 per share. Following this derivative exercise, his direct common stock holdings increased to 61,719 shares.
On February 18, 1,209 common shares were disposed of through a tax-withholding transaction at $98.95 per share to satisfy tax obligations arising from the RSU vesting, as described in the footnotes. After this withholding, Bender directly holds 60,510 shares of Westlake common stock.
Westlake Corporation has completed its previously announced acquisition of the global compounding solutions businesses of the ACI/Perplastic Group. The company disclosed the closing through a press release dated January 5, 2026, which is furnished as Exhibit 99.1 under a Regulation FD disclosure. This step confirms that the transaction has moved from agreement to completion.
The furnished press release is not treated as filed for liability purposes under the Exchange Act and is not automatically incorporated into other securities law filings unless specifically identified. No purchase price or financial terms are included in this disclosure.
Westlake Corp’s executive chairman and director reported an option exercise and share sales in the company’s common stock. On 12/22/2025, he exercised an employee stock option to acquire 81,673 shares of common stock at an exercise price of $44.42 per share, increasing his direct holdings.
That same day, he sold shares in several open-market transactions, including 9,711 shares at a weighted average price of $72.818, 30,604 shares at a weighted average price of $73.796, and 521 shares at a weighted average price of $74.443. A portion of the sale proceeds was used to pay the option strike price and related taxes. After these transactions, he directly owned 627,722 shares of Westlake Corp common stock, and the reported option position was reduced to zero.
A holder of 40,836 shares of common stock of WLK has filed a notice of proposed sale under Rule 144. The shares are expected to be sold through Morgan Stanley Smith Barney LLC on the NYSE, with an indicated aggregate market value of $3,004,365.77 and an approximate sale date of 12/22/2025. The filing states that these shares were acquired on 12/22/2025 through a stock option exercise for cash. The issuer reports 128,273,220 shares of this class outstanding, which serves as a baseline for the company’s equity.
Westlake Corporation has approved plans to shut several North American chlorovinyl and styrene production facilities, triggering significant restructuring costs. The closures include a PVC plant in Aberdeen, Mississippi with annual capacity of approximately 1 billion pounds of suspension PVC, VCM and diaphragm chlor-alkali units at its Lake Charles, Louisiana complex with capacities of about 910 million pounds of VCM, 825 million pounds of chlorine and 910 million pounds of caustic soda, and a styrene plant there with about 570 million pounds of capacity. Westlake plans to continue supplying customers from seven other North American chlorovinyl facilities.
The company expects total pre-tax costs of approximately $415 million from these shutdowns, consisting of about $357 million of noncash accelerated depreciation, amortization and asset write-off charges, $25 million of employee severance and separation costs, and $33 million of other plant shutdown costs. Operations at the affected facilities are expected to cease in December 2025 and result in a workforce reduction of roughly 295 employees, with most charges recognized in the fourth quarter of 2025 and related cash outflows occurring over several years. Westlake also shared a press release, investor presentation and conference call update tied to its Performance & Essential Materials profitability improvement plan.
Westlake Corp director reports routine equity award vesting and share acquisition. A board member converted 1,339 restricted stock units into 1,339 shares of Westlake common stock on December 10, 2025, shown as an "M" code transaction. The form reports these shares as directly owned after the transaction.
The restricted stock units were originally granted on December 10, 2024 and vested on the first anniversary of the grant. Each unit converts into one share of common stock at an exercise price of $0, reflecting standard director equity compensation rather than an open-market purchase. The derivative position now shows zero restricted stock units remaining after this vesting and settlement.