Westlake Corp SEC filings WLK
Westlake Corp has 1,010 filings in SEC EDGAR's recent list, going back to Feb 20, 2015. Its latest annual report, Form ARS, was filed on Apr 2, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Nov 4, 2026, covering the quarter ended Sep 30, 2026. The most recent current report (Form 8-K) was filed on Nov 4, 2026 (results of operations, regulation fd disclosure). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| 424B5 | Prospectus supplement | Nov 5, 2025 | — |
| FWP | Free writing prospectus | Nov 4, 2025 | — |
| 424B5 | Prospectus supplement | Nov 4, 2025 | — |
| S-3ASR | Automatic shelf registration | Oct 31, 2025 | — |
| S-8 | Employee stock plan registration | May 11, 2023 | — |
| S-3ASR | Automatic shelf registration | Nov 3, 2022 | — |
| 424B5 | Prospectus supplement | Aug 6, 2021 | — |
| FWP | Free writing prospectus | Aug 5, 2021 | — |
| 424B5 | Prospectus supplement | Aug 5, 2021 | — |
| 424B5 | Prospectus supplement | Jun 10, 2020 | — |
| FWP | Free writing prospectus | Jun 9, 2020 | — |
| 424B5 | Prospectus supplement | Jun 9, 2020 | — |
| S-3ASR | Automatic shelf registration | Nov 7, 2019 | — |
| 424B5 | Prospectus supplement | Jul 12, 2019 | — |
| FWP | Free writing prospectus | Jul 10, 2019 | — |
| 424B5 | Prospectus supplement | Jul 10, 2019 | — |
| 424B5 | Prospectus supplement | Nov 14, 2017 | — |
| FWP | Free writing prospectus | Nov 13, 2017 | — |
| 424B5 | Prospectus supplement | Nov 13, 2017 | — |
| 424B5 | Prospectus supplement | Mar 27, 2017 | — |
| S-4 | Registration for a merger or exchange | Mar 13, 2017 | — |
| S-3ASR | Automatic shelf registration | Sep 8, 2016 | — |
Showing 22 filings. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.
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Company profile
- Industry
- Industrial Organic Chemicals (SIC 2860)
- Listed as
- WLK (NYSE)
- Fiscal year ends
- December 31
- Incorporated in
- DE
- Headquarters
- Houston, TX
- SEC filer status
- Large accelerated filer
- SEC CIK
- 1262823
- Former names
- WESTLAKE CHEMICAL CORP (until Feb 1, 2022)
Other Industrial Organic Chemicals companies
Source: SEC EDGAR filings. This is company-reported data, not investment advice.