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 |
|---|---|---|---|
| 10-Q | Quarterly report | Nov 4, 2026 | Sep 30, 2026 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 4, 2026 | Nov 4, 2026 |
| 8-K |
Current report
Exit or restructuring costs, Regulation FD disclosure
|
Sep 29, 2026 | Sep 24, 2026 |
| 8-K |
Current report
Officer or director change
|
Aug 31, 2026 | Aug 31, 2026 |
| CERT | Nyse texas certification | Aug 21, 2026 | — |
| 8-A12B | Filing | Aug 21, 2026 | — |
| 10-Q | Quarterly report | Aug 5, 2026 | Jun 30, 2026 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 4, 2026 | Aug 4, 2026 |
| 8-K |
Current report
Other events
|
Jul 29, 2026 | Jul 29, 2026 |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 15, 2026 | Jun 15, 2026 |
| SD | Specialized disclosure (conflict minerals) | May 18, 2026 | — |
| 8-K |
Current report
Shareholder vote results
|
May 18, 2026 | May 14, 2026 |
| 10-Q | Quarterly report | May 6, 2026 | Mar 31, 2026 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 5, 2026 | May 5, 2026 |
| 8-K |
Current report
Regulation FD disclosure
|
May 1, 2026 | Apr 27, 2026 |
| 8-K |
Current report
Officer or director change, Regulation FD disclosure
|
Apr 20, 2026 | Apr 15, 2026 |
| 8-K |
Current report
Other events
|
Apr 14, 2026 | Apr 13, 2026 |
| 8-K |
Current report
Material agreement, Agreement ended, New debt
|
Apr 6, 2026 | Apr 2, 2026 |
| 8-K |
Current report
Officer or director change
|
Apr 2, 2026 | Mar 30, 2026 |
| ARS | Annual report to shareholders | Apr 2, 2026 | Dec 31, 2025 |
| DEFA14A | Additional proxy material | Apr 2, 2026 | — |
| DEF 14A | Proxy statement | Apr 2, 2026 | May 14, 2026 |
| 10-K | Annual report | Feb 26, 2026 | Dec 31, 2025 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 24, 2026 | Feb 24, 2026 |
| 8-K |
Current report
Officer or director change, Regulation FD disclosure
|
Feb 23, 2026 | Feb 19, 2026 |
| 8-K |
Current report
Regulation FD disclosure
|
Jan 6, 2026 | Jan 6, 2026 |
| 8-K |
Current report
Exit or restructuring costs, Regulation FD disclosure
|
Dec 15, 2025 | Dec 12, 2025 |
| 8-K |
Current report
Regulation FD disclosure
|
Nov 12, 2025 | Nov 10, 2025 |
| 8-K |
Current report
Material agreement, Regulation FD disclosure
|
Nov 5, 2025 | Nov 4, 2025 |
| 424B5 | Prospectus supplement | Nov 5, 2025 | — |
| FWP | Free writing prospectus | Nov 4, 2025 | — |
| 8-K |
Current report
Regulation FD disclosure
|
Nov 4, 2025 | Nov 4, 2025 |
| 424B5 | Prospectus supplement | Nov 4, 2025 | — |
| S-3ASR | Automatic shelf registration | Oct 31, 2025 | — |
| 10-Q | Quarterly report | Oct 31, 2025 | Sep 30, 2025 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Oct 30, 2025 | Oct 30, 2025 |
| 8-K |
Current report
Regulation FD disclosure
|
Aug 26, 2025 | Aug 26, 2025 |
| 10-Q | Quarterly report | Aug 6, 2025 | Jun 30, 2025 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 5, 2025 | Aug 5, 2025 |
| 8-K |
Current report
Exit or restructuring costs
|
Jun 17, 2025 | Jun 17, 2025 |
| SD | Specialized disclosure (conflict minerals) | May 23, 2025 | — |
| 8-K |
Current report
Shareholder vote results
|
May 12, 2025 | May 8, 2025 |
| 10-Q | Quarterly report | May 2, 2025 | Mar 31, 2025 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 2, 2025 | May 2, 2025 |
| 8-K |
Current report
Officer or director change
|
Apr 16, 2025 | Apr 11, 2025 |
| ARS | Annual report to shareholders | Mar 28, 2025 | Dec 31, 2024 |
| DEFA14A | Additional proxy material | Mar 28, 2025 | — |
| DEF 14A | Proxy statement | Mar 28, 2025 | May 8, 2025 |
| 8-K |
Current report
Officer or director change
|
Mar 4, 2025 | Feb 28, 2025 |
| 10-K | Annual report | Feb 25, 2025 | Dec 31, 2024 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 24, 2025 | Feb 24, 2025 |
| 8-K |
Current report
Officer or director change
|
Dec 11, 2024 | Dec 10, 2024 |
| 10-Q | Quarterly report | Nov 6, 2024 | Sep 30, 2024 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 5, 2024 | Nov 5, 2024 |
| UPLOAD | Letter from the SEC | Sep 6, 2024 | — |
| CORRESP | Letter to the SEC | Aug 22, 2024 | — |
| 8-K |
Current report
Officer or director change
|
Aug 12, 2024 | Aug 8, 2024 |
| UPLOAD | Letter from the SEC | Aug 9, 2024 | — |
| 10-Q | Quarterly report | Aug 9, 2024 | Jun 30, 2024 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 6, 2024 | Aug 6, 2024 |
| 8-K |
Current report
Exit or restructuring costs
|
Jul 29, 2024 | Jul 29, 2024 |
| 8-K |
Current report
Officer or director change, Regulation FD disclosure
|
Jul 15, 2024 | Jul 15, 2024 |
| 8-K |
Current report
Regulation FD disclosure
|
Jul 1, 2024 | Jul 1, 2024 |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 13, 2024 | Jun 13, 2024 |
| 8-K |
Current report
Officer or director change
|
May 29, 2024 | May 22, 2024 |
| SD | Specialized disclosure (conflict minerals) | May 22, 2024 | — |
| 8-K |
Current report
Shareholder vote results
|
May 13, 2024 | May 9, 2024 |
| 10-Q | Quarterly report | May 2, 2024 | Mar 31, 2024 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 1, 2024 | May 1, 2024 |
| 8-K |
Current report
Officer or director change
|
Apr 25, 2024 | Apr 25, 2024 |
| PX14A6G | Filing | Apr 11, 2024 | — |
| 8-K |
Current report
Regulation FD disclosure
|
Apr 3, 2024 | Apr 3, 2024 |
| ARS | Annual report to shareholders | Mar 29, 2024 | Dec 31, 2023 |
| DEFA14A | Additional proxy material | Mar 29, 2024 | — |
| DEF 14A | Proxy statement | Mar 29, 2024 | May 9, 2024 |
| 10-K | Annual report | Feb 22, 2024 | Dec 31, 2023 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 20, 2024 | Feb 20, 2024 |
| 8-K |
Current report
Results of operations
|
Feb 6, 2024 | Feb 6, 2024 |
| 10-Q | Quarterly report | Nov 2, 2023 | Sep 30, 2023 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 2, 2023 | Nov 2, 2023 |
| 10-Q | Quarterly report | Aug 3, 2023 | Jun 30, 2023 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 3, 2023 | Aug 3, 2023 |
| SD | Specialized disclosure (conflict minerals) | May 31, 2023 | — |
| 8-K |
Current report
Officer or director change, Bylaw or fiscal year change, Shareholder vote results
|
May 16, 2023 | May 11, 2023 |
| S-8 | Employee stock plan registration | May 11, 2023 | — |
| 10-Q | Quarterly report | May 4, 2023 | Mar 31, 2023 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 4, 2023 | May 4, 2023 |
| PX14A6G | Filing | Apr 20, 2023 | — |
| 8-K |
Current report
Officer or director change
|
Apr 5, 2023 | Apr 3, 2023 |
| ARS | Annual report to shareholders | Mar 31, 2023 | Dec 31, 2022 |
| DEFA14A | Additional proxy material | Mar 31, 2023 | — |
| DEF 14A | Proxy statement | Mar 31, 2023 | — |
| PRE 14A | Preliminary proxy statement | Mar 20, 2023 | — |
| 10-K | Annual report | Feb 22, 2023 | Dec 31, 2022 |
| 8-K |
Current report
Officer or director change
|
Feb 21, 2023 | Feb 16, 2023 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 21, 2023 | Feb 21, 2023 |
| S-3ASR | Automatic shelf registration | Nov 3, 2022 | — |
| 10-Q | Quarterly report | Nov 3, 2022 | Sep 30, 2022 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 3, 2022 | Nov 3, 2022 |
| 8-K |
Current report
Other events
|
Aug 15, 2022 | Aug 12, 2022 |
| 10-Q | Quarterly report | Aug 3, 2022 | Jun 30, 2022 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 2, 2022 | Aug 2, 2022 |
| 8-K |
Current report
Material agreement, Agreement ended, New debt
|
Jun 9, 2022 | Jun 9, 2022 |
| SD | Specialized disclosure (conflict minerals) | May 16, 2022 | — |
| 8-K |
Current report
Shareholder vote results
|
May 13, 2022 | May 12, 2022 |
| 10-Q | Quarterly report | May 4, 2022 | Mar 31, 2022 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 3, 2022 | May 3, 2022 |
| DEFA14A | Additional proxy material | Apr 1, 2022 | — |
| DEF 14A | Proxy statement | Apr 1, 2022 | May 12, 2022 |
| 10-K | Annual report | Feb 23, 2022 | Dec 31, 2021 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 22, 2022 | Feb 22, 2022 |
| 8-K |
Current report
Bylaw or fiscal year change, Regulation FD disclosure
|
Feb 18, 2022 | Feb 18, 2022 |
| 8-K |
Current report
Acquisition or sale of assets, Regulation FD disclosure
|
Feb 1, 2022 | Feb 1, 2022 |
| 8-K |
Current report
Material agreement, Regulation FD disclosure
|
Nov 24, 2021 | Nov 24, 2021 |
| 10-Q | Quarterly report | Nov 3, 2021 | Sep 30, 2021 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 2, 2021 | Nov 2, 2021 |
| 8-K |
Current report
Acquisition or sale of assets, Regulation FD disclosure
|
Oct 1, 2021 | Oct 1, 2021 |
| UPLOAD | Letter from the SEC | Sep 23, 2021 | — |
| CORRESP | Letter to the SEC | Sep 23, 2021 | — |
| UPLOAD | Letter from the SEC | Sep 20, 2021 | — |
| 8-K |
Current report
Regulation FD disclosure
|
Aug 19, 2021 | Aug 19, 2021 |
| 8-K |
Current report
Material agreement, New debt
|
Aug 19, 2021 | Aug 19, 2021 |
| 424B5 | Prospectus supplement | Aug 6, 2021 | — |
| 8-K |
Current report
Material agreement, Regulation FD disclosure
|
Aug 6, 2021 | Aug 5, 2021 |
| FWP | Free writing prospectus | Aug 5, 2021 | — |
| 424B5 | Prospectus supplement | Aug 5, 2021 | — |
| 10-Q | Quarterly report | Aug 3, 2021 | Jun 30, 2021 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 3, 2021 | Aug 3, 2021 |
| 8-K |
Current report
Regulation FD disclosure, Other events
|
Jul 6, 2021 | Jul 4, 2021 |
| 8-K |
Current report
Material agreement, Regulation FD disclosure
|
Jun 21, 2021 | Jun 20, 2021 |
| SD | Specialized disclosure (conflict minerals) | May 21, 2021 | — |
| 8-K |
Current report
Bylaw or fiscal year change, Shareholder vote results
|
May 17, 2021 | May 13, 2021 |
| 10-Q | Quarterly report | May 5, 2021 | Mar 31, 2021 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 4, 2021 | May 4, 2021 |
| DEFA14A | Additional proxy material | Apr 2, 2021 | — |
| DEF 14A | Proxy statement | Apr 2, 2021 | May 13, 2021 |
| PRE 14A | Preliminary proxy statement | Mar 5, 2021 | May 13, 2021 |
| 10-K | Annual report | Feb 24, 2021 | Dec 31, 2020 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 23, 2021 | Feb 23, 2021 |
| 8-K |
Current report
Officer or director change
|
Nov 18, 2020 | Nov 18, 2020 |
| 10-Q | Quarterly report | Nov 4, 2020 | Sep 30, 2020 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 3, 2020 | Nov 3, 2020 |
| 8-K |
Current report
Other events
|
Sep 21, 2020 | Sep 21, 2020 |
| 8-K |
Current report
Other events
|
Sep 8, 2020 | Sep 8, 2020 |
| 8-K |
Current report
Other events
|
Aug 28, 2020 | Aug 27, 2020 |
| 10-Q | Quarterly report | Aug 6, 2020 | Jun 30, 2020 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 6, 2020 | Aug 6, 2020 |
| 8-K |
Current report
Other events
|
Jul 14, 2020 | Jul 14, 2020 |
| 8-K |
Current report
Material agreement, New debt
|
Jun 12, 2020 | Jun 12, 2020 |
| 8-K |
Current report
Material agreement, Regulation FD disclosure
|
Jun 10, 2020 | Jun 9, 2020 |
| 424B5 | Prospectus supplement | Jun 10, 2020 | — |
| FWP | Free writing prospectus | Jun 9, 2020 | — |
| 424B5 | Prospectus supplement | Jun 9, 2020 | — |
| 8-K |
Current report
Other events
|
Jun 4, 2020 | Jun 4, 2020 |
| SD | Specialized disclosure (conflict minerals) | May 22, 2020 | — |
| 8-K |
Current report
Shareholder vote results
|
May 18, 2020 | May 15, 2020 |
| 10-Q | Quarterly report | May 6, 2020 | Mar 31, 2020 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 4, 2020 | May 4, 2020 |
| DEFA14A | Additional proxy material | Apr 3, 2020 | — |
| DEF 14A | Proxy statement | Apr 3, 2020 | May 15, 2020 |
| 8-K |
Current report
Other events
|
Mar 20, 2020 | Mar 20, 2020 |
| 10-K | Annual report | Feb 19, 2020 | Dec 31, 2019 |
| 8-K |
Current report
Officer or director change
|
Feb 18, 2020 | Feb 13, 2020 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 18, 2020 | Feb 18, 2020 |
| 8-K |
Current report
Officer or director change
|
Jan 31, 2020 | Jan 27, 2020 |
| 8-K |
Current report
Other events
|
Nov 18, 2019 | Nov 12, 2019 |
| S-3ASR | Automatic shelf registration | Nov 7, 2019 | — |
| 10-Q | Quarterly report | Nov 6, 2019 | Sep 30, 2019 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 5, 2019 | Nov 5, 2019 |
| 8-K |
Current report
Other events
|
Oct 30, 2019 | Oct 29, 2019 |
| 10-Q | Quarterly report | Aug 6, 2019 | Jun 30, 2019 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 6, 2019 | Aug 6, 2019 |
| CERT | Nyse certification | Jul 22, 2019 | — |
| 8-A12B | Filing | Jul 17, 2019 | — |
| 8-K |
Current report
Material agreement, New debt
|
Jul 17, 2019 | Jul 17, 2019 |
| 424B5 | Prospectus supplement | Jul 12, 2019 | — |
| 8-K |
Current report
Material agreement, Regulation FD disclosure
|
Jul 11, 2019 | Jul 10, 2019 |
| FWP | Free writing prospectus | Jul 10, 2019 | — |
| 8-K |
Current report
Regulation FD disclosure
|
Jul 10, 2019 | Jul 10, 2019 |
| 424B5 | Prospectus supplement | Jul 10, 2019 | — |
| 8-K |
Current report
Results of operations
|
Jul 1, 2019 | Jul 1, 2019 |
| SD | Specialized disclosure (conflict minerals) | May 24, 2019 | — |
| 8-K |
Current report
Shareholder vote results
|
May 21, 2019 | May 17, 2019 |
| 10-Q | Quarterly report | May 2, 2019 | Mar 31, 2019 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 2, 2019 | May 2, 2019 |
| DEFA14A | Additional proxy material | Apr 5, 2019 | — |
| DEF 14A | Proxy statement | Apr 5, 2019 | May 17, 2019 |
| 10-K | Annual report | Feb 20, 2019 | Dec 31, 2018 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 19, 2019 | Feb 19, 2019 |
| 8-K |
Current report
Regulation FD disclosure
|
Jan 2, 2019 | Jan 2, 2019 |
| 10-Q | Quarterly report | Nov 6, 2018 | Sep 30, 2018 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 6, 2018 | Nov 6, 2018 |
| 8-K |
Current report
Regulation FD disclosure
|
Sep 25, 2018 | Sep 25, 2018 |
| POSASR | Filing | Sep 20, 2018 | — |
| 8-K |
Current report
Officer or director change
|
Aug 17, 2018 | Aug 17, 2018 |
| 8-K |
Current report
Other events
|
Aug 17, 2018 | Aug 17, 2018 |
| 10-Q | Quarterly report | Aug 2, 2018 | Jun 30, 2018 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 2, 2018 | Aug 2, 2018 |
| 8-K |
Current report
Material agreement, Agreement ended, New debt
|
Jul 26, 2018 | Jul 24, 2018 |
| SD | Specialized disclosure (conflict minerals) | May 22, 2018 | — |
Showing 200 filings, the most recent 200. 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.