Westlake Corporation (WLK)
NYSE: WLK · Industrial Organic Chemicals · Houston, TX · filing with the SEC since 2003
Grade5.3
◀ Past 6.7● Present 5.4▶ Future 4.0
Who owns Westlake Corporation
As filed with the SECHolders of 5% or more
0
No Schedule 13D or 13G naming this company is on file.
Directors and officers
22
report now, of 36 people on the record since 2006. Their holdings as a group are not read here.
Institutions as a whole
n/a
The record does not read the share held by managers that file Form 13F, so none is printed and no split of the rest is estimated. What it holds is the 0 named at left.
Holders of 5% or moreshare of the class, as filed
No holder of 5% or more is on file in a Schedule 13D or 13G naming this company.
What WLK reports owning in othersstakes of 5% or more, and other ties
Other ties the annual report names
Cypress Interstate Pipeline L.L.C
An investee · investee, joint venture · invested in, named in the 10-K filed Feb 26, 2026
40 subsidiaries in 2 countries, from the list filed with the 10-K filed Feb 26, 2026.
Insider tradesForm 4
9sales
0purchases
0sales on a scheduled plan
3people selling
$10.2Msold, in dollars
$0bought, in dollars
Open-market trades on Form 4 from Sep 30, 2025 to Sep 30, 2026. A scheduled plan is a selling program set in advance under SEC rule 10b5-1. The trades are listed as filed and do not feed the grade.
By calendar yearSoldBought
2026 runs to Sep 30, 2026. Dollars as filed, summed by the transaction date.
People who traded in the window3 of 37 on the roster
| Person | Role as filed | Sales | Sold | On a plan | Buys | Bought |
|---|---|---|---|---|---|---|
| Chao Albert | Executive Chairman | 5 | $6.1M | 0 | 0 | $0 |
| Bender Mark Steven | EVP & CFO | 3 | $3.6M | 0 | 0 | $0 |
| Buesinger Robert F. | EVP, PEM Segment Head | 1 | $500,000 | 0 | 0 | $0 |