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WLK in the 13F filings

Westlake Corporation · CUSIP 960413102

Sector · Materials
Quarter
Q2 2026Q1 2026Q4 2025Q3 2025Q2 2025Q1 2025Q4 2024Q3 2024Q2 2024Q1 2024Q4 2023Q3 2023
Quarter end
31 Dec 2025
the date the book describes
Filed
19 Feb 2026
latest of these filings; the earliest 4 Feb 2026
Managers listing it
28
at least, of 95 tracked, among listed positions
Comparable managers
92
filed both Q3 2025 and Q4 2025; 6 listed it in both
Shares listed
13,535,526
combined, among listed positions
Reported value
$1.0bn
combined, at the quarter end

Among the 92 comparable managers: 18 buyers (opened or added shares) and 18 sellers (trimmed or exited), at least, among listed positions. Their net change in shares was +5,809,091.

Managers listing WLK in Q4 2025

Share of 13F value is the position’s reported value over everything the manager reported that quarter. The share change is against Q3 2025, and only where both filings list the position. A rise in value with no rise in shares is the price, not buying.

28 of 28 holders

ActionFiling
Wellington Management Group LLP4,220,717$312m0.05%Added+4,163,20717 Feb 2026 (the filing on sec.gov)
T. Rowe Price Associates Inc2,208,715$163munder 0.1%Added+57217 Feb 2026 (the filing on sec.gov)
Capital World Investors2,171,324$161munder 0.1%Newnew11 Feb 2026 (the filing on sec.gov)
Holocene Advisors LP1,220,622$90m0.19%Added+366,43817 Feb 2026 (the filing on sec.gov)
Woodline Partners LP628,159$46m0.18%Added+434,37317 Feb 2026 (the filing on sec.gov)
D. E. Shaw & Co.486,281$36munder 0.1%Added+326,27217 Feb 2026 (the filing on sec.gov)
Millennium Management LLC427,754$32munder 0.1%Added+321,43417 Feb 2026 (the filing on sec.gov)
Voloridge Investment Management LLC348,953$26m0.09%Trimmed-45,35417 Feb 2026 (the filing on sec.gov)
Janus Henderson Group Ltd334,593$25munder 0.1%Trimmed-31,39117 Feb 2026 (the filing on sec.gov)
Fidelity (FMR LLC)228,843$17munder 0.1%Trimmed-85,50717 Feb 2026 (the filing on sec.gov)
Invesco Ltd213,157$16munder 0.1%Added+78,45819 Feb 2026 (the filing on sec.gov)
Citadel Advisors LLC203,303$15munder 0.1%Trimmed-997,54817 Feb 2026 (the filing on sec.gov)
Two Sigma Investments LP198,379$15munder 0.1%Added+95,41417 Feb 2026 (the filing on sec.gov)
ExodusPoint Capital Management LP154,391$11m0.09%Newnew17 Feb 2026 (the filing on sec.gov)
Two Sigma Advisers LP144,700$11munder 0.1%Added+71,00017 Feb 2026 (the filing on sec.gov)
AllianceBernstein LP68,448$5.1munder 0.1%Added+1,68617 Feb 2026 (the filing on sec.gov)
PDT Partners LLC64,977$4.8m0.31%Added+45,45717 Feb 2026 (the filing on sec.gov)
Walleye Capital LLC47,657$3.5munder 0.1%Trimmed-100,66013 Feb 2026 (the filing on sec.gov)
Quantbot Technologies LP39,607$2.9m0.10%Trimmed-17,17810 Feb 2026 (the filing on sec.gov)
Hudson Bay Capital Management LP30,443$2.3munder 0.1%Added+26,94713 Feb 2026 (the filing on sec.gov)
Verition Fund Management LLC26,078$1.9munder 0.1%Trimmed-1,07713 Feb 2026 (the filing on sec.gov)
Susquehanna International Group LLP23,801$1.8munder 0.1%Added+14,95717 Feb 2026 (the filing on sec.gov)
AQR Capital Management LLC20,535$1.5munder 0.1%Trimmed-31,98717 Feb 2026 (the filing on sec.gov)
Brevan Howard Capital Management LP9,468$700kunder 0.1%Added+2,06217 Feb 2026 (the filing on sec.gov)
Schonfeld Strategic Advisors LLC6,012$445kunder 0.1%Trimmed-39,97817 Feb 2026 (the filing on sec.gov)
Page 1 of 2

Largest increases and reductions, by shares

Q3 2025 to Q4 2025, among managers that listed it in both quarters or opened it.

Increases

Reductions

New positions and exits

At least these many: a manager is shown exiting only where its own filing shows the position gone.

New (4)

Exited (8)

Ownership over time

Every quarter on file. A quarter-end value moves with the price as well as with the shares held; buyers and sellers count comparable managers, by shares.
8 in Q3 2024 to 7 in Q2 2026

Tracked managers listing it, at least.

0510152014201620182020202220242026
the quarter shown share split complete books; unmarked quarters rest on listed positionsClick a quarter to open it.
WLK by quarter
QuarterHoldersReported valueBuyersSellers
Q2 20137$113mn.a.n.a.
Q3 20139$189mn.a.n.a.
Q4 201310$271mn.a.n.a.
Q1 201410$267mn.a.n.a.
Q2 20148$254mn.a.n.a.
Q3 201410$614mn.a.n.a.
Q4 20149$288mn.a.n.a.
Q1 201512$503mn.a.n.a.
Q2 201510$513mn.a.n.a.
Q3 20159$402mn.a.n.a.
Q4 20156$274mn.a.n.a.
Q1 20165$192mn.a.n.a.
Q2 20166$223mn.a.n.a.
Q3 201610$340mn.a.n.a.
Q4 201612$357mn.a.n.a.
Q1 20179$456mn.a.n.a.
Q2 20176$502mn.a.n.a.
Q3 201712$612mn.a.n.a.
Q4 20177$914mn.a.n.a.
Q1 201811$912mn.a.n.a.
Q2 20189$1.1bnn.a.n.a.
Q3 20189$937mn.a.n.a.
Q4 20188$763mn.a.n.a.
Q1 201910$881mn.a.n.a.
Q2 20198$839mn.a.n.a.
Q3 20198$911mn.a.n.a.
Q4 20197$682mn.a.n.a.
Q1 20207$305mn.a.n.a.
Q2 20208$611mn.a.n.a.
Q3 20205$794mn.a.n.a.
Q4 20208$996mn.a.n.a.
Q1 202110$794mn.a.n.a.
Q2 20217$325mn.a.n.a.
Q3 202112$344mn.a.n.a.
Q4 202111$315mn.a.n.a.
Q1 20228$416mn.a.n.a.
Q2 202210$373mn.a.n.a.
Q3 202211$401mn.a.n.a.
Q4 20228$681mn.a.n.a.
Q1 20238$935mn.a.n.a.
Q2 20237$709mn.a.n.a.
Q3 20238$858mn.a.n.a.
Q4 20239$963m44
Q1 20248$965m72
Q2 20247$832m43
Q3 20248$306m72
Q4 202410$430m81
Q1 202511$442m101
Q2 20257$252m53
Q3 20257$165m53
Q4 20259$654m1818
Q1 202610$1.2bn1518
Q2 20267$318m2014

Compare with…

Holders over time, buyers and sellers, and the managers holding both, side by side for up to four stocks.

WLK and LIN →WLK and GLW →WLK and HWM →Choose a stock to compare with WLK →

How much of the picture this is

A 13F is a manager’s long US-listed equity book at a quarter end, filed up to 45 days later. It shows no shorts, cash, bonds or performance, and it is never today’s portfolio. Large books are listed to their largest positions, so a manager missing from this table may still hold a small position below that line. These are 95 tracked managers, not the institutional market.

Which funds own WLK, latest filings →Back to the 13F Explorer →