Who owns Westlake (WLK)
Which tracked institutional funds hold WLK, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See WLK company fundamentals →
Ownership as of the 2026-Q2 13F filings (latest filed 2026-09-22). 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
62 tracked funds added or opened WLK while 150 trimmed or exited it between 2026-Q1 and 2026-Q2 — the tape is split. When large holders disagree on a name, the funds moving first are sometimes ahead of the story.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
WLK’s largest tracked holder by dollar value, BlackRock, Inc., sizes it at 0.0% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.0pp gap the other way — the median holder sizes WLK more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in WLK divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2026-Q1 and 2026-Q2, across 330 tracked filers holding WLK, 184 increased or opened the position and 199 reduced or closed it; over the same quarter, there were no open-market insider Form 4s.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in WLK between the 2026-Q1 and 2026-Q2 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 37
- ExodusPoint Capital Management, LP$24M
- Qube Research & Technologies Ltd$23M
- Jupiter Topco LLC$20M
- Jump Financial, LLC$15M
- Campbell & CO Investment Adviser LLC$11M
- Lighthouse Investment Partners, LLC$10M
Full exits 39
- Holocene Advisors, LP$85M
- JANUS HENDERSON GROUP PLC$32M
- DEPRINCE RACE & ZOLLO INC$24M
- TEACHERS RETIREMENT SYSTEM OF THE STATE OF KENTUCKY$21M
- Ceredex Value Advisors LLC$21M
- Yaupon Capital Management LP$13M
Largest adds
- AQR CAPITAL MANAGEMENT LLC$84M
- BlackRock, Inc.$32M
- MILLENNIUM MANAGEMENT LLC$17M
- Susquehanna Portfolio Strategies, LLC$15M
- JACOBS LEVY EQUITY MANAGEMENT, INC$11M
- BNP PARIBAS FINANCIAL MARKETS$6M
Largest trims
- Orbis Allan Gray Ltd$466M
- Capital World Investors$284M
- WELLINGTON MANAGEMENT GROUP LLP$199M
- PRICE T ROWE ASSOCIATES INC /MD/$120M
- FMR LLC$118M
- BRANDES INVESTMENT PARTNERS, LP$100M
Institutional holders
One row per tracked fund, most shares held first (every row is from one quarter; reported value breaks ties). “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding.
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| BlackRock, Inc. added | 3,294,162 | $240M | 8.7% | 2026-Q2 |
| Capital World Investors trimmed | 2,842,348 | $207M | 7.5% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 2,206,676 | $161M | 5.8% | 2026-Q2 |
| Orbis Allan Gray Ltd trimmed | 2,084,364 | $152M | 5.5% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP added | 2,051,554 | $150M | 5.4% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC trimmed | 1,752,627 | $128M | 4.6% | 2026-Q2 |
| BRANDES INVESTMENT PARTNERS, LP trimmed | 1,572,939 | $115M | 4.1% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 1,570,453 | $115M | 4.1% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 1,464,223 | $107M | 3.9% | 2026-Q2 |
| STATE STREET CORP added | 1,453,407 | $106M | 3.8% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC trimmed | 1,280,873 | $94M | 3.4% | 2026-Q2 |
| CITADEL ADVISORS LLC added | 1,054,868 | $77M | 2.8% | 2026-Q2 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. added | 1,023,403 | $75M | 2.7% | 2026-Q2 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC trimmed | 817,207 | $60M | 2.1% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 718,597 | $52M | 1.9% | 2026-Q2 |
| JACOBS LEVY EQUITY MANAGEMENT, INC added | 709,355 | $52M | 1.9% | 2026-Q2 |
| BALYASNY ASSET MANAGEMENT L.P. added | 625,859 | $46M | 1.6% | 2026-Q2 |
| Woodline Partners LP added | 451,986 | $33M | 1.2% | 2026-Q2 |
| Nuveen, LLC trimmed | 446,479 | $33M | 1.2% | 2026-Q2 |
| MORGAN STANLEY trimmed | 437,571 | $32M | 1.2% | 2026-Q2 |
| UBS Group AG trimmed | 431,633 | $32M | 1.1% | 2026-Q2 |
| SCHRODER INVESTMENT MANAGEMENT GROUP added | 375,889 | $28M | 1.0% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC added | 366,074 | $27M | 1.0% | 2026-Q2 |
| FMR LLC trimmed | 361,243 | $26M | 1.0% | 2026-Q2 |
| ExodusPoint Capital Management, LP added | 327,195 | $24M | 0.9% | 2026-Q2 |
| Qube Research & Technologies Ltd added | 321,718 | $23M | 0.8% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 318,823 | $23M | 0.8% | 2026-Q2 |
| Erste Asset Management GmbH trimmed | 305,000 | $23M | 0.8% | 2026-Q2 |
| VAN LANSCHOT KEMPEN INVESTMENT MANAGEMENT N.V. added | 268,434 | $20M | 0.7% | 2026-Q2 |
| Jupiter Topco LLC new | 267,748 | $20M | 0.7% | 2026-Q2 |
| NORTHERN TRUST CORP trimmed | 262,926 | $19M | 0.7% | 2026-Q2 |
| ROBOTTI ROBERT added | 235,379 | $17M | 0.6% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ trimmed | 232,213 | $17M | 0.6% | 2026-Q2 |
| Susquehanna Portfolio Strategies, LLC added | 230,396 | $17M | 0.6% | 2026-Q2 |
| ProShare Advisors LLC trimmed | 228,319 | $17M | 0.6% | 2026-Q2 |
| NORGES BANK trimmed | 214,101 | $16M | 0.6% | 2026-Q2 |
| Jump Financial, LLC added | 209,861 | $15M | 0.6% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO added | 209,650 | $15M | 0.6% | 2026-Q2 |
| D. E. Shaw & Co., Inc. trimmed | 200,534 | $15M | 0.5% | 2026-Q2 |
| Russell Investments Group, Ltd. added | 194,362 | $14M | 0.5% | 2026-Q2 |
| Invesco Ltd. added | 190,951 | $14M | 0.5% | 2026-Q2 |
| Cerity Partners LLC added | 166,436 | $12M | 0.4% | 2026-Q2 |
| Bank of New York Mellon Corp trimmed | 163,455 | $12M | 0.4% | 2026-Q2 |
| JPMORGAN CHASE & CO added | 163,287 | $12M | 0.4% | 2026-Q2 |
| Allspring Global Investments Holdings, LLC trimmed | 163,075 | $12M | 0.4% | 2026-Q2 |
| SPROTT INC. added | 160,110 | $12M | 0.4% | 2026-Q2 |
| Campbell & CO Investment Adviser LLC added | 148,180 | $11M | 0.4% | 2026-Q2 |
| WELLINGTON MANAGEMENT GROUP LLP trimmed | 141,816 | $10M | 0.4% | 2026-Q2 |
| Lighthouse Investment Partners, LLC added | 135,361 | $10M | 0.4% | 2026-Q2 |
| Recurrent Investment Advisors LLC added | 128,771 | $9M | 0.3% | 2026-Q2 |
| Quantinno Capital Management LP added | 123,228 | $9M | 0.3% | 2026-Q2 |
| MARSHALL WACE, LLP added | 111,574 | $8M | 0.3% | 2026-Q2 |
| TUDOR INVESTMENT CORP ET AL added | 110,710 | $8M | 0.3% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN trimmed | 105,936 | $8M | 0.3% | 2026-Q2 |
| MACKENZIE FINANCIAL CORP added | 104,903 | $8M | 0.3% | 2026-Q2 |
| ROYAL BANK OF CANADA trimmed | 96,772 | $7M | 0.3% | 2026-Q2 |
| Thomist Capital Management, LP added | 96,200 | $7M | 0.3% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS added | 94,400 | $7M | 0.2% | 2026-Q2 |
| Point72 Asset Management, L.P. added | 89,731 | $7M | 0.2% | 2026-Q2 |
| Alberta Investment Management Corp added | 89,200 | $7M | 0.2% | 2026-Q2 |
| RHUMBLINE ADVISERS trimmed | 86,305 | $6M | 0.2% | 2026-Q2 |
| Walleye Capital LLC added | 82,847 | $6M | 0.2% | 2026-Q2 |
| Meiji Yasuda Asset Management Co Ltd. added | 82,778 | $6M | 0.2% | 2026-Q2 |
| Squarepoint Ops LLC added | 79,967 | $6M | 0.2% | 2026-Q2 |
| NATIXIS trimmed | 77,117 | $6M | 0.2% | 2026-Q2 |
| Tidal Investments LLC added | 76,055 | $6M | 0.2% | 2026-Q2 |
| PDT Partners, LLC | 75,777 | $6M | 0.2% | 2026-Q2 |
| PRINCIPAL FINANCIAL GROUP INC added | 75,653 | $6M | 0.2% | 2026-Q2 |
| AGMAN CAPITAL LLC trimmed | 71,465 | $5M | 0.2% | 2026-Q2 |
| Engineers Gate Manager LP added | 71,301 | $5M | 0.2% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. trimmed | 65,993 | $8M | 0.3% | 2026-Q2 |
| Swiss National Bank trimmed | 64,200 | $5M | 0.2% | 2026-Q2 |
| Turas Capital Management LP new | 58,800 | $4M | 0.2% | 2026-Q2 |
| Assenagon Asset Management S.A. added | 55,289 | $4M | 0.1% | 2026-Q2 |
| Merewether Investment Management, LP trimmed | 53,439 | $4M | 0.1% | 2026-Q2 |
| AXQ CAPITAL, LP added | 51,437 | $4M | 0.1% | 2026-Q2 |
| Legal & General Group Plc trimmed | 50,025 | $4M | 0.1% | 2026-Q2 |
| Mariner, LLC added | 47,319 | $3M | 0.1% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP trimmed | 45,357 | $3M | 0.1% | 2026-Q2 |
| NEW YORK STATE COMMON RETIREMENT FUND trimmed | 40,926 | $3M | 0.1% | 2026-Q2 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE added | 37,155 | $3M | 0.1% | 2026-Q2 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed | 36,900 | $3M | 0.1% | 2026-Q2 |
| CITIGROUP INC trimmed | 36,569 | $3M | 0.1% | 2026-Q2 |
| STATE OF WISCONSIN INVESTMENT BOARD added | 35,823 | $3M | 0.1% | 2026-Q2 |
| OCCUDO QUANTITATIVE STRATEGIES LP trimmed | 35,695 | $3M | 0.1% | 2026-Q2 |
| BANK OF MONTREAL /CAN/ trimmed | 35,590 | $3M | 0.1% | 2026-Q2 |
| HITE Hedge Asset Management LLC trimmed | 34,589 | $3M | 0.1% | 2026-Q2 |
| Retirement Systems of Alabama trimmed | 34,454 | $3M | 0.1% | 2026-Q2 |
| LOS ANGELES CAPITAL MANAGEMENT LLC added | 32,600 | $2M | 0.1% | 2026-Q2 |
| ABN AMRO INVESTMENT SOLUTIONS new | 31,597 | $2M | 0.1% | 2026-Q2 |
| AMERIPRISE FINANCIAL INC added | 31,288 | $2M | 0.1% | 2026-Q2 |
| WORLDQUANT MILLENNIUM ADVISORS LLC added | 31,204 | $2M | 0.1% | 2026-Q2 |
| VANGUARD ASSET MANAGEMENT, Ltd trimmed | 30,040 | $2M | 0.1% | 2026-Q2 |
| ENVESTNET ASSET MANAGEMENT INC added | 29,586 | $2M | 0.1% | 2026-Q2 |
| FIRST TRUST ADVISORS LP trimmed | 27,496 | $2M | 0.1% | 2026-Q2 |
| Freestone Grove Partners LP new | 27,248 | $2M | 0.1% | 2026-Q2 |
| BARCLAYS PLC added | 26,524 | $2M | 0.1% | 2026-Q2 |
| MERCER GLOBAL ADVISORS INC /ADV added | 26,477 | $2M | 0.1% | 2026-Q2 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP added | 26,155 | $2M | 0.1% | 2026-Q2 |
| STIFEL FINANCIAL CORP added | 26,128 | $2M | 0.1% | 2026-Q2 |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.