Who owns CSTM (CSTM)
Which tracked institutional funds hold CSTM, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See CSTM company fundamentals →
Ownership as of the 2026-Q1 13F filings. 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
The tracked-fund tape on CSTM is one-sided between 2025-Q4 and 2026-Q1: 154 added or opened and 39 trimmed or exited — on balance accumulating.
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
CSTM’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 CSTM more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in CSTM 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 2025-Q4 and 2026-Q1, across 312 tracked filers holding CSTM, 199 increased or opened the position and 111 reduced or closed it; over the same quarter, open-market insider Form 4s were net purchases.
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 CSTM between the 2025-Q4 and 2026-Q1 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 45
- VANGUARD PORTFOLIO MANAGEMENT LLC$97M
- WESTWOOD HOLDINGS GROUP INC$34M
- Kinetic Partners Management, LP$32M
- WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC$23M
- Bayberry Capital Partners LP$21M
- Bridgewater Associates, LP$12M
Full exits 10
- VANGUARD GROUP INC$71M
- Nut Tree Capital Management, LP$61M
- CAPSTONE INVESTMENT ADVISORS, LLC$23M
- Empowered Funds, LLC$13M
- TUDOR INVESTMENT CORP ET AL$9M
- WELLINGTON MANAGEMENT GROUP LLP$9M
Largest adds
- Bpifrance SA$72M
- ARROWSTREET CAPITAL, LIMITED PARTNERSHIP$71M
- T. Rowe Price Investment Management, Inc.$66M
- BlackRock, Inc.$60M
- HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND$47M
- ALLIANCEBERNSTEIN L.P.$41M
Largest trims
- MILLENNIUM MANAGEMENT LLC$33M
- FMR LLC$28M
- Encompass Capital Advisors LLC$27M
- BRIDGEWAY CAPITAL MANAGEMENT, LLC$16M
- MOORE CAPITAL MANAGEMENT, LP$14M
- Boston Partners$9M
Institutional holders
One row per tracked fund, largest reported value first. “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding. Rows marked stale are from an earlier filing than the security’s latest quarter — that fund is absent from the newest snapshot (position exited, or reported under a different name).
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| BlackRock, Inc. trimmed | 12,964,203 | $319M | 10.2% | 2026-Q1 |
| Bpifrance SA | 12,593,903 | $310M | 9.9% | 2026-Q1 |
| FMR LLC trimmed | 6,961,661 | $171M | 5.5% | 2026-Q1 |
| T. Rowe Price Investment Management, Inc. added | 3,960,819 | $97M | 3.1% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 3,927,097 | $97M | 3.1% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC trimmed | 3,470,091 | $85M | 2.7% | 2026-Q1 |
| D. E. Shaw & Co., Inc. added | 3,234,576 | $80M | 2.6% | 2026-Q1 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 3,228,027 | $79M | 2.5% | 2026-Q1 |
| MORGAN STANLEY trimmed | 3,196,054 | $79M | 2.5% | 2026-Q1 |
| Nuveen, LLC trimmed | 2,827,731 | $70M | 2.2% | 2026-Q1 |
| STATE STREET CORP added | 2,763,495 | $68M | 2.2% | 2026-Q1 |
| Encompass Capital Advisors LLC trimmed | 2,477,278 | $61M | 2.0% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC added | 2,085,479 | $51M | 1.6% | 2026-Q1 |
| AQR CAPITAL MANAGEMENT LLC added | 2,060,942 | $51M | 1.6% | 2026-Q1 |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND added | 2,056,336 | $51M | 1.6% | 2026-Q1 |
| JPMORGAN CHASE & CO trimmed | 2,051,930 | $47M | 1.5% | 2026-Q1 |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. trimmed | 1,913,433 | $47M | 1.5% | 2026-Q1 |
| BRIGHTLINE CAPITAL MANAGEMENT, LLC added | 1,847,000 | $45M | 1.5% | 2026-Q1 |
| ALLIANCEBERNSTEIN L.P. added | 2,317,008 | $44M | 1.4% | 2026-Q1 |
| SCOPUS ASSET MANAGEMENT, L.P. trimmed | 1,681,708 | $41M | 1.3% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 1,668,451 | $41M | 1.3% | 2026-Q1 |
| SG Americas Securities, LLC added | 1,497,460 | $37M | 1.2% | 2026-Q1 |
| WESTWOOD HOLDINGS GROUP INC trimmed | 1,401,416 | $34M | 1.1% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 1,371,776 | $34M | 1.1% | 2026-Q1 |
| Kinetic Partners Management, LP new | 1,312,400 | $32M | 1.0% | 2026-Q1 |
| ACADIAN ASSET MANAGEMENT LLC added | 1,272,871 | $31M | 1.0% | 2026-Q1 |
| BEACONLIGHT CAPITAL, LLC trimmed | 1,171,812 | $29M | 0.9% | 2026-Q1 |
| Point72 Asset Management, L.P. added | 1,005,203 | $25M | 0.8% | 2026-Q1 |
| NORTHERN TRUST CORP added | 977,583 | $24M | 0.8% | 2026-Q1 |
| WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC new | 918,090 | $23M | 0.7% | 2026-Q1 |
| Cannell & Spears LLC trimmed | 909,200 | $22M | 0.7% | 2026-Q1 |
| Allianz Asset Management GmbH added | 893,937 | $22M | 0.7% | 2026-Q1 |
| Engineers Gate Manager LP trimmed | 884,103 | $22M | 0.7% | 2026-Q1 |
| Bayberry Capital Partners LP added | 874,000 | $21M | 0.7% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC trimmed | 855,664 | $21M | 0.7% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 851,222 | $21M | 0.7% | 2026-Q1 |
| Penn Capital Management Company, LLC added | 844,934 | $21M | 0.7% | 2026-Q1 |
| JANE STREET GROUP, LLC added | 832,491 | $20M | 0.7% | 2026-Q1 |
| Soapstone Management L.P. trimmed | 800,000 | $20M | 0.6% | 2026-Q1 |
| BALYASNY ASSET MANAGEMENT L.P. added | 795,413 | $20M | 0.6% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC trimmed | 783,237 | $19M | 0.6% | 2026-Q1 |
| CITADEL ADVISORS LLC added | 770,608 | $19M | 0.6% | 2026-Q1 |
| COOPER CREEK PARTNERS MANAGEMENT LLC trimmed | 764,205 | $19M | 0.6% | 2026-Q1 |
| PANAGORA ASSET MANAGEMENT INC added | 704,840 | $17M | 0.6% | 2026-Q1 |
| Mountaineer Partners Management, LLC trimmed | 658,490 | $16M | 0.5% | 2026-Q1 |
| FEDERATED HERMES, INC. added | 652,658 | $16M | 0.5% | 2026-Q1 |
| NEW YORK STATE COMMON RETIREMENT FUND added | 570,187 | $14M | 0.4% | 2026-Q1 |
| Kailix Advisors LLC trimmed | 494,400 | $14M | 0.4% | 2026-Q1 |
| Fisher Asset Management, LLC added | 539,451 | $13M | 0.4% | 2026-Q1 |
| HRT FINANCIAL LP added | 518,832 | $13M | 0.4% | 2026-Q1 |
| Bridgewater Associates, LP added | 502,971 | $12M | 0.4% | 2026-Q1 |
| ArrowMark Colorado Holdings LLC trimmed | 497,379 | $12M | 0.4% | 2026-Q1 |
| Trexquant Investment LP added | 483,077 | $12M | 0.4% | 2026-Q1 |
| UBS Group AG trimmed | 471,495 | $12M | 0.4% | 2026-Q1 |
| Qube Research & Technologies Ltd added | 470,929 | $12M | 0.4% | 2026-Q1 |
| Russell Investments Group, Ltd. added | 465,397 | $11M | 0.4% | 2026-Q1 |
| JANUS HENDERSON GROUP PLC added | 439,301 | $11M | 0.3% | 2026-Q1 |
| Hudson Bay Capital Management LP | 401,989 | $10M | 0.3% | 2026-Q1 |
| Bank of New York Mellon Corp trimmed | 397,737 | $10M | 0.3% | 2026-Q1 |
| DANSKE BANK A/S trimmed | 395,440 | $10M | 0.3% | 2026-Q1 |
| ALGERT GLOBAL LLC trimmed | 358,938 | $9M | 0.3% | 2026-Q1 |
| WHITEBOX ADVISORS LLC trimmed | 346,660 | $9M | 0.3% | 2026-Q1 |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ added | 337,844 | $8M | 0.3% | 2026-Q1 |
| SummitTX Capital, L.P. trimmed | 330,242 | $8M | 0.3% | 2026-Q1 |
| RAYMOND JAMES FINANCIAL INC added | 328,788 | $8M | 0.3% | 2026-Q1 |
| BEACON INVESTMENT ADVISORS LLC trimmed | 326,966 | $8M | 0.3% | 2026-Q1 |
| Hillsdale Investment Management Inc. new | 316,700 | $8M | 0.2% | 2026-Q1 |
| FRANKLIN RESOURCES INC added | 289,324 | $7M | 0.2% | 2026-Q1 |
| TWO SIGMA INVESTMENTS, LP added | 288,900 | $7M | 0.2% | 2026-Q1 |
| CVFG LLC new | 273,220 | $7M | 0.2% | 2026-Q1 |
| IEQ CAPITAL, LLC added | 266,112 | $7M | 0.2% | 2026-Q1 |
| OCCUDO QUANTITATIVE STRATEGIES LP added | 203,298 | $6M | 0.2% | 2026-Q1 |
| GW&K Investment Management, LLC trimmed | 257,588 | $6M | 0.2% | 2026-Q1 |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC trimmed | 252,168 | $6M | 0.2% | 2026-Q1 |
| Swiss National Bank trimmed | 245,400 | $6M | 0.2% | 2026-Q1 |
| Creative Planning added | 242,751 | $6M | 0.2% | 2026-Q1 |
| Voleon Capital Management LP trimmed | 239,501 | $6M | 0.2% | 2026-Q1 |
| LSV ASSET MANAGEMENT trimmed | 233,500 | $6M | 0.2% | 2026-Q1 |
| SEI INVESTMENTS CO added | 231,774 | $6M | 0.2% | 2026-Q1 |
| Edgestream Partners, L.P. added | 226,292 | $6M | 0.2% | 2026-Q1 |
| BANK OF MONTREAL /CAN/ trimmed | 207,106 | $5M | 0.2% | 2026-Q1 |
| BW Gestao de Investimentos Ltda. trimmed | 207,096 | $5M | 0.2% | 2026-Q1 |
| THORNBURG INVESTMENT MANAGEMENT INC trimmed | 205,467 | $5M | 0.2% | 2026-Q1 |
| KBC Group NV added | 197,790 | $5M | 0.2% | 2026-Q1 |
| Sequoia Financial Advisors, LLC added | 197,198 | $5M | 0.2% | 2026-Q1 |
| STATE OF WISCONSIN INVESTMENT BOARD added | 192,552 | $5M | 0.2% | 2026-Q1 |
| Rockingstone Advisors LLC trimmed | 191,837 | $5M | 0.2% | 2026-Q1 |
| MACKENZIE FINANCIAL CORP added | 181,470 | $4M | 0.1% | 2026-Q1 |
| VANGUARD GROUP INC added | 3,781,649 | $71M | 2.3% | 2025-Q4 stale |
| Nut Tree Capital Management, LP trimmed | 3,225,000 | $61M | 2.0% | 2025-Q4 stale |
| MACQUARIE GROUP LTD trimmed | 2,034,856 | $30M | 1.0% | 2025-Q3 stale |
| CAPSTONE INVESTMENT ADVISORS, LLC trimmed | 1,194,936 | $23M | 0.7% | 2025-Q4 stale |
| Empowered Funds, LLC added | 671,222 | $13M | 0.4% | 2025-Q4 stale |
| Thrivent Financial for Lutherans trimmed | 714,779 | $10M | 0.3% | 2025-Q2 stale |
| TUDOR INVESTMENT CORP ET AL trimmed | 496,715 | $9M | 0.3% | 2025-Q4 stale |
| WELLINGTON MANAGEMENT GROUP LLP added | 470,813 | $9M | 0.3% | 2025-Q4 stale |
| HOTCHKIS & WILEY CAPITAL MANAGEMENT LLC trimmed | 448,180 | $8M | 0.3% | 2025-Q4 stale |
| Woodline Partners LP new | 796,753 | $8M | 0.3% | 2025-Q1 stale |
| Cubist Systematic Strategies, LLC trimmed | 501,775 | $7M | 0.2% | 2025-Q3 stale |
| ADAGE CAPITAL PARTNERS GP, L.L.C. trimmed | 300,000 | $6M | 0.2% | 2025-Q4 stale |
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.