Who owns GSM
Which tracked institutional funds hold GSM, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See GSM company fundamentals →
Ownership as of the 2026-Q1 13F filings (latest filed 2026-05-18). 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 GSM is one-sided between 2025-Q4 and 2026-Q1: 18 added or opened and 55 trimmed or exited — on balance reducing.
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
GSM’s largest tracked holder by dollar value, COOPER CREEK PARTNERS MANAGEMENT LLC, sizes it at 2.7% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 2.7pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in GSM 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 173 tracked filers holding GSM, 79 increased or opened the position and 86 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 GSM 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 9
- MILLENNIUM MANAGEMENT LLC$4M
- Bastion Asset Management Inc.$4M
- VANGUARD PORTFOLIO MANAGEMENT LLC$3M
- ExodusPoint Capital Management, LP$2M
- MASSACHUSETTS FINANCIAL SERVICES CO /MA/$830K
- MARTINGALE ASSET MANAGEMENT L P$816K
Full exits 7
- ARDSLEY ADVISORY PARTNERS LP$10M
- VANGUARD GROUP INC$4M
- WEXFORD CAPITAL LP$2M
- JANE STREET GROUP, LLC$936K
- Orion Resource Partners LP$858K
- Verition Fund Management LLC$706K
Largest adds
- GENDELL JEFFREY L$3M
- Universal- Beteiligungs- und Servicegesellschaft mbH$2M
- HRT FINANCIAL LP$1M
- Jump Financial, LLC$911K
- SEI INVESTMENTS CO$857K
- JACOBS LEVY EQUITY MANAGEMENT, INC$353K
Largest trims
- GOLDMAN SACHS GROUP INC$20M
- COOPER CREEK PARTNERS MANAGEMENT LLC$13M
- BARROW HANLEY MEWHINNEY & STRAUSS LLC$5M
- BlackRock, Inc.$4M
- Hosking Partners LLP$4M
- GRIZZLYROCK CAPITAL, LLC$4M
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 |
|---|---|---|---|---|
| COOPER CREEK PARTNERS MANAGEMENT LLC trimmed | 13,715,302 | $57M | 12.2% | 2026-Q1 |
| Hosking Partners LLP added | 11,561,188 | $48M | 10.3% | 2026-Q1 |
| BlackRock, Inc. trimmed | 6,652,203 | $27M | 5.9% | 2026-Q1 |
| BARROW HANLEY MEWHINNEY & STRAUSS LLC trimmed | 6,075,049 | $25M | 5.4% | 2026-Q1 |
| DONALD SMITH & CO., INC. added | 5,434,704 | $22M | 4.8% | 2026-Q1 |
| Old West Investment Management, LLC added | 3,926,619 | $16M | 3.5% | 2026-Q1 |
| GRIZZLYROCK CAPITAL, LLC trimmed | 3,628,840 | $15M | 3.2% | 2026-Q1 |
| RENAISSANCE TECHNOLOGIES LLC trimmed | 2,768,235 | $11M | 2.5% | 2026-Q1 |
| ROYCE & ASSOCIATES LP trimmed | 2,348,451 | $10M | 2.1% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC trimmed | 2,216,942 | $9M | 2.0% | 2026-Q1 |
| DIMENSIONAL FUND ADVISORS LP trimmed | 2,206,383 | $9M | 2.0% | 2026-Q1 |
| First Eagle Investment Management, LLC added | 2,083,272 | $9M | 1.9% | 2026-Q1 |
| STATE STREET CORP added | 2,079,718 | $9M | 1.9% | 2026-Q1 |
| MASTERS CAPITAL MANAGEMENT LLC | 2,000,000 | $8M | 1.8% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC trimmed | 1,790,180 | $7M | 1.6% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 1,592,749 | $7M | 1.4% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC trimmed | 1,475,448 | $6M | 1.3% | 2026-Q1 |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC added | 1,415,337 | $6M | 1.3% | 2026-Q1 |
| JACOBS LEVY EQUITY MANAGEMENT, INC added | 1,303,260 | $5M | 1.2% | 2026-Q1 |
| Man Investment Partners (US) LP trimmed | 1,286,367 | $5M | 1.1% | 2026-Q1 |
| Russell Investments Group, Ltd. trimmed | 1,209,493 | $5M | 1.1% | 2026-Q1 |
| Walleye Capital LLC trimmed | 1,185,259 | $5M | 1.1% | 2026-Q1 |
| Thomist Capital Management, LP trimmed | 1,083,764 | $4M | 1.0% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC added | 1,039,411 | $4M | 0.9% | 2026-Q1 |
| Bastion Asset Management Inc. new | 909,547 | $4M | 0.9% | 2026-Q1 |
| CenterBook Partners LP trimmed | 935,523 | $4M | 0.8% | 2026-Q1 |
| GENDELL JEFFREY L added | 912,323 | $4M | 0.8% | 2026-Q1 |
| GENERAL AMERICAN INVESTORS CO INC trimmed | 907,591 | $4M | 0.8% | 2026-Q1 |
| Empowered Funds, LLC added | 879,237 | $4M | 0.8% | 2026-Q1 |
| Ballast Asset Management, LP added | 870,172 | $4M | 0.8% | 2026-Q1 |
| Wolf Hill Capital Management, LP trimmed | 855,685 | $4M | 0.8% | 2026-Q1 |
| CITADEL ADVISORS LLC trimmed | 711,452 | $3M | 0.6% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 687,228 | $3M | 0.6% | 2026-Q1 |
| Orchard Capital Management, LLC | 681,745 | $3M | 0.6% | 2026-Q1 |
| NORTHERN TRUST CORP added | 672,020 | $3M | 0.6% | 2026-Q1 |
| Universal- Beteiligungs- und Servicegesellschaft mbH added | 668,757 | $3M | 0.6% | 2026-Q1 |
| JB CAPITAL PARTNERS LP | 655,000 | $3M | 0.6% | 2026-Q1 |
| HRT FINANCIAL LP added | 650,087 | $3M | 0.6% | 2026-Q1 |
| SEI INVESTMENTS CO added | 639,440 | $3M | 0.6% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC trimmed | 576,638 | $2M | 0.5% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ trimmed | 561,001 | $2M | 0.5% | 2026-Q1 |
| RBF Capital, LLC | 521,005 | $2M | 0.5% | 2026-Q1 |
| 1492 Capital Management LLC added | 519,449 | $2M | 0.5% | 2026-Q1 |
| ENVESTNET ASSET MANAGEMENT INC added | 491,209 | $2M | 0.4% | 2026-Q1 |
| DBA TRADING, LLC trimmed | 460,000 | $2M | 0.4% | 2026-Q1 |
| JPMORGAN CHASE & CO trimmed | 450,497 | $2M | 0.4% | 2026-Q1 |
| ExodusPoint Capital Management, LP added | 417,413 | $2M | 0.4% | 2026-Q1 |
| Boston Partners trimmed | 351,435 | $1M | 0.3% | 2026-Q1 |
| Jump Financial, LLC added | 349,834 | $1M | 0.3% | 2026-Q1 |
| UBS Group AG trimmed | 337,777 | $1M | 0.3% | 2026-Q1 |
| Pekin Hardy Strauss, Inc. | 325,400 | $1M | 0.3% | 2026-Q1 |
| Invesco Ltd. added | 300,448 | $1M | 0.3% | 2026-Q1 |
| Bank of New York Mellon Corp trimmed | 254,591 | $1M | 0.2% | 2026-Q1 |
| MORGAN STANLEY trimmed | 245,380 | $1M | 0.2% | 2026-Q1 |
| BANK OF MONTREAL /CAN/ added | 244,145 | $1M | 0.2% | 2026-Q1 |
| LPL Financial LLC added | 235,872 | $972K | 0.2% | 2026-Q1 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP trimmed | 227,150 | $936K | 0.2% | 2026-Q1 |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ trimmed | 201,546 | $830K | 0.2% | 2026-Q1 |
| MARTINGALE ASSET MANAGEMENT L P new | 198,107 | $816K | 0.2% | 2026-Q1 |
| Counterpoint Mutual Funds LLC added | 192,189 | $792K | 0.2% | 2026-Q1 |
| Nuveen, LLC | 174,473 | $719K | 0.2% | 2026-Q1 |
| Verdence Capital Advisors LLC new | 160,171 | $660K | 0.1% | 2026-Q1 |
| PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO added | 157,461 | $649K | 0.1% | 2026-Q1 |
| D. E. Shaw & Co., Inc. added | 156,576 | $645K | 0.1% | 2026-Q1 |
| Unison Advisors LLC | 156,142 | $643K | 0.1% | 2026-Q1 |
| RHUMBLINE ADVISERS trimmed | 147,018 | $606K | 0.1% | 2026-Q1 |
| ACADIAN ASSET MANAGEMENT LLC trimmed | 141,696 | $581K | 0.1% | 2026-Q1 |
| Legal & General Group Plc trimmed | 137,323 | $566K | 0.1% | 2026-Q1 |
| ALGERT GLOBAL LLC new | 126,718 | $522K | 0.1% | 2026-Q1 |
| Caption Management, LLC trimmed | 126,115 | $520K | 0.1% | 2026-Q1 |
| West Tower Group, LLC | 125,285 | $516K | 0.1% | 2026-Q1 |
| DEUTSCHE BANK AG\ trimmed | 120,764 | $498K | 0.1% | 2026-Q1 |
| ALLIANCEBERNSTEIN L.P. | 100,200 | $465K | 0.1% | 2026-Q1 |
| Susquehanna Portfolio Strategies, LLC trimmed | 112,267 | $463K | 0.1% | 2026-Q1 |
| Diametric Capital, LP trimmed | 108,869 | $449K | 0.1% | 2026-Q1 |
| Connor, Clark & Lunn Investment Management Ltd. trimmed | 105,863 | $436K | 0.1% | 2026-Q1 |
| LOS ANGELES CAPITAL MANAGEMENT LLC added | 102,170 | $421K | 0.1% | 2026-Q1 |
| Quantbot Technologies LP added | 100,560 | $414K | 0.1% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 93,280 | $385K | 0.1% | 2026-Q1 |
| MARSHALL WACE, LLP added | 91,283 | $376K | 0.1% | 2026-Q1 |
| STRS OHIO | 81,600 | $336K | 0.1% | 2026-Q1 |
| Aquatic Capital Management LLC added | 80,178 | $330K | 0.1% | 2026-Q1 |
| ARDSLEY ADVISORY PARTNERS LP added | 2,120,000 | $10M | 2.1% | 2025-Q4 stale |
| BARDIN HILL MANAGEMENT PARTNERS LP | 1,752,967 | $8M | 1.7% | 2025-Q3 stale |
| AYAL Capital Advisors Ltd trimmed | 1,075,400 | $5M | 1.1% | 2025-Q3 stale |
| VANGUARD GROUP INC added | 814,826 | $4M | 0.8% | 2025-Q4 stale |
| DEPRINCE RACE & ZOLLO INC trimmed | 732,166 | $3M | 0.7% | 2025-Q3 stale |
| Graham Capital Management, L.P. trimmed | 735,300 | $3M | 0.6% | 2025-Q2 stale |
| MOORE CAPITAL MANAGEMENT, LP new | 411,264 | $2M | 0.4% | 2025-Q3 stale |
| WEXFORD CAPITAL LP | 345,508 | $2M | 0.3% | 2025-Q4 stale |
| JANE STREET GROUP, LLC trimmed | 201,725 | $936K | 0.2% | 2025-Q4 stale |
| Arena Capital Advisors, LLC- CA trimmed | 200,000 | $910K | 0.2% | 2025-Q3 stale |
| Orion Resource Partners LP new | 184,883 | $858K | 0.2% | 2025-Q4 stale |
| Trexquant Investment LP trimmed | 204,207 | $758K | 0.2% | 2025-Q1 stale |
| Verition Fund Management LLC trimmed | 152,076 | $706K | 0.2% | 2025-Q4 stale |
| SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC trimmed | 171,799 | $631K | 0.1% | 2025-Q2 stale |
| Lombard Odier Asset Management (USA) Corp trimmed | 118,457 | $550K | 0.1% | 2025-Q4 stale |
| SummerHaven Investment Management, LLC added | 140,675 | $516K | 0.1% | 2025-Q2 stale |
| Maven Securities LTD added | 107,228 | $398K | 0.1% | 2025-Q1 stale |
| Point72 Asset Management, L.P. added | 84,646 | $393K | 0.1% | 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.