Who owns MRTN (MRTN)
Which tracked institutional funds hold MRTN, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See MRTN 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
59 tracked funds added or opened MRTN while 25 trimmed or exited it between 2025-Q4 and 2026-Q1 — 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
MRTN’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 MRTN more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in MRTN 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 224 tracked filers holding MRTN, 127 increased or opened the position and 87 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 MRTN 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 15
- VANGUARD CAPITAL MANAGEMENT LLC$33M
- VANGUARD PORTFOLIO MANAGEMENT LLC$15M
- NEXT CENTURY GROWTH INVESTORS LLC$5M
- VANGUARD FIDUCIARY TRUST CO$5M
- 4D Advisors, LLC$5M
- Stanley-Laman Group, Ltd.$4M
Full exits 9
- VANGUARD GROUP INC$41M
- GENEVA CAPITAL MANAGEMENT LLC$21M
- TWO SIGMA ADVISERS, LP$7M
- HOTCHKIS & WILEY CAPITAL MANAGEMENT LLC$3M
- AlphaQuest LLC$1M
- Forest Hill Capital, LLC$1M
Largest adds
- BlackRock, Inc.$18M
- FMR LLC$16M
- Boston Partners$12M
- ROYCE & ASSOCIATES LP$10M
- DIMENSIONAL FUND ADVISORS LP$9M
- TWO SIGMA INVESTMENTS, LP$9M
Largest trims
- NUANCE INVESTMENTS, LLC$8M
- BALYASNY ASSET MANAGEMENT L.P.$3M
- Point72 Asset Management, L.P.$3M
- Numerai GP LLC$2M
- UBS Group AG$2M
- Verition Fund Management LLC$2M
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. added | 9,760,018 | $128M | 14.9% | 2026-Q1 |
| DIMENSIONAL FUND ADVISORS LP added | 4,893,498 | $64M | 7.5% | 2026-Q1 |
| NUANCE INVESTMENTS, LLC trimmed | 4,810,420 | $63M | 7.3% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC added | 2,619,968 | $34M | 4.0% | 2026-Q1 |
| STATE STREET CORP added | 2,597,547 | $34M | 4.0% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 2,496,685 | $33M | 3.8% | 2026-Q1 |
| FMR LLC added | 1,754,717 | $23M | 2.7% | 2026-Q1 |
| Boston Partners added | 1,699,815 | $22M | 2.6% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 1,468,054 | $19M | 2.2% | 2026-Q1 |
| TWO SIGMA INVESTMENTS, LP added | 1,429,481 | $19M | 2.2% | 2026-Q1 |
| MORGAN STANLEY trimmed | 1,294,143 | $17M | 2.0% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 1,274,387 | $17M | 1.9% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 1,113,827 | $15M | 1.7% | 2026-Q1 |
| Russell Investments Group, Ltd. added | 1,097,390 | $14M | 1.7% | 2026-Q1 |
| ROYCE & ASSOCIATES LP added | 980,210 | $13M | 1.5% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC trimmed | 969,980 | $13M | 1.5% | 2026-Q1 |
| LONDON CO OF VIRGINIA added | 889,273 | $12M | 1.4% | 2026-Q1 |
| DEPRINCE RACE & ZOLLO INC added | 767,686 | $10M | 1.2% | 2026-Q1 |
| JPMORGAN CHASE & CO added | 769,161 | $10M | 1.1% | 2026-Q1 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 676,584 | $9M | 1.0% | 2026-Q1 |
| CITADEL ADVISORS LLC trimmed | 669,343 | $9M | 1.0% | 2026-Q1 |
| Nuveen, LLC trimmed | 651,516 | $9M | 1.0% | 2026-Q1 |
| NORTHERN TRUST CORP added | 626,320 | $8M | 1.0% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 620,134 | $8M | 0.9% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 557,096 | $7M | 0.8% | 2026-Q1 |
| TEACHER RETIREMENT SYSTEM OF TEXAS added | 546,810 | $7M | 0.8% | 2026-Q1 |
| NEXT CENTURY GROWTH INVESTORS LLC added | 418,371 | $5M | 0.6% | 2026-Q1 |
| Creative Planning added | 398,513 | $5M | 0.6% | 2026-Q1 |
| NICHOLAS COMPANY, INC. trimmed | 396,995 | $5M | 0.6% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 380,057 | $5M | 0.6% | 2026-Q1 |
| Invesco Ltd. trimmed | 360,221 | $5M | 0.5% | 2026-Q1 |
| HEARTLAND ADVISORS INC added | 350,000 | $5M | 0.5% | 2026-Q1 |
| 4D Advisors, LLC new | 350,000 | $5M | 0.5% | 2026-Q1 |
| AQR CAPITAL MANAGEMENT LLC added | 340,310 | $4M | 0.5% | 2026-Q1 |
| Bank of New York Mellon Corp trimmed | 321,717 | $4M | 0.5% | 2026-Q1 |
| ALLIANCEBERNSTEIN L.P. added | 358,019 | $4M | 0.5% | 2026-Q1 |
| FIRST TRUST ADVISORS LP added | 304,165 | $4M | 0.5% | 2026-Q1 |
| Mariner, LLC trimmed | 285,983 | $4M | 0.4% | 2026-Q1 |
| PRINCIPAL FINANCIAL GROUP INC added | 281,433 | $4M | 0.4% | 2026-Q1 |
| Stanley-Laman Group, Ltd. new | 272,469 | $4M | 0.4% | 2026-Q1 |
| US BANCORP \DE\ added | 268,758 | $4M | 0.4% | 2026-Q1 |
| Buckland Partners Management Co LLC | 267,594 | $4M | 0.4% | 2026-Q1 |
| SEI INVESTMENTS CO added | 220,314 | $3M | 0.3% | 2026-Q1 |
| Allianz Asset Management GmbH added | 219,129 | $3M | 0.3% | 2026-Q1 |
| Public Sector Pension Investment Board added | 207,075 | $3M | 0.3% | 2026-Q1 |
| Hudson Bay Capital Management LP added | 203,107 | $3M | 0.3% | 2026-Q1 |
| RHUMBLINE ADVISERS trimmed | 164,632 | $2M | 0.3% | 2026-Q1 |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC added | 159,568 | $2M | 0.2% | 2026-Q1 |
| Verition Fund Management LLC trimmed | 156,443 | $2M | 0.2% | 2026-Q1 |
| HRT FINANCIAL LP trimmed | 142,910 | $2M | 0.2% | 2026-Q1 |
| Legal & General Group Plc trimmed | 135,732 | $2M | 0.2% | 2026-Q1 |
| RAYMOND JAMES FINANCIAL INC added | 128,627 | $2M | 0.2% | 2026-Q1 |
| UBS Group AG trimmed | 120,661 | $2M | 0.2% | 2026-Q1 |
| Swiss National Bank | 120,575 | $2M | 0.2% | 2026-Q1 |
| WINTON GROUP Ltd trimmed | 112,010 | $1M | 0.2% | 2026-Q1 |
| CastleKnight Management LP new | 108,400 | $1M | 0.2% | 2026-Q1 |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND | 92,164 | $1M | 0.1% | 2026-Q1 |
| Numerai GP LLC trimmed | 88,533 | $1M | 0.1% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 82,844 | $1M | 0.1% | 2026-Q1 |
| BARCLAYS PLC trimmed | 80,741 | $1M | 0.1% | 2026-Q1 |
| SG Americas Securities, LLC trimmed | 80,662 | $1M | 0.1% | 2026-Q1 |
| CONFLUENCE INVESTMENT MANAGEMENT LLC trimmed | 80,613 | $1M | 0.1% | 2026-Q1 |
| HSBC HOLDINGS PLC added | 79,083 | $1M | 0.1% | 2026-Q1 |
| Trexquant Investment LP added | 74,510 | $978K | 0.1% | 2026-Q1 |
| Ausbil Investment Management Ltd added | 72,299 | $967K | 0.1% | 2026-Q1 |
| Canvas Wealth Advisors, LLC trimmed | 73,615 | $967K | 0.1% | 2026-Q1 |
| MARTINGALE ASSET MANAGEMENT L P added | 63,800 | $838K | 0.1% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 62,803 | $825K | 0.1% | 2026-Q1 |
| Quantinno Capital Management LP added | 61,545 | $808K | 0.1% | 2026-Q1 |
| JANE STREET GROUP, LLC added | 60,648 | $796K | 0.1% | 2026-Q1 |
| PRUDENTIAL FINANCIAL INC added | 59,943 | $787K | 0.1% | 2026-Q1 |
| DEUTSCHE BANK AG\ added | 56,391 | $740K | 0.1% | 2026-Q1 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed | 55,778 | $732K | 0.1% | 2026-Q1 |
| CITIGROUP INC added | 54,959 | $722K | 0.1% | 2026-Q1 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP added | 49,810 | $654K | 0.1% | 2026-Q1 |
| CANADA LIFE ASSURANCE Co | 49,556 | $651K | 0.1% | 2026-Q1 |
| VANGUARD GROUP INC trimmed | 3,567,670 | $41M | 4.7% | 2025-Q4 stale |
| GENEVA CAPITAL MANAGEMENT LLC trimmed | 1,868,567 | $21M | 2.5% | 2025-Q4 stale |
| WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC trimmed | 1,320,316 | $17M | 2.0% | 2025-Q2 stale |
| TWO SIGMA ADVISERS, LP added | 601,116 | $7M | 0.8% | 2025-Q4 stale |
| RENAISSANCE TECHNOLOGIES LLC added | 516,897 | $6M | 0.6% | 2025-Q3 stale |
| Clearbridge Investments, LLC added | 463,768 | $5M | 0.6% | 2025-Q3 stale |
| Cubist Systematic Strategies, LLC added | 323,901 | $3M | 0.4% | 2025-Q3 stale |
| HOTCHKIS & WILEY CAPITAL MANAGEMENT LLC added | 288,702 | $3M | 0.4% | 2025-Q4 stale |
| WOLVERINE TRADING, LLC added | 234,483 | $3M | 0.4% | 2025-Q2 stale |
| Empirical Capital Management, LLC trimmed | 200,000 | $3M | 0.3% | 2025-Q1 stale |
| NORGES BANK added | 135,900 | $2M | 0.3% | 2025-Q3 stale |
| Hodges Capital Management Inc. added | 166,100 | $2M | 0.3% | 2025-Q2 stale |
| Van Hulzen Asset Management, LLC trimmed | 116,836 | $2M | 0.2% | 2025-Q1 stale |
| AlphaQuest LLC added | 121,536 | $1M | 0.2% | 2025-Q4 stale |
| Forest Hill Capital, LLC added | 115,000 | $1M | 0.2% | 2025-Q4 stale |
| Penn Capital Management Company, LLC trimmed | 99,253 | $1M | 0.1% | 2025-Q2 stale |
| Qube Research & Technologies Ltd trimmed | 102,484 | $1M | 0.1% | 2025-Q4 stale |
| JACOBS LEVY EQUITY MANAGEMENT, INC trimmed | 106,760 | $1M | 0.1% | 2025-Q3 stale |
| Y-Intercept (Hong Kong) Ltd trimmed | 85,174 | $969K | 0.1% | 2025-Q4 stale |
| Dynamic Technology Lab Private Ltd added | 72,780 | $945K | 0.1% | 2025-Q2 stale |
| TECTONIC ADVISORS LLC added | 69,205 | $899K | 0.1% | 2025-Q2 stale |
| Nebula Research & Development LLC trimmed | 65,630 | $853K | 0.1% | 2025-Q2 stale |
| Jump Financial, LLC trimmed | 71,968 | $819K | 0.1% | 2025-Q4 stale |
| WEALTHEDGE INVESTMENT ADVISORS, LLC added | 71,707 | $764K | 0.1% | 2025-Q3 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.