Who owns Marten Transport (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-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
68 tracked funds added or opened MRTN while 26 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
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 2026-Q1 and 2026-Q2, across 214 tracked filers holding MRTN, 116 increased or opened the position and 111 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 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 11
- CRAMER ROSENTHAL MCGLYNN LLC$26M
- 12th Street Asset Management Company, LLC$13M
- NORGES BANK$7M
- MACKENZIE FINANCIAL CORP$5M
- Polar Asset Management Partners Inc.$4M
- Aptus Capital Advisors, LLC$4M
Full exits 12
- 4D Advisors, LLC$5M
- VOLORIDGE INVESTMENT MANAGEMENT, LLC$2M
- HRT FINANCIAL LP$2M
- Numerai GP LLC$1M
- SG Americas Securities, LLC$1M
- JANE STREET GROUP, LLC$796K
Largest adds
- BlackRock, Inc.$46M
- GOLDMAN SACHS GROUP INC$28M
- Nuveen, LLC$25M
- FMR LLC$24M
- DIMENSIONAL FUND ADVISORS LP$22M
- AMERICAN CENTURY COMPANIES INC$14M
Largest trims
- NUANCE INVESTMENTS, LLC$54M
- Boston Partners$4M
- FIRST TRUST ADVISORS LP$4M
- ALLIANCEBERNSTEIN L.P.$3M
- Mariner, LLC$2M
- RAYMOND JAMES FINANCIAL INC$1M
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 | 10,058,930 | $175M | 17.0% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP added | 4,999,156 | $87M | 8.5% | 2026-Q2 |
| AMERICAN CENTURY COMPANIES INC added | 2,800,863 | $49M | 4.7% | 2026-Q2 |
| STATE STREET CORP added | 2,723,602 | $47M | 4.6% | 2026-Q2 |
| FMR LLC added | 2,702,378 | $47M | 4.6% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 2,524,859 | $44M | 4.3% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC added | 2,101,794 | $36M | 3.6% | 2026-Q2 |
| Nuveen, LLC added | 1,945,243 | $34M | 3.3% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 1,830,565 | $32M | 3.1% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 1,554,058 | $27M | 2.6% | 2026-Q2 |
| CRAMER ROSENTHAL MCGLYNN LLC new | 1,523,757 | $26M | 2.6% | 2026-Q2 |
| ROYCE & ASSOCIATES LP added | 1,394,890 | $24M | 2.4% | 2026-Q2 |
| MORGAN STANLEY added | 1,353,069 | $23M | 2.3% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC added | 1,218,980 | $21M | 2.1% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC trimmed | 1,198,050 | $21M | 2.0% | 2026-Q2 |
| AMERIPRISE FINANCIAL INC added | 1,081,606 | $19M | 1.8% | 2026-Q2 |
| Boston Partners trimmed | 1,049,147 | $18M | 1.8% | 2026-Q2 |
| Russell Investments Group, Ltd. trimmed | 922,443 | $16M | 1.6% | 2026-Q2 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 919,740 | $16M | 1.6% | 2026-Q2 |
| LONDON CO OF VIRGINIA trimmed | 853,969 | $15M | 1.4% | 2026-Q2 |
| 12th Street Asset Management Company, LLC new | 758,634 | $13M | 1.3% | 2026-Q2 |
| DEPRINCE RACE & ZOLLO INC trimmed | 742,362 | $13M | 1.3% | 2026-Q2 |
| CITADEL ADVISORS LLC added | 722,251 | $13M | 1.2% | 2026-Q2 |
| NEXT CENTURY GROWTH INVESTORS LLC added | 699,305 | $12M | 1.2% | 2026-Q2 |
| NORTHERN TRUST CORP added | 667,681 | $12M | 1.1% | 2026-Q2 |
| JPMORGAN CHASE & CO trimmed | 604,366 | $11M | 1.0% | 2026-Q2 |
| NUANCE INVESTMENTS, LLC trimmed | 546,871 | $9M | 0.9% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ trimmed | 486,041 | $8M | 0.8% | 2026-Q2 |
| Creative Planning added | 419,369 | $7M | 0.7% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 395,125 | $7M | 0.7% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO added | 384,638 | $7M | 0.7% | 2026-Q2 |
| NORGES BANK added | 379,000 | $7M | 0.6% | 2026-Q2 |
| TEACHER RETIREMENT SYSTEM OF TEXAS trimmed | 363,027 | $6M | 0.6% | 2026-Q2 |
| HEARTLAND ADVISORS INC | 350,000 | $6M | 0.6% | 2026-Q2 |
| Bank of New York Mellon Corp added | 329,668 | $6M | 0.6% | 2026-Q2 |
| Invesco Ltd. trimmed | 323,199 | $6M | 0.5% | 2026-Q2 |
| NICHOLAS COMPANY, INC. trimmed | 315,135 | $5M | 0.5% | 2026-Q2 |
| MACKENZIE FINANCIAL CORP added | 313,098 | $5M | 0.5% | 2026-Q2 |
| PRINCIPAL FINANCIAL GROUP INC trimmed | 279,992 | $5M | 0.5% | 2026-Q2 |
| Stanley-Laman Group, Ltd. trimmed | 270,445 | $5M | 0.5% | 2026-Q2 |
| Buckland Partners Management Co LLC | 267,594 | $5M | 0.5% | 2026-Q2 |
| Polar Asset Management Partners Inc. new | 255,800 | $4M | 0.4% | 2026-Q2 |
| UBS Group AG added | 250,880 | $4M | 0.4% | 2026-Q2 |
| Allianz Asset Management GmbH added | 241,291 | $4M | 0.4% | 2026-Q2 |
| Aptus Capital Advisors, LLC new | 204,337 | $4M | 0.3% | 2026-Q2 |
| US BANCORP \DE\ trimmed | 200,518 | $3M | 0.3% | 2026-Q2 |
| Public Sector Pension Investment Board trimmed | 198,609 | $3M | 0.3% | 2026-Q2 |
| RHUMBLINE ADVISERS trimmed | 146,904 | $3M | 0.2% | 2026-Q2 |
| Legal & General Group Plc trimmed | 132,866 | $2M | 0.2% | 2026-Q2 |
| Connor, Clark & Lunn Investment Management Ltd. added | 125,451 | $2M | 0.2% | 2026-Q2 |
| Verition Fund Management LLC trimmed | 123,943 | $2M | 0.2% | 2026-Q2 |
| Campbell & CO Investment Adviser LLC added | 121,003 | $2M | 0.2% | 2026-Q2 |
| SEI INVESTMENTS CO trimmed | 120,557 | $2M | 0.2% | 2026-Q2 |
| Swiss National Bank trimmed | 114,475 | $2M | 0.2% | 2026-Q2 |
| CastleKnight Management LP | 108,400 | $2M | 0.2% | 2026-Q2 |
| Mariner, LLC trimmed | 107,420 | $2M | 0.2% | 2026-Q2 |
| Hudson Bay Capital Management LP trimmed | 106,780 | $2M | 0.2% | 2026-Q2 |
| WINTON GROUP Ltd trimmed | 92,430 | $2M | 0.2% | 2026-Q2 |
| Fulcrum Asset Management LLP new | 85,530 | $2M | 0.1% | 2026-Q2 |
| CITIGROUP INC added | 79,931 | $1M | 0.1% | 2026-Q2 |
| Atria Investments, Inc new | 77,005 | $1M | 0.1% | 2026-Q2 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC trimmed | 76,867 | $1M | 0.1% | 2026-Q2 |
| CONFLUENCE INVESTMENT MANAGEMENT LLC trimmed | 75,256 | $1M | 0.1% | 2026-Q2 |
| Quantinno Capital Management LP added | 75,197 | $1M | 0.1% | 2026-Q2 |
| XTX Topco Ltd added | 73,829 | $1M | 0.1% | 2026-Q2 |
| BARCLAYS PLC trimmed | 72,525 | $1M | 0.1% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 66,942 | $1M | 0.1% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. trimmed | 64,783 | $851K | 0.1% | 2026-Q2 |
| DEUTSCHE BANK AG\ added | 62,893 | $1M | 0.1% | 2026-Q2 |
| MARTINGALE ASSET MANAGEMENT L P trimmed | 61,900 | $1M | 0.1% | 2026-Q2 |
| PRUDENTIAL FINANCIAL INC added | 60,673 | $1M | 0.1% | 2026-Q2 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM added | 58,980 | $1M | 0.1% | 2026-Q2 |
| ENVESTNET ASSET MANAGEMENT INC added | 56,449 | $979K | 0.1% | 2026-Q2 |
| Ausbil Investment Management Ltd trimmed | 56,438 | $985K | 0.1% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC added | 55,424 | $962K | 0.1% | 2026-Q2 |
| EntryPoint Capital, LLC added | 54,331 | $943K | 0.1% | 2026-Q2 |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND trimmed | 53,716 | $932K | 0.1% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN added | 51,089 | $886K | 0.1% | 2026-Q2 |
| PDT Partners, LLC | 47,063 | $817K | 0.1% | 2026-Q2 |
| Horizon Investments, LLC new | 46,453 | $806K | 0.1% | 2026-Q2 |
| VANGUARD ASSET MANAGEMENT, Ltd | 44,464 | $771K | 0.1% | 2026-Q2 |
| MERCER GLOBAL ADVISORS INC /ADV added | 44,151 | $766K | 0.1% | 2026-Q2 |
| HSBC HOLDINGS PLC trimmed | 43,719 | $761K | 0.1% | 2026-Q2 |
| FRANKLIN RESOURCES INC added | 43,439 | $754K | 0.1% | 2026-Q2 |
| Vanguard Personalized Indexing Management, LLC trimmed | 40,477 | $702K | 0.1% | 2026-Q2 |
| Inspire Investing, LLC trimmed | 39,035 | $677K | 0.1% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS added | 35,756 | $620K | 0.1% | 2026-Q2 |
| MetLife Investment Management, LLC added | 34,991 | $607K | 0.1% | 2026-Q2 |
| Simplicity Wealth,LLC new | 32,657 | $567K | 0.1% | 2026-Q2 |
| Illinois Municipal Retirement Fund trimmed | 30,133 | $523K | 0.1% | 2026-Q2 |
| DARK FOREST CAPITAL MANAGEMENT LP added | 29,300 | $508K | 0.0% | 2026-Q2 |
| Jupiter Topco LLC new | 28,133 | $489K | 0.0% | 2026-Q2 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. trimmed | 27,323 | $474K | 0.0% | 2026-Q2 |
| Cetera Investment Advisers added | 27,292 | $474K | 0.0% | 2026-Q2 |
| CANADA PENSION PLAN INVESTMENT BOARD | 27,000 | $468K | 0.0% | 2026-Q2 |
| STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM added | 26,741 | $464K | 0.0% | 2026-Q2 |
| Graham Capital Management, L.P. added | 25,010 | $434K | 0.0% | 2026-Q2 |
| ELEVATION POINT WEALTH PARTNERS, LLC added | 24,738 | $429K | 0.0% | 2026-Q2 |
| NEUBERGER BERMAN GROUP LLC added | 23,671 | $411K | 0.0% | 2026-Q2 |
| BLAIR WILLIAM & CO/IL added | 23,158 | $402K | 0.0% | 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.