The public view is the crawlable proof. The same sourced dataset is available through REST and MCP for agents, research scripts, and back-office tools.
This stock page is the Follow view. The Build view lets your agent query MRTN owners, fund changes, insider filings, and source links through REST or MCP.
curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/stocks/MRTN"
Use Arkolith to show who owns MRTN, which funds added or reduced it, and which SEC filings prove each claim.
| # | Fund | Position value | Shares | Last move | As of | History |
|---|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | $128.1M | 9.8M | ▲+0.9% Added · +91K sh | Q1 2026 | |
| 2 | VANGUARD GROUP INC | $45.7M | 4.0M | ▼−5.4% Reduced · −228K sh | Q4 2025 | |
| 3 | STATE STREET CORP | $34.1M | 2.6M | ▲+6.3% Added · +155K sh | Q1 2026 | |
| 4 | FMR LLC | $23.2M | 1.8M | ▲+168% Added · +1.1M sh | Q1 2026 | |
| 5 | GEODE CAPITAL MANAGEMENT, LLC | $19.3M | 1.5M | ▲+2.4% Added · +35K sh | Q1 2026 | |
| 6 | VANGUARD PORTFOLIO MANAGEMENT LLC | $14.6M | 1.1M | ▲New +1.1M sh | Q1 2026 | |
| 7 | LONDON CO OF VIRGINIA | $11.7M | 889K | ▲+5.8% Added · +49K sh | Q1 2026 | |
| 8 | DEPRINCE RACE & ZOLLO INC | $10.1M | 768K | ▲+11% Added · +74K sh | Q1 2026 | |
| 9 | CITADEL ADVISORS LLC | $8.8M | 669K | ▼−4.5% Reduced · −32K sh | Q1 2026 | |
| 10 | TEACHER RETIREMENT SYSTEM OF TEXAS | $7.2M | 547K | ▲+12% Added · +59K sh | Q1 2026 | |
| 11 | NICHOLAS COMPANY, INC. | $5.2M | 397K | ▼−0.4% Reduced · −2K sh | Q1 2026 | |
| 12 | VANGUARD FIDUCIARY TRUST CO | $5.0M | 380K | ▲New +380K sh | Q1 2026 | |
| 13 | HEARTLAND ADVISORS INC | $4.6M | 350K | ▲+17% Added · +50K sh | Q1 2026 | |
| 14 | PUBLIC SECTOR PENSION INVESTMENT BOARD | $2.7M | 207K | ▲+3.3% Added · +7K sh | Q1 2026 | |
| 15 | Hudson Bay Capital Management LP | $2.7M | 203K | ▲+56% Added · +73K sh | Q1 2026 | |
| 16 | VOLORIDGE INVESTMENT MANAGEMENT, LLC | $2.1M | 160K | ▲New +160K sh | Q1 2026 | |
| 17 | Verition Fund Management LLC | $2.1M | 156K | ▼−54% Reduced · −180K sh | Q1 2026 | |
| 18 | WINTON GROUP Ltd | $1.5M | 112K | ▼−0.3% Reduced · −359 sh | Q1 2026 | |
| 19 | CastleKnight Management LP | $1.4M | 108K | ▲New +108K sh | Q1 2026 | |
| 20 | Trexquant Investment LP | $978K | 75K | ▲New +75K sh | Q1 2026 | |
| 21 | Vanguard Personalized Indexing Management, LLC | $558K | 42K | ▲+16% Added · +6K sh | Q1 2026 | |
| 22 | Point72 Asset Management, L.P. | $469K | 36K | ▼−87% Reduced · −232K sh | Q1 2026 | |
| 23 | Illinois Municipal Retirement Fund | $441K | 34K | ▲+23% Added · +6K sh | Q1 2026 | |
| 24 | Connor, Clark & Lunn Investment Management Ltd. | $434K | 33K | ▲New +33K sh | Q1 2026 | |
| 25 | Centiva Capital, LP | $398K | 30K | ▲+134% Added · +17K sh | Q1 2026 |
Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.
| Date | Insider | Role | Action | Shares | Value |
|---|---|---|---|---|---|
| Feb 20, 2026 | MARTEN RANDOLPH L | Chairman of the Board and CEO, Director, 10% Owner | Tax withholding (F) | 5K | $65K |
| Feb 20, 2026 | Petit Douglas Paul | President | Tax withholding (F) | 2K | $32K |
| Feb 20, 2026 | Baier Randall John | Exec. VP & Chief Tech. Officer | Tax withholding (F) | 1K | $18K |
| Feb 20, 2026 | Phillips Adam Daniel | EVP & Chief Operating Officer | Tax withholding (F) | 1K | $16K |
| Feb 20, 2026 | Hinnendael James J | Exec. VP and CFO | Tax withholding (F) | 3K | $40K |
| Dec 24, 2025 | DEMOREST ROBERT L | Director | Gift (G) | 7K | $0 |
| Aug 19, 2025 | MARTEN RANDOLPH L | Executive Chairman of Board, Director, 10% Owner | Gift (G) | 2K | $0 |
| May 6, 2025 | Jones Patricia L | Director | Grant (A) | 5K | $0 |
| May 6, 2025 | IVERSON KATHLEEN P | Director | Grant (A) | 5K | $0 |
| May 6, 2025 | DEMOREST ROBERT L | Director | Grant (A) | 5K | $0 |
| May 6, 2025 | BAUER JERRY M | Director | Grant (A) | 5K | $0 |
| May 6, 2025 | HAGNESS LARRY B | Director | Grant (A) | 5K | $0 |
| Company | Co-held by | Combined value |
|---|---|---|
| MICROSOFT CORPMSFT | 59 funds | $24.7B |
| AMAZON.COM INCAMZN | 56 funds | $19.7B |
| ALPHABET INC-CL AGOOGL | 56 funds | $17.0B |
| UNITEDHEALTH GROUP INCUNH | 56 funds | $3.0B |
| NVIDIA CORPNVDA | 55 funds | $35.0B |
| COSTCO WHOLESALE CORPCOST | 55 funds | $5.2B |
| O'REILLY AUTOMOTIVE INCORLY | 55 funds | $2.0B |
| APPLE INCAAPL | 54 funds | $29.0B |
| BROADCOM INCAVGO | 54 funds | $12.6B |
| ELI LILLY & COLLY | 54 funds | $6.6B |
| VISA INC-CLASS A SHARESV | 54 funds | $5.9B |
| FEDEX CORPFDX | 54 funds | $2.0B |
Ranked by how many of MRTN's institutional holders also hold each name, a cross-fund conviction signal. Via the MCP server (ticker.co_held).
13F holdings + Form 4 insider transactions + end-of-day price history + the live filing stream, joined for MRTN. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes. Every panel above is one call to the Arkolith API & MCP server.