Who owns MLAB (MLAB)
Which tracked institutional funds hold MLAB, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See MLAB 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
47 tracked funds added or opened MLAB while 23 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
MLAB’s largest tracked holder by dollar value, Long Path Partners LP, sizes it at 16.3% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 16.3pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in MLAB 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 159 tracked filers holding MLAB, 85 increased or opened the position and 68 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 MLAB 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 10
- VANGUARD CAPITAL MANAGEMENT LLC$21M
- VANGUARD PORTFOLIO MANAGEMENT LLC$5M
- WASATCH ADVISORS LP$5M
- VANGUARD FIDUCIARY TRUST CO$3M
- LAZARD ASSET MANAGEMENT LLC$2M
- CenterBook Partners LP$1M
Full exits 9
- VANGUARD GROUP INC$25M
- GENEVA CAPITAL MANAGEMENT LLC$14M
- MASON CAPITAL MANAGEMENT LLC$6M
- JANE STREET GROUP, LLC$4M
- Qube Research & Technologies Ltd$2M
- Irenic Capital Management LP$2M
Largest adds
- Long Path Partners LP$18M
- AQR CAPITAL MANAGEMENT LLC$9M
- Boston Partners$7M
- MONIMUS CAPITAL MANAGEMENT, LP$6M
- Select Equity Group, L.P.$5M
- BlackRock, Inc.$4M
Largest trims
- CITADEL ADVISORS LLC$4M
- JANUS HENDERSON GROUP PLC$3M
- Trexquant Investment LP$2M
- TUDOR INVESTMENT CORP ET AL$2M
- D. E. Shaw & Co., Inc.$1M
- Man Group plc$832K
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 |
|---|---|---|---|---|
| Long Path Partners LP added | 405,583 | $36M | 6.4% | 2026-Q1 |
| BlackRock, Inc. trimmed | 393,851 | $35M | 6.2% | 2026-Q1 |
| Boston Partners added | 268,711 | $24M | 4.3% | 2026-Q1 |
| Select Equity Group, L.P. added | 235,885 | $21M | 3.7% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 232,643 | $21M | 3.7% | 2026-Q1 |
| Ranger Investment Management, L.P. trimmed | 202,903 | $18M | 3.2% | 2026-Q1 |
| AQR CAPITAL MANAGEMENT LLC added | 168,986 | $15M | 2.7% | 2026-Q1 |
| MORGAN STANLEY trimmed | 162,116 | $14M | 2.6% | 2026-Q1 |
| ROYCE & ASSOCIATES LP added | 161,229 | $14M | 2.6% | 2026-Q1 |
| DIAMOND HILL CAPITAL MANAGEMENT INC added | 155,302 | $14M | 2.5% | 2026-Q1 |
| KENNEDY CAPITAL MANAGEMENT LLC trimmed | 142,343 | $13M | 2.3% | 2026-Q1 |
| Russell Investments Group, Ltd. added | 135,069 | $12M | 2.1% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 128,002 | $11M | 2.0% | 2026-Q1 |
| DIMENSIONAL FUND ADVISORS LP added | 124,630 | $11M | 2.0% | 2026-Q1 |
| STATE STREET CORP added | 122,068 | $11M | 1.9% | 2026-Q1 |
| RAYMOND JAMES FINANCIAL INC added | 122,911 | $11M | 1.9% | 2026-Q1 |
| MONIMUS CAPITAL MANAGEMENT, LP added | 101,292 | $9M | 1.6% | 2026-Q1 |
| CRAWFORD INVESTMENT COUNSEL INC added | 95,535 | $8M | 1.5% | 2026-Q1 |
| Roubaix Capital, LLC added | 72,115 | $6M | 1.1% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 70,617 | $6M | 1.1% | 2026-Q1 |
| JANUS HENDERSON GROUP PLC trimmed | 69,401 | $6M | 1.1% | 2026-Q1 |
| NORTHERN TRUST CORP added | 69,264 | $6M | 1.1% | 2026-Q1 |
| Meros Investment Management, LP trimmed | 68,032 | $6M | 1.1% | 2026-Q1 |
| GABELLI FUNDS LLC added | 62,499 | $6M | 1.0% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 62,424 | $6M | 1.0% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 57,871 | $5M | 0.9% | 2026-Q1 |
| D. E. Shaw & Co., Inc. trimmed | 54,558 | $5M | 0.9% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 52,586 | $5M | 0.8% | 2026-Q1 |
| WASATCH ADVISORS LP added | 51,233 | $5M | 0.8% | 2026-Q1 |
| HERALD INVESTMENT MANAGEMENT Ltd | 50,000 | $4M | 0.8% | 2026-Q1 |
| JACOBS LEVY EQUITY MANAGEMENT, INC added | 44,417 | $4M | 0.7% | 2026-Q1 |
| Bank of New York Mellon Corp trimmed | 43,937 | $4M | 0.7% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 38,337 | $3M | 0.6% | 2026-Q1 |
| RENAISSANCE TECHNOLOGIES LLC added | 31,600 | $3M | 0.5% | 2026-Q1 |
| BBR PARTNERS, LLC | 25,195 | $2M | 0.4% | 2026-Q1 |
| FRANKLIN RESOURCES INC trimmed | 21,553 | $2M | 0.3% | 2026-Q1 |
| LAZARD ASSET MANAGEMENT LLC added | 20,328 | $2M | 0.3% | 2026-Q1 |
| STATE OF WISCONSIN INVESTMENT BOARD trimmed | 19,006 | $2M | 0.3% | 2026-Q1 |
| Trexquant Investment LP trimmed | 18,661 | $2M | 0.3% | 2026-Q1 |
| KING LUTHER CAPITAL MANAGEMENT CORP | 17,411 | $2M | 0.3% | 2026-Q1 |
| SEGALL BRYANT & HAMILL, LLC trimmed | 18,174 | $1M | 0.3% | 2026-Q1 |
| TWO SIGMA INVESTMENTS, LP added | 16,359 | $1M | 0.3% | 2026-Q1 |
| Point72 Asset Management, L.P. added | 16,309 | $1M | 0.3% | 2026-Q1 |
| Creative Planning added | 14,994 | $1M | 0.2% | 2026-Q1 |
| RICE HALL JAMES & ASSOCIATES, LLC added | 14,222 | $1M | 0.2% | 2026-Q1 |
| CenterBook Partners LP new | 14,194 | $1M | 0.2% | 2026-Q1 |
| Invesco Ltd. added | 14,103 | $1M | 0.2% | 2026-Q1 |
| PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO | 13,722 | $1M | 0.2% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC trimmed | 13,373 | $1M | 0.2% | 2026-Q1 |
| ROYAL BANK OF CANADA added | 13,275 | $1M | 0.2% | 2026-Q1 |
| UBS Group AG added | 12,046 | $1M | 0.2% | 2026-Q1 |
| STIFEL FINANCIAL CORP added | 11,363 | $1M | 0.2% | 2026-Q1 |
| PRINCIPAL FINANCIAL GROUP INC trimmed | 11,088 | $980K | 0.2% | 2026-Q1 |
| Numerai GP LLC trimmed | 10,952 | $968K | 0.2% | 2026-Q1 |
| GLOBEFLEX CAPITAL L P new | 10,838 | $958K | 0.2% | 2026-Q1 |
| Nuveen, LLC added | 10,139 | $896K | 0.2% | 2026-Q1 |
| IEQ CAPITAL, LLC new | 9,658 | $854K | 0.2% | 2026-Q1 |
| Connor, Clark & Lunn Investment Management Ltd. trimmed | 9,517 | $841K | 0.2% | 2026-Q1 |
| Mariner, LLC added | 8,966 | $793K | 0.1% | 2026-Q1 |
| Quadrature Capital Ltd trimmed | 8,693 | $769K | 0.1% | 2026-Q1 |
| ENVESTNET ASSET MANAGEMENT INC added | 8,624 | $763K | 0.1% | 2026-Q1 |
| CITADEL ADVISORS LLC trimmed | 8,423 | $745K | 0.1% | 2026-Q1 |
| GAMCO INVESTORS, INC. ET AL added | 7,834 | $693K | 0.1% | 2026-Q1 |
| Vident Advisory, LLC new | 7,608 | $673K | 0.1% | 2026-Q1 |
| SEI INVESTMENTS CO trimmed | 7,403 | $655K | 0.1% | 2026-Q1 |
| Cerity Partners LLC added | 7,245 | $641K | 0.1% | 2026-Q1 |
| TUDOR INVESTMENT CORP ET AL trimmed | 6,874 | $608K | 0.1% | 2026-Q1 |
| CANADA PENSION PLAN INVESTMENT BOARD added | 6,800 | $601K | 0.1% | 2026-Q1 |
| RHUMBLINE ADVISERS trimmed | 6,547 | $579K | 0.1% | 2026-Q1 |
| FMR LLC added | 6,470 | $572K | 0.1% | 2026-Q1 |
| Y-Intercept (Hong Kong) Ltd added | 6,315 | $558K | 0.1% | 2026-Q1 |
| XTX Topco Ltd trimmed | 6,201 | $548K | 0.1% | 2026-Q1 |
| CWM, LLC added | 5,809 | $514K | 0.1% | 2026-Q1 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. added | 5,316 | $470K | 0.1% | 2026-Q1 |
| Conestoga Capital Advisors, LLC trimmed | 426,457 | $29M | 5.1% | 2025-Q3 stale |
| VANGUARD GROUP INC added | 321,899 | $25M | 4.5% | 2025-Q4 stale |
| GLENMEDE TRUST CO NA trimmed | 146,544 | $17M | 3.1% | 2025-Q1 stale |
| GENEVA CAPITAL MANAGEMENT LLC trimmed | 178,713 | $14M | 2.5% | 2025-Q4 stale |
| Simcoe Capital Management, LLC new | 190,929 | $13M | 2.3% | 2025-Q3 stale |
| Kent Lake PR LLC new | 134,516 | $9M | 1.6% | 2025-Q3 stale |
| MASON CAPITAL MANAGEMENT LLC | 70,300 | $6M | 1.0% | 2025-Q4 stale |
| JANE STREET GROUP, LLC added | 56,371 | $4M | 0.8% | 2025-Q4 stale |
| AMERIPRISE FINANCIAL INC trimmed | 39,095 | $3M | 0.5% | 2025-Q3 stale |
| Cubist Systematic Strategies, LLC added | 35,988 | $2M | 0.4% | 2025-Q3 stale |
| Qube Research & Technologies Ltd trimmed | 28,130 | $2M | 0.4% | 2025-Q4 stale |
| WELLINGTON MANAGEMENT GROUP LLP added | 22,471 | $2M | 0.4% | 2025-Q2 stale |
| Irenic Capital Management LP new | 25,000 | $2M | 0.4% | 2025-Q4 stale |
| Keeley-Teton Advisors, LLC trimmed | 15,678 | $2M | 0.3% | 2025-Q1 stale |
| PUBLIC SECTOR PENSION INVESTMENT BOARD added | 18,528 | $2M | 0.3% | 2025-Q2 stale |
| UBS AM, A DISTINCT BUSINESS UNIT OF UBS ASSET MANAGEMENT AMERICAS LLC trimmed | 17,403 | $2M | 0.3% | 2025-Q2 stale |
| Swiss National Bank trimmed | 10,402 | $980K | 0.2% | 2025-Q2 stale |
| GSA CAPITAL PARTNERS LLP added | 11,614 | $912K | 0.2% | 2025-Q4 stale |
| VICTORY CAPITAL MANAGEMENT INC added | 10,455 | $701K | 0.1% | 2025-Q3 stale |
| CANADA LIFE ASSURANCE Co | 6,927 | $653K | 0.1% | 2025-Q2 stale |
| MACKENZIE FINANCIAL CORP trimmed | 5,247 | $623K | 0.1% | 2025-Q1 stale |
| MARSHALL WACE, LLP trimmed | 7,137 | $560K | 0.1% | 2025-Q4 stale |
| ExodusPoint Capital Management, LP trimmed | 6,937 | $545K | 0.1% | 2025-Q4 stale |
| PRUDENTIAL FINANCIAL INC added | 5,658 | $533K | 0.1% | 2025-Q2 stale |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP new | 6,228 | $489K | 0.1% | 2025-Q4 stale |
| Dynamic Technology Lab Private Ltd added | 6,190 | $486K | 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.