Who owns IDEXX Laboratories, Inc. (IDXX)
Which tracked institutional funds hold IDXX, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See IDXX company fundamentals →
Ownership as of the 2026-Q1 13F filings (latest filed 2026-07-15). 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 IDXX is one-sided between 2025-Q4 and 2026-Q1: 139 added or opened and 583 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
IDXX’s largest tracked holder by dollar value, VANGUARD GROUP INC, sizes it at 0.1% of its own reported 13F book, while the median holder sizes it at 0.1% of theirs — a 0.0pp gap the other way — the median holder sizes IDXX more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in IDXX 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 1306 tracked filers holding IDXX, 550 increased or opened the position and 719 reduced or closed it; over the same quarter, open-market insider Form 4 buying and selling roughly offset.
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 IDXX 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 52
- VANGUARD CAPITAL MANAGEMENT LLC$2.9B
- VANGUARD PORTFOLIO MANAGEMENT LLC$2.2B
- Capital World Investors$280M
- VANGUARD FIDUCIARY TRUST CO$259M
- CIBC Bancorp USA Inc.$207M
- Alyeska Investment Group, L.P.$114M
Full exits 54
- VANGUARD GROUP INC$6.7B
- CIBC Private Wealth Group LLC$245M
- VIRGINIA RETIREMENT SYSTEMS ET Al$45M
- Zurich Insurance Group Ltd/FI$45M
- CIBC WORLD MARKETS CORP$29M
- FORSTA AP-FONDEN$24M
Largest adds
- ARROWSTREET CAPITAL, LIMITED PARTNERSHIP$99M
- MONTRUSCO BOLTON INVESTMENTS INC.$70M
- Point72 Asset Management, L.P.$65M
- Holocene Advisors, LP$52M
- AustralianSuper Pty Ltd$46M
- Pictet Asset Management Holding SA$45M
Largest trims
- BlackRock, Inc.$1.7B
- Fundsmith LLP$446M
- STATE STREET CORP$409M
- MORGAN STANLEY$312M
- BAMCO INC /NY/$299M
- PRICE T ROWE ASSOCIATES INC /MD/$286M
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. trimmed | 7,212,542 | $4.1B | 10.0% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 5,182,507 | $2.9B | 7.2% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 3,910,863 | $2.2B | 5.4% | 2026-Q1 |
| STATE STREET CORP added | 3,674,185 | $2.1B | 5.1% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 2,660,999 | $1.5B | 3.7% | 2026-Q1 |
| Invesco Ltd. added | 1,671,121 | $939M | 2.3% | 2026-Q1 |
| BAMCO INC /NY/ trimmed | 1,633,367 | $918M | 2.3% | 2026-Q1 |
| Bank of New York Mellon Corp trimmed | 1,504,532 | $845M | 2.1% | 2026-Q1 |
| Fundsmith LLP trimmed | 1,465,786 | $824M | 2.0% | 2026-Q1 |
| MORGAN STANLEY trimmed | 1,315,954 | $739M | 1.8% | 2026-Q1 |
| BLAIR WILLIAM & CO/IL trimmed | 946,336 | $532M | 1.3% | 2026-Q1 |
| NORTHERN TRUST CORP trimmed | 911,893 | $512M | 1.3% | 2026-Q1 |
| PRINCIPAL FINANCIAL GROUP INC trimmed | 881,189 | $495M | 1.2% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 871,789 | $490M | 1.2% | 2026-Q1 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 838,839 | $471M | 1.2% | 2026-Q1 |
| Capital Research Global Investors added | 781,345 | $439M | 1.1% | 2026-Q1 |
| JPMORGAN CHASE & CO added | 779,882 | $434M | 1.1% | 2026-Q1 |
| WELLINGTON MANAGEMENT GROUP LLP trimmed | 733,304 | $412M | 1.0% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC trimmed | 716,921 | $403M | 1.0% | 2026-Q1 |
| POLEN CAPITAL MANAGEMENT LLC trimmed | 695,811 | $391M | 1.0% | 2026-Q1 |
| FRANKLIN RESOURCES INC added | 662,633 | $372M | 0.9% | 2026-Q1 |
| Legal & General Group Plc trimmed | 650,803 | $366M | 0.9% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 638,063 | $359M | 0.9% | 2026-Q1 |
| Amundi trimmed | 610,779 | $343M | 0.8% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 610,217 | $343M | 0.8% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC trimmed | 599,931 | $337M | 0.8% | 2026-Q1 |
| DIMENSIONAL FUND ADVISORS LP added | 573,332 | $322M | 0.8% | 2026-Q1 |
| Capital World Investors trimmed | 497,851 | $280M | 0.7% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 488,017 | $274M | 0.7% | 2026-Q1 |
| FUNDSMITH INVESTMENT SERVICES LTD. trimmed | 481,586 | $271M | 0.7% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 460,656 | $259M | 0.6% | 2026-Q1 |
| Nuveen, LLC trimmed | 445,804 | $250M | 0.6% | 2026-Q1 |
| AustralianSuper Pty Ltd added | 443,022 | $249M | 0.6% | 2026-Q1 |
| CAPITAL COUNSEL LLC/NY trimmed | 420,195 | $236M | 0.6% | 2026-Q1 |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. trimmed | 399,376 | $224M | 0.6% | 2026-Q1 |
| ROYAL BANK OF CANADA trimmed | 391,704 | $220M | 0.5% | 2026-Q1 |
| DEUTSCHE BANK AG\ added | 388,813 | $218M | 0.5% | 2026-Q1 |
| CIBC Bancorp USA Inc. added | 367,502 | $207M | 0.5% | 2026-Q1 |
| WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC trimmed | 351,621 | $198M | 0.5% | 2026-Q1 |
| NEUBERGER BERMAN GROUP LLC added | 349,707 | $196M | 0.5% | 2026-Q1 |
| MONTRUSCO BOLTON INVESTMENTS INC. added | 342,120 | $187M | 0.5% | 2026-Q1 |
| BESSEMER GROUP INC added | 319,265 | $179M | 0.4% | 2026-Q1 |
| Clearbridge Investments, LLC added | 308,477 | $173M | 0.4% | 2026-Q1 |
| UBS Group AG added | 305,167 | $171M | 0.4% | 2026-Q1 |
| Pictet Asset Management Holding SA added | 287,937 | $162M | 0.4% | 2026-Q1 |
| FMR LLC added | 282,939 | $159M | 0.4% | 2026-Q1 |
| RAYMOND JAMES FINANCIAL INC added | 272,955 | $153M | 0.4% | 2026-Q1 |
| Williams Jones Wealth Management, LLC. trimmed | 263,513 | $148M | 0.4% | 2026-Q1 |
| Caisse de depot et placement du Quebec added | 263,051 | $148M | 0.4% | 2026-Q1 |
| NORGES BANK trimmed | 347,963 | $146M | 0.4% | 2026-Q1 |
| Railway Pension Investments Ltd trimmed | 256,480 | $144M | 0.4% | 2026-Q1 |
| TD Asset Management Inc trimmed | 236,531 | $133M | 0.3% | 2026-Q1 |
| FIRST TRUST ADVISORS LP trimmed | 234,653 | $132M | 0.3% | 2026-Q1 |
| Swiss National Bank added | 234,380 | $132M | 0.3% | 2026-Q1 |
| LOS ANGELES CAPITAL MANAGEMENT LLC added | 227,369 | $128M | 0.3% | 2026-Q1 |
| COMGEST GLOBAL INVESTORS S.A.S. added | 220,354 | $124M | 0.3% | 2026-Q1 |
| WELLS FARGO & COMPANY/MN added | 208,847 | $117M | 0.3% | 2026-Q1 |
| Allianz Asset Management GmbH trimmed | 207,403 | $117M | 0.3% | 2026-Q1 |
| Alyeska Investment Group, L.P. trimmed | 203,274 | $114M | 0.3% | 2026-Q1 |
| Russell Investments Group, Ltd. added | 201,694 | $113M | 0.3% | 2026-Q1 |
| Sumitomo Mitsui Trust Group, Inc. trimmed | 197,871 | $111M | 0.3% | 2026-Q1 |
| Robeco Institutional Asset Management B.V. added | 189,760 | $107M | 0.3% | 2026-Q1 |
| Mitsubishi UFJ Asset Management Co., Ltd. added | 189,020 | $106M | 0.3% | 2026-Q1 |
| SCHRODER INVESTMENT MANAGEMENT GROUP trimmed | 188,125 | $106M | 0.3% | 2026-Q1 |
| BARCLAYS PLC trimmed | 187,715 | $105M | 0.3% | 2026-Q1 |
| VICTORY CAPITAL MANAGEMENT INC trimmed | 183,237 | $103M | 0.3% | 2026-Q1 |
| ENVESTNET ASSET MANAGEMENT INC added | 183,097 | $103M | 0.3% | 2026-Q1 |
| Liontrust Investment Partners LLP | 150,780 | $102M | 0.3% | 2026-Q1 |
| Vanguard Global Advisers, LLC new | 174,862 | $98M | 0.2% | 2026-Q1 |
| Epoch Investment Partners, Inc. trimmed | 174,602 | $98M | 0.2% | 2026-Q1 |
| RHUMBLINE ADVISERS added | 173,731 | $98M | 0.2% | 2026-Q1 |
| KBC Group NV trimmed | 172,679 | $97M | 0.2% | 2026-Q1 |
| Welch & Forbes LLC trimmed | 168,181 | $94M | 0.2% | 2026-Q1 |
| CONGRESS ASSET MANAGEMENT CO added | 166,686 | $94M | 0.2% | 2026-Q1 |
| HSBC HOLDINGS PLC added | 166,251 | $93M | 0.2% | 2026-Q1 |
| AMERICAN CAPITAL MANAGEMENT INC trimmed | 166,056 | $93M | 0.2% | 2026-Q1 |
| TimesSquare Capital Management, LLC trimmed | 163,763 | $92M | 0.2% | 2026-Q1 |
| FEDERATED HERMES, INC. added | 156,675 | $88M | 0.2% | 2026-Q1 |
| California Public Employees Retirement System trimmed | 156,525 | $88M | 0.2% | 2026-Q1 |
| Holocene Advisors, LP added | 147,732 | $83M | 0.2% | 2026-Q1 |
| VANGUARD ASSET MANAGEMENT, Ltd new | 139,492 | $78M | 0.2% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS trimmed | 138,726 | $78M | 0.2% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC trimmed | 134,296 | $75M | 0.2% | 2026-Q1 |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND added | 133,891 | $75M | 0.2% | 2026-Q1 |
| WESTFIELD CAPITAL MANAGEMENT CO LP trimmed | 132,860 | $75M | 0.2% | 2026-Q1 |
| Point72 Asset Management, L.P. added | 129,284 | $73M | 0.2% | 2026-Q1 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed | 122,654 | $69M | 0.2% | 2026-Q1 |
| ProShare Advisors LLC trimmed | 122,618 | $69M | 0.2% | 2026-Q1 |
| LORING WOLCOTT & COOLIDGE FIDUCIARY ADVISORS LLP/MA trimmed | 122,304 | $69M | 0.2% | 2026-Q1 |
| National Pension Service added | 122,420 | $69M | 0.2% | 2026-Q1 |
| Corient Private Wealth LLC trimmed | 122,006 | $69M | 0.2% | 2026-Q1 |
| Rathbones Group PLC added | 121,511 | $68M | 0.2% | 2026-Q1 |
| Bank Julius Baer & Co. Ltd, Zurich trimmed | 121,515 | $68M | 0.2% | 2026-Q1 |
| CITIGROUP INC added | 120,283 | $68M | 0.2% | 2026-Q1 |
| TCW GROUP INC added | 118,751 | $67M | 0.2% | 2026-Q1 |
| VANGUARD GROUP INC trimmed | 9,945,328 | $6.7B | 16.7% | 2025-Q4 stale |
| CIBC Private Wealth Group LLC trimmed | 362,871 | $245M | 0.6% | 2025-Q4 stale |
| GENERATION INVESTMENT MANAGEMENT LLP trimmed | 260,394 | $166M | 0.4% | 2025-Q3 stale |
| Durable Capital Partners LP added | 364,757 | $153M | 0.4% | 2025-Q1 stale |
| Champlain Investment Partners, LLC trimmed | 192,226 | $103M | 0.3% | 2025-Q2 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.