IDEXX Laboratories, Inc. (IDXX) Ownership
IDXX ownership summary
as of October 18, 2026- Institutions
- 96.6% of shares outstanding
- Insiders
- 0.22% of shares outstanding
- Shares outstanding
- 78.9M
- Float
- 78.5M shares available to trade
- Short interest
- 2.82% 1.9M shares short
- Days to cover
- 3.75 short interest up 1.2% vs prior month
- Institutions 96.64%
- Insiders 0.22%
- Other investors 3.14%
IDXX top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | BlackRock Inc | 10.37% | 8.2M | $4.58B | −195,375 (−2.3%) | June 30, 2026 |
| 2 | Vanguard Capital Management, LLC | 6.54% | 5.2M | $2.89B | −30,294 (−0.6%) | June 30, 2026 |
| 3 | Vanguard Portfolio Management, LLC | 4.95% | 3.9M | $2.18B | −14,342 (−0.4%) | June 30, 2026 |
| 4 | State Street Corp | 4.76% | 3.7M | $2.10B | +74,475 (+2.0%) | June 30, 2026 |
| 5 | Amvescap Plc. | 4.58% | 3.6M | $2.02B | +261,739 (+7.8%) | June 30, 2026 |
| 6 | Geode Capital Management, LLC | 3.25% | 2.6M | $1.44B | −98,113 (−3.7%) | June 30, 2026 |
| 7 | BAMCO Inc | 2.51% | 2.0M | $1.11B | +343,411 (+21.0%) | June 30, 2026 |
| 8 | Morgan Stanley - Brokerage Accounts | 1.72% | 1.4M | $759.9M | +40,149 (+3.1%) | June 30, 2026 |
| 9 | Bank of New York Mellon Corp | 1.51% | 1.2M | $668.7M | −311,189 (−20.7%) | June 30, 2026 |
| 10 | Arrowstreet Capital Limited Partnership | 1.35% | 1.1M | $597.9M | +228,239 (+27.2%) | June 30, 2026 |
| 11 | Fundsmith LLP | 1.29% | 1.0M | $571.5M | −445,899 (−30.4%) | June 30, 2026 |
| 12 | Blair William & Co | 1.17% | 919K | $514.7M | −27,780 (−2.9%) | June 30, 2026 |
| 13 | Northern Trust Corp | 1.17% | 918K | $514.5M | +6,244 (+0.7%) | June 30, 2026 |
| 14 | UBS Asset Mgmt Americas Inc | 1.16% | 911K | $510.8M | +39,700 (+4.6%) | June 30, 2026 |
| 15 | FMR Inc | 1.04% | 823K | $461.0M | +539,667 (+190.7%) | June 30, 2026 |
| 16 | American Century Companies Inc | 1.03% | 808K | $453.0M | +208,427 (+34.7%) | June 30, 2026 |
| 17 | Capital Research Global Investors | 1.00% | 789K | $442.2M | +7,766 (+1.0%) | June 30, 2026 |
| 18 | JPMorgan Chase & Co | 0.96% | 756K | $423.5M | −24,091 (−3.1%) | June 30, 2026 |
| 19 | Principal Financial Group Inc | 0.94% | 743K | $416.5M | −137,943 (−15.7%) | June 30, 2026 |
| 20 | The Goldman Sachs Group Inc | 0.94% | 739K | $413.9M | +21,787 (+3.0%) | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 11 holders added 1.8M shares and 9 cut 1.3M.
IDXX top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Vanguard MStar Total Stk Mkt Idx Invest | 3.18% | 2.5M | $1.40B | −5,308 (−0.2%) | August 31, 2026 |
| 2 | Vanguard 500 Index Investor | 2.63% | 2.1M | $1.16B | −25,512 (−1.2%) | September 30, 2026 |
| 3 | Vanguard MStar Mid Cap Index Instl | 2.14% | 1.7M | $945.3M | −19,307 (−1.1%) | September 30, 2026 |
| 4 | Invesco QQQ Trust | 2.09% | 1.6M | $921.8M | −2,684 (−0.2%) | September 30, 2026 |
| 5 | iShares Core S&P 500 ETF | 1.33% | 1.1M | $588.4M | −1,702 (−0.2%) | September 30, 2026 |
| 6 | Fidelity 500 Index | 1.30% | 1.0M | $573.8M | +3,934 (+0.4%) | August 31, 2026 |
| 7 | Vanguard MStar Growth Index Investor | 1.27% | 1.0M | $561.5M | +67,990 (+7.3%) | September 30, 2026 |
| 8 | State Street® SPDR® S&P 500® ETF | 1.23% | 971K | $544.0M | — | September 30, 2026 |
| 9 | Baron Partners Retail | 1.01% | 798K | $447.2M | −48,206 (−5.7%) | September 30, 2026 |
| 10 | American Funds AMCAP A | 0.93% | 733K | $410.7M | — | September 30, 2026 |
| 11 | Vanguard MStar Mid Cap Growth ETF | 0.79% | 618K | $346.6M | +12,497 (+2.1%) | September 30, 2026 |
| 12 | State Street®HlthCrSelSectSPDR®ETF | 0.71% | 559K | $313.1M | +1,744 (+0.3%) | September 30, 2026 |
| 13 | Vanguard US Growth Investor | 0.71% | 557K | $311.9M | +249,247 (+81.1%) | June 30, 2026 |
| 14 | T. Rowe Price Mid-Cap Growth | 0.68% | 532K | $298.1M | — | September 30, 2026 |
| 15 | Vanguard Institutional Index I | 0.53% | 417K | $233.4M | −5,279 (−1.3%) | September 30, 2026 |
| 16 | Invesco S&P 500® Equal Weight ETF | 0.48% | 380K | $212.8M | −760 (−0.2%) | September 30, 2026 |
| 17 | iShares Russell Mid-Cap Growth ETF | 0.47% | 374K | $209.4M | −399 (−0.1%) | September 30, 2026 |
| 18 | Fundsmith Equity I Acc | 0.47% | 374K | $209.3M | −18,630 (−4.8%) | June 30, 2026 |
| 19 | Invesco NASDAQ 100 ETF | 0.46% | 362K | $202.9M | +840 (+0.2%) | September 30, 2026 |
| 20 | Fidelity Contrafund | 0.45% | 351K | $196.6M | −115 (−0.0%) | August 31, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
IDXX insider transactions
latest 20| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-03-30 | Ro Khanna | Buy | $557.09 | — | — |
| 2026-03-03 | Nimrata Hunt | Sell | $634.57 | 1,758 | $1.1M |
| 2026-02-26 | Jonathan Jay Mazelsky | Sell | $657.55 | 23,326 | $15.3M |
| 2026-02-26 | Nimrata Hunt | Sell | $661.54 | 2,693 | $1.8M |
| 2026-02-24 | Ro Khanna | Buy | $649.35 | — | — |
| 2026-02-17 | Michael G Erickson | Sell | $627.38 | 5,371 | $3.4M |
| 2026-02-17 | Sophie V Vandebroek | Sell | $628.62 | 1,464 | $920,300 |
| 2026-02-17 | Ro Khanna | Sell | $626.17 | — | — |
| 2026-02-10 | George Fennell | Sell | $646.72 | 11,345 | $7.3M |
| 2026-01-23 | Ro Khanna | Sell | $693.85 | — | — |
| 2026-01-13 | April McClain Delaney | Sell | $714.04 | — | — |
| 2025-11-07 | Nimrata Hunt | Sell | $703.34 | 9,425 | $6.6M |
| 2025-10-16 | April McClain Delaney | Sell | $637.34 | — | — |
| 2025-10-07 | Ro Khanna | Buy | $627.28 | — | — |
| 2025-09-05 | Ro Khanna | Sell | $642.99 | — | — |
| 2025-09-04 | Byron Donalds | Buy | $640.44 | — | — |
| 2025-08-22 | M Anne Szostak | Sell | $647.33 | 2,187 | $1.4M |
| 2025-08-12 | Michael G Erickson | Sell | $649.96 | 406 | $263,884 |
| 2025-08-11 | Nimrata Hunt | Sell | $656.53 | 1,200 | $787,836 |
| 2025-08-08 | Sharon E Underberg | Sell | $651.60 | 5,450 | $3.6M |
Reported trades by company officers, directors and other filers (including disclosures by members of Congress where EODHD lists them). "—" where the filing gives no share count.
IDXX shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns IDXX
Institutional investors own 96.6% of IDEXX's shares and insiders 0.22%. The largest holder is BlackRock Inc with 10.37% of the shares (8.2M), as of June 30, 2026. Among the top 20 institutions, 11 added shares and 9 reduced their stake in the latest filings. Short interest is 2.82% of the float, or 3.75 days of average trading volume. The share count fell 16.7% since 2014.
Related: IDXX analyst forecast, IDXX key metrics. See the IDXX stock overview for the latest quote and news.
IDXX ownership FAQ
Who owns the most IDEXX stock?
The largest shareholders of IDEXX are BlackRock Inc (10.37%), Vanguard Capital Management, LLC (6.54%), Vanguard Portfolio Management, LLC (4.95%), State Street Corp (4.76%), Amvescap Plc. (4.58%).
What percentage of IDEXX is owned by institutions?
Institutions hold 96.6% of IDEXX's shares outstanding; insiders hold 0.22%.
Which funds own IDEXX?
The largest fund holders of IDEXX are Vanguard MStar Total Stk Mkt Idx Invest (3.18%), Vanguard 500 Index Investor (2.63%), Vanguard MStar Mid Cap Index Instl (2.14%), Invesco QQQ Trust (2.09%), iShares Core S&P 500 ETF (1.33%).
What is IDEXX's short interest?
1.9M shares of IDEXX were sold short, 2.82% of the float; at the average daily volume it would take 3.75 days to cover.
Are insiders buying or selling IDEXX?
Of the latest 20 reported insider transactions in IDEXX (since August 8, 2025), 4 were purchases and 16 were sales.
How many shares of IDEXX are outstanding?
IDEXX has 78.9M shares outstanding, of which 78.5M are in the public float.