IDEXX LABORATORIES INC (IDXX) Institutional Shareholders
IDEXX LABORATORIES INC (IDXX) is currently reported in institutional portfolios tracked by InsiderSet based on the latest available SEC Form 13F filings for the quarter ended March 31, 2026. The institutional investors covered on this page collectively reported approximately $38.31B in IDXX holdings during the latest filing period.
Blackrock, Inc. is currently the largest disclosed institutional shareholder of IDXX tracked by InsiderSet, reporting ownership valued at approximately $4.70B in its March 31, 2026 SEC Form 13F filing. Based on current market prices and the latest disclosed share count, the position is now estimated to be worth approximately $4.68B, representing an estimated loss of -0.50% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 46% of the total disclosed IDXX value among the investors covered in this analysis. Major shareholders include Blackrock, Inc., Vanguard Capital Management Llc, Vanguard Portfolio Management Llc, and several other long-term asset managers with concentrated positions in IDEXX LABORATORIES INC (IDXX).
This page ranks the largest institutional IDXX shareholders using publicly disclosed SEC Form 13F data, including reported values, estimated current holding values, portfolio allocation percentages, ownership concentration metrics, and historical holding changes across major hedge funds and investment firms.
Institutional Holders
1,278
Total Reported Value
$38.31B
Largest Holder
Blackrock, Inc.
Largest Position
$4.70B
Insider Transactions (90d)
2
Latest Filing Quarter
Q2 2026
New Institutional Positions
21
Funds Exiting Positions
0
| Name | Investor/Manager | Portfolio % | Quantity | Reported Balance | Current Estimated Value | Gain/loss Since Filing | Estimated Portfolio Performance |
|---|---|---|---|---|---|---|---|
| Blackrock, Inc. | 0.08% | 8,365,553 | $4,700,520,591 | $4,676,929,716 | -$23,590,875 | -0.50% | |
| Vanguard Capital Management Llc | 0.07% | 5,182,507 | $2,911,998,858 | $2,897,384,188 | -$14,614,670 | -0.50% | |
| Vanguard Portfolio Management Llc | 0.12% | 3,910,863 | $2,197,474,811 | $2,186,446,177 | -$11,028,634 | -0.50% | |
| State Street Corp | 0.07% | 3,674,185 | $2,064,487,810 | $2,054,126,608 | -$10,361,202 | -0.50% | |
| Geode Capital Management, Llc | 0.09% | 2,660,999 | $1,497,768,297 | $1,487,684,711 | -$10,083,586 | -0.67% | |
| Invesco Ltd. | 0.14% | 1,678,045 | $942,876,970 | $938,144,618 | -$4,732,352 | -0.50% | |
| Bamco Inc | 2.77% | 1,633,367 | $917,772,584 | $913,166,489 | -$4,606,095 | -0.50% | |
| Bank Of New York Mellon Corp | 0.16% | 1,504,532 | $845,381,140 | $841,138,705 | -$4,242,435 | -0.50% | |
| Fundsmith | Terry Smith | 6.42% | 1,465,786 | $823,610,496 | $819,476,979 | -$4,133,517 | -0.50% |
| Morgan Stanley | 0.04% | 1,315,954 | $739,423,426 | $735,710,403 | -$3,713,023 | -0.50% | |
| Blair William & Co/Il | 1.52% | 946,336 | $531,736,581 | $529,068,068 | -$2,668,513 | -0.50% | |
| Northern Trust Corp | 0.07% | 911,893 | $512,383,559 | $509,812,020 | -$2,571,539 | -0.50% | |
| Principal Financial Group Inc | 0.26% | 881,189 | $495,164,014 | $492,646,334 | -$2,517,680 | -0.51% | |
| Ubs Am, A Distinct Business Unit Of Ubs Asset Management Americas Llc | 0.10% | 871,789 | $489,849,521 | $487,391,076 | -$2,458,445 | -0.50% | |
| Arrowstreet Capital, Limited Partnership | 0.26% | 838,839 | $471,335,246 | $468,969,720 | -$2,365,526 | -0.50% | |
| Capital Research Global Investors | 0.07% | 781,345 | $439,007,277 | $436,826,549 | -$2,180,728 | -0.50% | |
| Wellington Management Group Llp | 0.08% | 735,475 | $413,256,047 | $411,182,008 | -$2,074,039 | -0.50% | |
| Goldman Sachs Group Inc | 0.05% | 716,921 | $402,830,921 | $400,809,023 | -$2,021,898 | -0.50% | |
| Polen Capital Management | David M. Polen | 2.70% | 695,811 | $390,969,243 | $389,007,056 | -$1,962,187 | -0.50% |
| Franklin Resources Inc | 0.09% | 662,633 | $372,326,527 | $370,458,231 | -$1,868,296 | -0.50% | |
| Legal & General Group Plc | 0.08% | 650,803 | $365,679,700 | $363,844,433 | -$1,835,267 | -0.50% | |
| Amundi | 0.09% | 610,779 | $343,190,612 | $341,468,216 | -$1,722,396 | -0.50% | |
| Charles Schwab Investment Management Inc | 0.05% | 610,217 | $342,874,830 | $341,154,018 | -$1,720,812 | -0.50% | |
| American Century Companies Inc | 0.17% | 599,931 | $337,095,230 | $335,403,424 | -$1,691,806 | -0.50% | |
| Storebrand Asset Management As | 0.11% | 721,451 | $335,936,782 | $403,341,611 | +$67,404,829 | +20.06% | |
| Dimensional Fund Advisors Lp | 0.07% | 573,332 | $322,144,900 | $320,532,721 | -$1,612,179 | -0.50% | |
| Capital World Investors | 0.04% | 497,851 | $279,737,344 | $278,333,559 | -$1,403,785 | -0.50% | |
| Bank Of America Corp | 0.02% | 488,017 | $274,211,972 | $272,835,664 | -$1,376,308 | -0.50% | |
| Fundsmith Investment Services | Terry Smith | 6.14% | 481,586 | $270,598,358 | $269,240,285 | -$1,358,073 | -0.50% |
| Vanguard Fiduciary Trust Co | 0.07% | 460,656 | $258,838,000 | $257,538,950 | -$1,299,050 | -0.50% | |
| Nuveen, Llc | 0.07% | 445,804 | $250,492,810 | $249,235,642 | -$1,257,168 | -0.50% | |
| Australiansuper Pty Ltd | 1.30% | 443,022 | $248,929,632 | $247,680,310 | -$1,249,322 | -0.50% | |
| Nomura Asset Management International Inc. | 0.38% | 399,376 | $224,405,000 | $223,279,140 | -$1,125,860 | -0.50% | |
| Royal Bank Of Canada | 0.04% | 391,704 | $220,095,000 | $218,989,955 | -$1,105,045 | -0.50% | |
| Deutsche Bank Ag\ | 0.07% | 388,813 | $218,470,137 | $217,373,684 | -$1,096,453 | -0.50% | |
| Cibc Bancorp Usa Inc. | 0.28% | 367,502 | $206,501,881 | $205,459,343 | -$1,042,538 | -0.50% | |
| William Blair Investment Management, Llc | 0.65% | 351,621 | $197,572,324 | $196,580,752 | -$991,572 | -0.50% | |
| Neuberger Berman Group Llc | 0.15% | 349,707 | $196,496,975 | $195,510,692 | -$986,283 | -0.50% | |
| Montrusco Bolton Investments Inc. | 3.04% | 372,788 | $196,250,515 | $208,414,587 | +$12,164,072 | +6.20% | |
| Clearbridge Investments, Llc | 0.15% | 308,477 | $173,329,939 | $172,460,236 | -$869,703 | -0.50% | |
| Ubs Group Ag | 0.03% | 305,167 | $171,470,285 | $170,609,715 | -$860,570 | -0.50% | |
| Fmr Llc | 0.01% | 282,976 | $159,001,286 | $158,203,392 | -$797,894 | -0.50% | |
| Raymond James Financial Inc | 0.05% | 272,955 | $152,516,740 | $152,600,952 | +$84,212 | +0.06% | |
| Williams Jones Wealth Management, Llc. | 1.82% | 263,513 | $148,065,320 | $147,322,213 | -$743,107 | -0.50% | |
| Caisse De Depot Et Placement Du Quebec | 0.24% | 263,051 | $147,805,726 | $147,063,923 | -$741,803 | -0.50% | |
| Railway Pension Investments Ltd | 2.05% | 256,480 | $144,113,547 | $143,390,274 | -$723,273 | -0.50% | |
| Comgest Global Investors S.A.S. | 3.04% | 262,562 | $138,223,139 | $146,790,537 | +$8,567,398 | +6.20% | |
| Td Asset Management Inc | 0.11% | 236,531 | $132,904,404 | $132,237,386 | -$667,018 | -0.50% | |
| First Trust Advisors Lp | 0.09% | 234,653 | $131,849,087 | $131,187,453 | -$661,634 | -0.50% | |
| Swiss National Bank | 0.08% | 234,380 | $131,695,778 | $131,034,827 | -$660,951 | -0.50% |
Frequently asked questions about IDXX
Who owns the most IDXX stock?
The largest holders of IDXX are typically major institutional investors such as asset managers and hedge funds reporting on Form 13F. The table above ranks tracked superinvestors by reported position size using the latest available filings for IDEXX LABORATORIES INC (IDXX).
Is IDXX widely held by superinvestors?
Many widely followed stocks like IDXX appear across numerous superinvestor portfolios because of liquidity, index inclusion, and fundamentals. The holder count and table above show how broadly IDXX is represented among the institutional managers we track.
What do “Current Estimated Value”, “Gain/loss Since Filing”, and “Estimated Portfolio Performance” mean?
Current Estimated Value is reported share quantity from the latest 13F times our most recent split-adjusted U.S. session close. Gain/loss Since Filing is that estimate minus the reported 13F dollar value; Estimated Portfolio Performance is that difference as a percent of the reported value. Green means the estimate is above the filing value; red means below (not purchase cost). If many filers share the same implied filing price per share, the performance % may match across rows. These are not official fund marks or live quotes.