Idexx Laboratories (IDXX) Held by Superinvestors
IDEXX LABORATORIES INC (IDXX) is currently held by 8 superinvestors tracked by InsiderSet, with a combined reported market value of approximately $1.12B based on the latest available SEC Form 13F filings for the quarter ended June 30, 2026.
Fundsmith is currently the largest disclosed institutional shareholder of IDXX tracked by InsiderSet, reporting ownership valued at approximately $536.91M in its June 30, 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 $523.34M, representing an estimated loss of -2.53% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 100% of the total disclosed IDXX value among the investors covered in this analysis. Major shareholders include Fundsmith, Polen Capital Management, Fundsmith Investment Services, 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.
| Name | Investor/Manager | Portfolio % | Quantity | Reported Balance | Current Estimated Value | Gain/loss Since Filing | Estimated Portfolio Performance |
|---|---|---|---|---|---|---|---|
| Fundsmith | Terry Smith | 3.93% | 1,019,887 | $536,909,312 | $523,344,815 | -$13,564,497 | -2.53% |
| Polen Capital Management | David M. Polen | 2.41% | 532,384 | $280,268,269 | $273,187,526 | -$7,080,743 | -2.53% |
| Fundsmith Investment Services | Terry Smith | 3.81% | 327,058 | $172,176,414 | $167,826,542 | -$4,349,872 | -2.53% |
| Renaissance Technologies LLC | Jim Simons | 0.08% | 109,784 | $57,794,689 | $56,334,562 | -$1,460,127 | -2.53% |
| Jensen Investment Management | Eric H. Schoenstein | 1.35% | 105,709 | $55,649,446 | $54,243,516 | -$1,405,930 | -2.53% |
| Parnassus Endeavor Fund | Parnassus Investments | 0.04% | 29,386 | $15,469,966 | $15,079,132 | -$390,834 | -2.53% |
| Sequoia Financial Advisors | 0.01% | 4,243 | $2,233,474 | $2,177,253 | -$56,221 | -2.52% | |
| Mairs & Power Growth Fund | Andrew R. Adams | 0.01% | 2,080 | $1,094,995 | $1,067,331 | -$27,664 | -2.53% |
Frequently asked questions about IDXX
Who are the largest superinvestors holding IDXX?
The largest superinvestors holding IDXX in the latest SEC Form 13F filings include Fundsmith, Polen Capital Management, Fundsmith Investment Services, Renaissance Technologies LLC, and Jensen Investment Management. InsiderSet ranks these superinvestors by their latest reported IDXX position.
What does the IDXX superinvestors page include?
This page tracks IDXX positions reported by a curated group of notable institutional investors and fund managers through SEC Form 13F. IDEXX LABORATORIES INC (IDXX) on this page reflects disclosed 13F holdings among those superinvestors, not every institutional shareholder of the stock.
How many superinvestors hold IDXX?
InsiderSet currently tracks 8 superinvestors reporting IDXX holdings in the latest available 13F data. This is the curated set on this page, not the total number of institutions that own IDXX.
How much IDXX stock do superinvestors hold?
Superinvestors tracked by InsiderSet disclosed approximately $1.12B in IDXX holdings for Q2 2026. This figure is reported 13F value as of the filing period, not necessarily today's market value, and it covers the curated superinvestors on this page rather than every institutional filer.
When were IDXX superinvestor holdings last updated?
The latest IDXX superinvestor holdings on InsiderSet are based on SEC Form 13F filings for the quarter ended June 30, 2026. Form 13F filings are generally reported after the quarter ends, so the holdings shown represent the latest publicly disclosed positions rather than real-time holdings.
Are superinvestor IDXX holdings real-time?
No. Form 13F data is not real-time. It represents positions reported by these superinvestors as of the end of the reporting quarter. A superinvestor may have changed its IDXX position after the reporting date.
Are superinvestors buying or selling IDXX?
Buying and selling can be analyzed by comparing IDXX positions across consecutive 13F reporting periods. InsiderSet's IDXX Ownership Changes page shows institutions that increased, reduced, initiated, or exited positions based on reported 13F holdings. View IDXX ownership changes.
How have superinvestor IDXX holdings changed over time?
InsiderSet tracks IDXX holdings among these superinvestors across multiple 13F reporting periods, so holder counts, reported value, and reported shares can be compared over time.