IDEXX LABORATORIES INC (IDXX) Institutional Ownership Changes & 13F Activity

IDEXX LABORATORIES INC (IDXX) institutional ownership data tracks hedge funds, asset managers, and other institutional investors based on recent SEC 13F filings (Q1 2026). This page analyzes institutional buying and selling activity, new holdings, and sold-out positions among tracked filers. Notable filers include Fundsmith, Polen Capital Management, Fundsmith Investment Services, Renaissance Technologies LLC, and Parnassus Endeavor Fund.

Portfolio quarterNameTypeQuantityRemainingReported stock balance
Q1 2025Durable Capital PartnersBuy156,727364,757$153,179,702
Q1 2025Lountzis Asset ManagementBuy32,69632,696$14,189,737
Q1 2025FundsmithSell-14,5242,648,331$1,112,166,603
Q1 2025Parnassus Endeavor FundSell-11,69436,653$15,392,427
Q1 2025Fundsmith Investment ServicesSell-10,649854,359$358,788,062
Q1 2025Jensen Investment ManagementSell-8308,190$3,439,391
Q1 2025Sequoia Financial AdvisorsBuy2521,937$813,368
Q1 2025Mairs & Power Growth FundSell-962,306$968,405
Q4 2024Renaissance Technologies LLCSell-10,70025,000$10,336,000
Q4 2024FundsmithSell-1,3072,662,855$1,100,930,771
Q4 2024Jensen Investment ManagementBuy9309,020$3,729,229
Q4 2024Parnassus Endeavor FundSell-63648,347$19,988,584
Q4 2024Mairs & Power Growth FundSell-1002,402$993,083
Q4 2024Sequoia Financial AdvisorsBuy981,685$696,573
Q3 2024Renaissance Technologies LLCBuy15,09635,700$18,036,354
Q3 2024Jensen Investment ManagementBuy2,9708,090$4,087,230
Q3 2024Fundsmith Investment ServicesBuy1,846865,008$437,019,342
Q3 2024FundsmithBuy9702,664,162$1,345,987,926
Q3 2024Sequoia Financial AdvisorsSell-21,587$801,694
Q2 2024FundsmithSell-51,5702,663,192$1,297,507,142
Q2 2024Fundsmith Investment ServicesBuy42,281863,162$420,532,526
Q2 2024Renaissance Technologies LLCSell-13,20020,604$10,038,269
Q2 2024Jensen Investment ManagementBuy5,1205,120$2,494,464
Q2 2024Sequoia Financial AdvisorsBuy1171,589$774,074
Q2 2024Mairs & Power Growth FundSell-802,502$1,218,974
Q1 2024Renaissance Technologies LLCSell-91,00033,804$18,252
Q1 2024Torray FundBuy58,13458,518$207,333
Q1 2024FundsmithSell-14,1552,714,762$1,465,781,447
Q1 2024Fundsmith Investment ServicesBuy2,262820,881$443,218,278
Q1 2024Sequoia Financial AdvisorsSell-5071,472$794,680

Frequently asked questions about IDXX activity

  • Which institutional owners are buying IDXX?

    Institutional owners buying IDXX include investors who have either initiated new positions or increased their existing holdings based on recent SEC 13F filings. The activity table above highlights which funds added shares in the latest reporting periods and how their positions changed over time.

  • What does "buy" mean in IDXX activity?

    "Buy" means an investor increased their reported position in IDXX compared to the prior reporting period. This reflects growing exposure to IDEXX LABORATORIES INC (IDXX) rather than necessarily a brand-new position (though new positions also appear as buys when prior quantity was zero).

  • Is institutional interest in IDXX increasing?

    Institutional interest in IDXX can be assessed by comparing the number of tracked funds adding or increasing positions versus those trimming or exiting across the periods shown. A higher number of additions typically signals increasing participation among large filers, but it should be read alongside position sizes and the full table.

Related IDXX insights