Institutional manager
WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC
Holds positions in 94 of the S&P 500, worth $13.8bn as reported for the quarter ended 31-mar-2026.
Positions held94of 488 index companies covered
Reported value$13.8bnS&P 500 positions only
Top ten weight67%how concentrated the book is
Filing entities1single filer
Largest positions
The 60 biggest by reported value, of 94 held. The rest are smaller than every one of these.
Taiwan Semiconductor ManufacturingTSM5.5m$1.87bnNvidiaNVDA8.9m$1.56bnInformation TechnologyApple Inc.AAPL4.8m$1.22bnInformation TechnologyMicrosoftMSFT2.9m$1.07bnInformation TechnologyAlphabet Inc. (Class A)GOOGL2.5m$721mCommunication ServicesBroadcomAVGO2.2m$681mInformation TechnologyAmazonAMZN3.2m$659mConsumer DiscretionaryMeta PlatformsMETA1.0m$580mCommunication ServicesMastercardMA1.1m$530mFinancialsLinde plcLIN636,338$315mMaterialsCostcoCOST302,468$301mConsumer StaplesServiceNowNOW2.4m$248mInformation TechnologyIntuitINTU533,736$231mInformation TechnologyMonster BeverageMNST2.9m$213mConsumer StaplesAdvanced Micro DevicesAMD1.0m$212mInformation TechnologyAgilent TechnologiesA1.8m$205mHealth CareO'Reilly AutomotiveORLY2.2m$204mConsumer DiscretionaryIdexx LaboratoriesIDXX351,621$198mHealth CareF5, Inc.FFIV649,948$188mInformation TechnologyAkamai TechnologiesAKAM1.6m$186mInformation TechnologyUnitedHealth GroupUNH673,263$182mHealth CareC.H. RobinsonCHRW1.0m$173mIndustrialsEverest GroupEG506,166$165mFinancialsMartin Marietta MaterialsMLM272,392$160mMaterialsCoherent Corp.COHR668,137$159mInformation TechnologyCienaCIEN398,579$155mInformation TechnologyCopartCPRT4.4m$146mIndustrialsAmphenolAPH1.1m$136mInformation TechnologyBio-TechneTECH2.5m$129mHealth CareChipotle Mexican GrillCMG3.9m$125mConsumer DiscretionaryVeeva SystemsVEEV643,325$113mHealth CareVerisk AnalyticsVRSK547,504$104mIndustrialsCasey'sCASY118,098$86mConsumer StaplesTexas InstrumentsTXN424,195$82mInformation TechnologyTyler TechnologiesTYL215,748$74mInformation TechnologyLOUISIANA-PACIFIC CORPLPX596,108$43mInsulet CorporationPODD139,130$29mHealth CareMarriott InternationalMAR84,631$28mConsumer DiscretionaryLilly (Eli)LLY29,051$27mHealth CareMotorola SolutionsMSI51,961$23mInformation TechnologyPalo Alto NetworksPANW130,453$21mInformation TechnologyLumentumLITE26,579$19mInformation TechnologyVertex PharmaceuticalsVRTX39,547$18mHealth CareLam ResearchLRCX79,447$17mInformation TechnologyAvery DennisonAVY84,465$15mMaterialsDexcomDXCM195,431$12mHealth CareApplied MaterialsAMAT34,940$12mInformation TechnologyWest Pharmaceutical ServicesWST39,725$10mHealth CareMarvell TechnologyMRVL99,542$10mInformation TechnologyCencoraCOR28,475$9mHealth CareOracle CorporationORCL55,726$8mInformation TechnologyWalmartWMT62,950$8mConsumer StaplesIntuitive SurgicalISRG15,142$7mHealth CareProgressive CorporationPGR30,797$6mFinancialsJPMorgan ChaseJPM20,562$6mFinancialsHumanaHUM34,577$6mHealth CareSalesforceCRM28,986$5mInformation TechnologyTJX CompaniesTJX33,796$5mConsumer DiscretionaryBlackstone Inc.BX46,877$5mFinancialsNetflixNFLX53,276$5mCommunication Services
What this page is not
Positions in the companies this site covers, from 13F filings, which report US listed, long, US custodied holdings. A manager's real book is larger than this in every case: anything outside the index, outside US custody, held through derivatives, or below its reporting obligation is not here.