William Blair Investment Management, Llc
Institutional manager — quarterly 13F holdings, Q ending 2026-03-31
Reported value
$30.26B
Q ending 2026-03-31
Prior quarter
$35.85B
Q ending 2025-12-31
Change
-15.6% QoQ · -15.1% YoY
Positions
413
reported holdings
Largest positions
Top 100 of 413 reported positions by value, Q ending 2026-03-31. A manager can hold shares, calls and puts on the same security at once — such positions are listed as separate rows. Type: Shares = common stock, Put/Call = option positions (valued at the underlying), Principal = debt. Tickers link to stock pages where covered.
| Holding | Ticker | Type | Value ▼ | Shares |
|---|---|---|---|---|
| Taiwan Semiconductor Manufac | TSM | Shares | $1.87B | 5.5M |
| Nvidia Corporation | NVDA | Shares | $1.56B | 8.9M |
| Apple Inc | AAPL | Shares | $1.22B | 4.8M |
| Microsoft Corp | MSFT | Shares | $1.07B | 2.9M |
| Alphabet Inc | GOOGL | Shares | $720.2M | 2.5M |
| Broadcom Inc | AVGO | Shares | $681.4M | 2.2M |
| Amazon Com Inc | AMZN | Shares | $658.9M | 3.2M |
| Meta Platforms Inc | META | Shares | $579.6M | 1.0M |
| Mastercard Incorporated | MA | Shares | $530.0M | 1.1M |
| Astrazeneca Plc | Shares | $377.3M | 1.9M | |
| Linde Plc | Shares | $315.5M | 636K | |
| Carlyle Group Inc | CG | Shares | $304.9M | 6.3M |
| Costco Wholesale Corporation | COST | Shares | $301.4M | 302K |
| Itau Unibanco Hldg S A | ITUB | Shares | $265.6M | 31.7M |
| Twist Bioscience Corp | TWST | Shares | $250.4M | 5.3M |
| Servicenow Inc | NOW | Shares | $248.0M | 2.4M |
| Primo Brands Corporation | PRMB | Shares | $245.8M | 13.1M |
| Mueller Inds Inc | MLI | Shares | $233.8M | 2.1M |
| Intuit | INTU | Shares | $230.8M | 534K |
| Monster Beverage Corp New | MNST | Shares | $212.7M | 2.9M |
| Advanced Micro Devices Inc | AMD | Shares | $212.1M | 1.0M |
| Credicorp Ltd | Shares | $211.2M | 623K | |
| Agilent Technologies Inc | A | Shares | $204.7M | 1.8M |
| Oreilly Automotive Inc | ORLY | Shares | $204.0M | 2.2M |
| Bwx Technologies Inc | BWXT | Shares | $200.8M | 982K |
| Transunion | TRU | Shares | $200.0M | 2.9M |
| Onto Innovation Inc | ONTO | Shares | $197.7M | 964K |
| Idexx Labs Inc | IDXX | Shares | $197.6M | 352K |
| Nextpower Inc | NXT | Shares | $195.6M | 1.6M |
| Argenx Se | ARGX | Shares | $194.4M | 266K |
| Cava Group Inc | CAVA | Shares | $193.7M | 2.4M |
| Lattice Semiconductor Corp | LSCC | Shares | $189.6M | 2.0M |
| F5 Inc | FFIV | Shares | $188.0M | 650K |
| Akamai Technologies Inc | AKAM | Shares | $185.9M | 1.6M |
| Cameco Corp | CCJ | Shares | $182.7M | 1.7M |
| Unitedhealth Group Inc | UNH | Shares | $182.2M | 673K |
| Madrigal Pharmaceuticals Inc | MDGL | Shares | $178.3M | 341K |
| Nu Hldgs Ltd | Shares | $176.3M | 12.3M | |
| Globus Med Inc | GMED | Shares | $173.2M | 2.0M |
| C H Robinson Worldwide In | CHRW | Shares | $173.0M | 1.0M |
| Everpure Inc | P | Shares | $170.1M | 2.9M |
| Snowflake Inc | SNOW | Shares | $170.1M | 1.1M |
| Talen Energy Corp | TLN | Shares | $167.7M | 525K |
| Grand Canyon Ed Inc | LOPE | Shares | $166.6M | 980K |
| Everest Group Ltd | Shares | $165.4M | 506K | |
| Halozyme Therapeutics Inc | HALO | Shares | $163.3M | 2.5M |
| Martin Marietta Matls Inc | MLM | Shares | $160.4M | 272K |
| Coherent Corp | COHR | Shares | $159.2M | 668K |
| Curtiss Wright Corp | CW | Shares | $158.1M | 232K |
| Regal Rexnord Corporation | RRX | Shares | $156.8M | 837K |
| Borgwarner Inc | BWA | Shares | $156.5M | 2.9M |
| Ciena Corp | CIEN | Shares | $154.7M | 399K |
| The Baldwin Insurance Grp In | BWIN | Shares | $149.1M | 6.8M |
| Insmed Inc | INSM | Shares | $147.6M | 903K |
| Nvent Elec Plc | Shares | $145.9M | 1.2M | |
| Copart Inc | CPRT | Shares | $145.9M | 4.4M |
| Healthequity Inc | HQY | Shares | $138.7M | 1.7M |
| Carpenter Technology Corp | CRS | Shares | $138.3M | 351K |
| Donaldson Inc | DCI | Shares | $137.1M | 1.6M |
| Amphenol Corp | APH | Shares | $136.1M | 1.1M |
| Lincoln Elec Hldgs Inc | LECO | Shares | $133.2M | 535K |
| Sterling Infrastructure Inc | STRL | Shares | $131.7M | 323K |
| Mercadolibre Inc | MELI | Shares | $129.4M | 75K |
| Bio-Techne Corp | TECH | Shares | $128.7M | 2.5M |
| Clean Harbors Inc | CLH | Shares | $127.0M | 443K |
| Chipotle Mexican Grill Inc | CMG | Shares | $125.2M | 3.9M |
| Reliance Inc | RS | Shares | $122.6M | 403K |
| Power Integrations Inc | POWI | Shares | $121.9M | 2.4M |
| Eagle Matls Inc | EXP | Shares | $119.4M | 630K |
| Dynatrace Inc | DT | Shares | $119.4M | 3.2M |
| Bentley Sys Inc | BSY | Shares | $116.7M | 3.3M |
| Glaukos Corp | GKOS | Shares | $115.6M | 1.1M |
| First Horizon Corporation | FHN | Shares | $115.1M | 5.1M |
| Sharkninja Inc | Shares | $113.7M | 1.1M | |
| Veeva Sys Inc | VEEV | Shares | $113.0M | 643K |
| Doximity Inc | DOCS | Shares | $112.6M | 4.8M |
| Synaptics Inc | SYNA | Shares | $111.1M | 1.6M |
| National Vision Hldgs Inc | EYE | Shares | $109.4M | 4.2M |
| Planet Fitness Master Issuer | PLNT | Shares | $108.0M | 1.5M |
| Diebold Nixdorf Inc | DBD | Shares | $107.6M | 1.4M |
| Freshpet Inc | FRPT | Shares | $106.9M | 1.8M |
| Millicom Intl Cellular S A | Shares | $105.3M | 1.4M | |
| Krystal Biotech Inc | KRYS | Shares | $105.2M | 407K |
| Garrett Motion Inc | GTX | Shares | $104.7M | 5.8M |
| Verisk Analytics Inc | VRSK | Shares | $103.9M | 548K |
| Littelfuse Inc | LFUS | Shares | $103.4M | 305K |
| Appfolio Inc | APPF | Shares | $101.5M | 643K |
| Casella Waste Sys Inc | CWST | Shares | $99.7M | 1.3M |
| Churchill Downs Inc | CHDN | Shares | $98.2M | 1.1M |
| National Bk Hldgs Corp | NBHC | Shares | $96.9M | 2.5M |
| Novanta Inc | NOVT | Shares | $92.5M | 783K |
| Birkenstock Holding Plc | Shares | $92.3M | 2.6M | |
| Alignment Healthcare Inc | ALHC | Shares | $91.9M | 5.2M |
| Pool Corp | POOL | Shares | $91.5M | 452K |
| Stepstone Group Inc | STEP | Shares | $91.4M | 1.9M |
| Advanced Drain Sys Inc Del | WMS | Shares | $89.9M | 656K |
| Kennametal Inc | KMT | Shares | $89.7M | 2.5M |
| Guardant Health Inc | GH | Shares | $87.9M | 951K |
| Old Natl Bancorp Ind | ONB | Shares | $86.1M | 3.9M |
| Fabrinet | Shares | $86.0M | 165K |
Values as reported in public regulatory filings (USD); holdings are reported quarterly, up to 45 days after quarter end, and may contain reporting errors. Nothing here is investment advice.