BLAIR WILLIAM & CO/IL — 13F Holdings & Portfolio
CIK 902367 · latest 13F-HR filed 2026-05-08
BLAIR WILLIAM & CO/IL manages $34.90B in 13F-reported U.S. long-equity assets across 1,922 reported positions as of its 2026-03-31 13F-HR filing. Its largest disclosed positions are AAPL (4.31%), MSFT (3.71%), AMZN (3.62%). Quarter over quarter (versus its 2025-12-31 filing) the fund opened 155 new positions, exited 100, added to 666, and trimmed 677.
AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.
$34.90B
Long-equity book
1,922
Distinct positions
2026-03-31
Filed 2026-05-08
+155 / −100 / ↑666 / ↓677
vs 2025-12-31
| Name | Title / Status | Ownership | Type |
|---|
Top Adds (vs prior quarter)
- INVESCO EXCHANGE TRADED FD T$217.2M +206.1%
- GE VERNOVA INC$153.8M +36.1%
- VANGUARD INTL EQUITY INDEX F$113.6M +57.0%
- QUANTA SVCS INC$90.1M +265.9%
- COSTCO WHOLESALE CORPORATION$70.0M +15.6%
Top Trims
- MICROSOFT CORP-$433.8M -25.1%
- SERVICENOW INC-$151.0M -44.5%
- IDEXX LABS INC-$145.7M -21.5%
- WORKDAY INC-$145.0M -81.4%
- APPLOVIN CORP-$142.7M -71.9%
New Positions
- ASTRAZENECA PLC$19.8M
- SILICON MOTION TECHNOLOGY CO$11.6M
- GUARDANT HEALTH INC$9.6M
- SOLID BIOSCIENCES INC$4.7M
- RAYONIER INC$2.7M
Exited Positions
- DYNAVAX TECHNOLOGIES CORP$27.4M
- ASTRAZENECA PLC$19.4M
- CYBERARK SOFTWARE LTD$14.5M
- EXACT SCIENCES CORP$13.1M
- QUALYS INC$6.4M
Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).
| # | Issuer | Symbol | CUSIP | Value | Weight | Shares | Type |
|---|---|---|---|---|---|---|---|
| 1 | APPLE INC | AAPL | 037833100 | $1.51B | 4.31% | 5,930,914 | SH |
| 2 | MICROSOFT CORP | MSFT | 594918104 | $1.29B | 3.71% | 3,498,110 | SH |
| 3 | AMAZON COM INC | AMZN | 023135106 | $1.26B | 3.62% | 6,057,938 | SH |
| 4 | NVIDIA CORPORATION | NVDA | 67066G104 | $946.6M | 2.71% | 5,427,875 | SH |
| 5 | ALPHABET INC | GOOG | 02079K107 | $870.8M | 2.50% | 3,035,765 | SH |
| 6 | ALPHABET INC | GOOGL | 02079K305 | $700.5M | 2.01% | 2,436,117 | SH |
| 7 | JPMORGAN CHASE & CO | JPM | 46625H100 | $678.7M | 1.94% | 2,307,253 | SH |
| 8 | GE VERNOVA INC | GEV | 36828A101 | $580.1M | 1.66% | 664,603 | SH |
| 9 | VISA INC | V | 92826C839 | $557.5M | 1.60% | 1,844,583 | SH |
| 10 | STATE STR SPDR S&P 500 ETF T | SPY | 78462F103 | $549.7M | 1.58% | 845,294 | SH |
| 11 | IDEXX LABS INC | IDXX | 45168D104 | $531.7M | 1.52% | 946,336 | SH |
| 12 | COSTCO WHOLESALE CORPORATION | COST | 22160K105 | $519.4M | 1.49% | 521,277 | SH |
| 13 | MASTERCARD INCORPORATED | MA | 57636Q104 | $461.4M | 1.32% | 923,405 | SH |
| 14 | META PLATFORMS INC | META | 30303M102 | $412.9M | 1.18% | 721,720 | SH |
| 15 | FASTENAL CO | FAST | 311900104 | $342.1M | 0.98% | 7,373,707 | SH |
| 16 | INVESCO EXCHANGE TRADED FD T | RSP | 46137V357 | $322.5M | 0.92% | 1,680,604 | SH |
| 17 | AMPHENOL CORP | APH | 032095101 | $318.4M | 0.91% | 2,520,319 | SH |
| 18 | ISHARES TR | IVV | 464287200 | $317.4M | 0.91% | 485,839 | SH |
| 19 | VANGUARD INTL EQUITY INDEX F | VEU | 922042775 | $313.1M | 0.90% | 4,168,625 | SH |
| 20 | ELI LILLY & CO | LLY | 532457108 | $298.0M | 0.85% | 324,018 | SH |
| 21 | WALMART INC | WMT | 931142103 | $295.1M | 0.85% | 2,374,282 | SH |
| 22 | BWX TECHNOLOGIES INC | BWXT | 05605H100 | $294.1M | 0.84% | 1,438,125 | SH |
| 23 | ABBVIE INC | ABBV | 00287Y109 | $290.2M | 0.83% | 1,334,109 | SH |
| 24 | BROADCOM INC | AVGO | 11135F101 | $284.2M | 0.81% | 918,328 | SH |
| 25 | STRYKER CORPORATION | SYK | 863667101 | $278.5M | 0.80% | 847,701 | SH |
| 26 | INTERCONTINENTAL EXCHANGE IN | ICE | 45866F104 | $250.6M | 0.72% | 1,593,628 | SH |
| 27 | HOME DEPOT INC | HD | 437076102 | $250.4M | 0.72% | 761,419 | SH |
| 28 | VANGUARD TAX-MANAGED FDS | VEA | 921943858 | $247.5M | 0.71% | 3,862,086 | SH |
| 29 | DANAHER CORP DEL | DHR | 235851102 | $245.9M | 0.70% | 1,296,804 | SH |
| 30 | PROGRESSIVE CORP | PGR | 743315103 | $241.8M | 0.69% | 1,219,749 | SH |
| 31 | VANGUARD INDEX FDS | VOO | 922908363 | $237.5M | 0.68% | 397,380 | SH |
| 32 | BERKSHIRE HATHAWAY INC DEL | BRK.B | 084670702 | $237.4M | 0.68% | 495,322 | SH |
| 33 | UBER TECHNOLOGIES INC | UBER | 90353T100 | $237.3M | 0.68% | 3,299,596 | SH |
| 34 | JOHNSON & JOHNSON | JNJ | 478160104 | $233.6M | 0.67% | 955,632 | SH |
| 35 | ECOLAB INC | ECL | 278865100 | $230.5M | 0.66% | 866,411 | SH |
| 36 | VANGUARD INDEX FDS | VTV | 922908744 | $228.8M | 0.66% | 1,165,912 | SH |
| 37 | WATSCO INC | WSO | 942622200 | $212.0M | 0.61% | 582,700 | SH |
| 38 | AMERICAN EXPRESS CO | AXP | 025816109 | $209.9M | 0.60% | 693,767 | SH |
| 39 | PALO ALTO NETWORKS INC | PANW | 697435105 | $209.2M | 0.60% | 1,304,858 | SH |
| 40 | INTUITIVE SURGICAL INC | ISRG | 46120E602 | $196.0M | 0.56% | 425,228 | SH |
| 41 | TRANSDIGM GROUP INC | TDG | 893641100 | $192.7M | 0.55% | 166,248 | SH |
| 42 | SERVICENOW INC | NOW | 81762P102 | $188.3M | 0.54% | 1,800,988 | SH |
| 43 | VEEVA SYS INC | VEEV | 922475108 | $187.5M | 0.54% | 1,067,576 | SH |
| 44 | BOEING CO | BA | 097023105 | $183.5M | 0.53% | 922,102 | SH |
| 45 | INVESCO QQQ TR | QQQ | 46090E103 | $179.5M | 0.51% | 311,016 | SH |
| 46 | EVERPURE INC | P | 74624M102 | $172.3M | 0.49% | 2,918,046 | SH |
| 47 | NETFLIX INC. | NFLX | 64110L106 | $169.6M | 0.49% | 1,763,451 | SH |
| 48 | SPDR GOLD TR | GLD | 78463V107 | $166.4M | 0.48% | 386,735 | SH |
| 49 | CINTAS CORP | CTAS | 172908105 | $164.7M | 0.47% | 973,553 | SH |
| 50 | EXXON MOBIL CORP | XOM | 30231G102 | $160.6M | 0.46% | 946,386 | SH |
| Period | Filed | AUM | Holdings | Accession |
|---|---|---|---|---|
| 2026-03-31 | 2026-05-08 | $34.90B | 1,922 | 0001104659-26-057897 |
| 2025-12-31 | 2026-02-17 | $37.26B | 1,920 | 0001104659-26-015563 |