Funds › William Blair & Co
William Blair & Co
13F for Q3 2026, filed Nov 10, 2026. 1,951 positions worth $38.6B.Managers with more than $100 million in US-listed stocks list their holdings each quarter, within 45 days of quarter end. Long positions only: no short sales or cash.
Latest report
Q3 2026
filed Nov 10, 2026
Reported value
$38.6B
+$204.9M (0.5%) vs Q2 2026
Positions
1,951
1,977 in Q2 2026
Top 10 share
27.9%
of reported value
CheckedEach line's price per share is checked against other managers' reports of the same stock. Unit mix-ups are corrected. Reports no fix can rescue are left out.
Clean
prices match other managers' reports
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Holdings, Q3 2026
Largest first. Common shares only; puts and calls are under All positions.
| # | The fund's own figures at the end of the quarter. A report can be up to 45 days old when it is filed. Options and bonds are not counted here. | Filing | ||||
|---|---|---|---|---|---|---|
| 1 | AAPL Apple Inc. | 5.70M | $1.9B | 4.9% | -0.5% | 13F ↗ |
| 2 | MSFT Microsoft Corporation | 3.41M | $1.7B | 4.5% | -1.1% | 13F ↗ |
| 3 | AMZN Amazon.com, Inc. | 5.73M | $1.4B | 3.7% | -2.5% | 13F ↗ |
| 4 | NVDA NVIDIA Corporation | 5.41M | $1.2B | 3.2% | +0.6% | 13F ↗ |
| 5 | GOOG Alphabet Inc. Class C | 2.90M | $988.7M | 2.6% | -1.8% | 13F ↗ |
| 6 | GOOGL Alphabet Inc. Class A | 2.35M | $808.5M | 2.1% | -2.2% | 13F ↗ |
| 7 | JPM JPMorgan Chase & Co. | 2.27M | $750.2M | 1.9% | -0.1% | 13F ↗ |
| 8 | V Visa Inc. | 1.81M | $649.7M | 1.7% | -1.8% | 13F ↗ |
| 9 | SPY State Street SPDR S&P 500 ETF Trust · Trust units | 843,045 | $642.9M | 1.7% | -0.6% | 13F ↗ |
| 10 | GEV GE Vernova Inc. | 642,163 | $610.4M | 1.6% | -2.7% | 13F ↗ |
| 11 | COST Costco Wholesale Corporation | 510,537 | $464.8M | 1.2% | -2.7% | 13F ↗ |
| 12 | MA Mastercard Incorporated | 815,550 | $449.8M | 1.2% | -3.2% | 13F ↗ |
| 13 | PANW Palo Alto Networks, Inc. | 1.12M | $445.4M | 1.2% | -8.6% | 13F ↗ |
| 14 | IDXX IDEXX Laboratories, Inc. | 847,318 | $442.5M | 1.1% | -7.8% | 13F ↗ |
| 15 | Invesco Exchange Traded Fd T S&P500 Eql Wgt | 2.12M | $441.3M | 1.1% | +7.0% | 13F ↗ |
| 16 | LLY Eli Lilly and Company | 362,756 | $419.7M | 1.1% | +4.5% | 13F ↗ |
| 17 | APH Amphenol Corporation | 4.88M | $411.4M | 1.1% | -2.6% | 13F ↗ |
| 18 | META Meta Platforms, Inc. | 558,258 | $404.8M | 1.0% | -16.8% | 13F ↗ |
| 19 | P Everpure, Inc. | 3.08M | $402.7M | 1.0% | +1.0% | 13F ↗ |
| 20 | Vanguard International Equity Index F Allwrld Ex Us | 4.54M | $376.5M | 1.0% | +1.3% | 13F ↗ |
| 21 | iShares Tr Core S&P500 Etf | 480,886 | $368.3M | 1.0% | -0.8% | 13F ↗ |
| 22 | FAST Fastenal Company | 7.34M | $363.4M | 0.9% | -0.9% | 13F ↗ |
| 23 | AVGO Broadcom Inc. | 1.01M | $353.2M | 0.9% | +8.2% | 13F ↗ |
| 24 | ANET Arista Networks, Inc. | 1.66M | $337.6M | 0.9% | +3.3% | 13F ↗ |
| 25 | MU Micron Technology, Inc. | 313,635 | $334.1M | 0.9% | -0.7% | 13F ↗ |
| 26 | ABBV AbbVie Inc. | 1.28M | $333.9M | 0.9% | -0.9% | 13F ↗ |
| 27 | Vanguard Index Fds S&P 500 Etf Shs | 455,353 | $319.1M | 0.8% | +8.6% | 13F ↗ |
| 28 | Vanguard Tax-Managed Fds | 4.28M | $302.2M | 0.8% | -0.2% | 13F ↗ |
| 29 | NOW ServiceNow, Inc. | 2.17M | $291.0M | 0.8% | -3.1% | 13F ↗ |
| 30 | Invesco Qqq Tr | 385,296 | $285.0M | 0.7% | +7.3% | 13F ↗ |
| 31 | Vanguard Index Fds Mrngstr Val Etf | 1.27M | $274.1M | 0.7% | +2.9% | 13F ↗ |
| 32 | CRWD CrowdStrike Holdings, Inc. | 1.01M | $266.7M | 0.7% | -7.5% | 13F ↗ |
| 33 | JNJ Johnson & Johnson | 957,624 | $253.5M | 0.7% | +0.1% | 13F ↗ |
| 34 | Vanguard Index Fds Mrngstr Ttl Stk | 656,240 | $245.6M | 0.6% | +24.2% | 13F ↗ |
| 35 | WMT Walmart Inc. | 2.30M | $238.6M | 0.6% | +1.1% | 13F ↗ |
| 36 | BRK-B Berkshire Hathaway Inc. Class B | 478,690 | $238.4M | 0.6% | -1.0% | 13F ↗ |
| 37 | ECL Ecolab Inc. | 843,745 | $231.7M | 0.6% | -1.2% | 13F ↗ |
| 38 | AXP American Express Company | 676,381 | $205.7M | 0.5% | -0.6% | 13F ↗ |
| 39 | VEEV Veeva Systems Inc. | 717,633 | $204.8M | 0.5% | -4.4% | 13F ↗ |
| 40 | iShares Tr Etf | 730,667 | $203.0M | 0.5% | +4.2% | 13F ↗ |
| 41 | CTAS Cintas Corporation | 1.04M | $203.0M | 0.5% | -2.2% | 13F ↗ |
| 42 | DHR Danaher Corporation | 901,012 | $199.6M | 0.5% | -7.2% | 13F ↗ |
| 43 | PGR Progressive Corporation | 946,776 | $196.3M | 0.5% | -8.4% | 13F ↗ |
| 44 | HD Home Depot, Inc. | 683,829 | $194.5M | 0.5% | -2.0% | 13F ↗ |
| 45 | BWXT BWX Technologies, Inc. | 1.40M | $191.5M | 0.5% | -10.2% | 13F ↗ |
| 46 | SYK Stryker Corporation | 640,269 | $176.3M | 0.5% | -6.4% | 13F ↗ |
| 47 | TDG Transdigm Group Incorporated | 157,259 | $170.2M | 0.4% | -4.7% | 13F ↗ |
| 48 | Vanguard Specialized Funds Div App Etf | 722,836 | $168.6M | 0.4% | +0.6% | 13F ↗ |
| 49 | ISRG Intuitive Surgical, Inc. | 408,196 | $166.0M | 0.4% | +2.7% | 13F ↗ |
| 50 | ICE Intercontinental Exchange Inc. | 1.09M | $165.3M | 0.4% | -15.3% | 13F ↗ |
Showing the top 50 of 1,951 positions. Premium lists every position, plus puts and calls.
Changes since Q2 2026
102 new, 662 added to, 947 trimmed, 128 exited, 240 unchanged. By estimated dollars.
New positions (102)
| XOM ExxonMobil Holdings Corporation | 907,513 | New | $147.7M |
| FPS Forgent Power Solutions, Inc. | 961,945 | New | $36.0M |
| SKHY SK hynix Inc. · American Deposit | 75,482 | New | $13.9M |
| OKE ONEOK, Inc. | 133,484 | New | $11.4M |
| Dfa Invt Dimensions Group In U.S. Core Eqty 1 | 62,072 | New | $5.1M |
| Innovator Etfs Trust Equity Dual 15 B | 71,425 | New | $1.4M |
| HNGE Hinge Health, Inc. | 11,591 | New | $1.1M |
| TEVA Teva Pharmaceutical Industries Limited | 27,209 | New | $1.1M |
| ARHS Arhaus, Inc. | 108,391 | New | $1.0M |
| SPSC SPS Commerce, Inc. | 11,754 | New | $969.0K |
Added to (662)
| Vanguard Index Fds Mrngstr Ttl Stk | 656,240 | +24.2% | $47.8M |
| SPCX Space Exploration Technologies Corp. | 367,098 | +517% | $46.4M |
| AXON Axon Enterprise, Inc. | 210,865 | +75.3% | $38.3M |
| RGEN Repligen Corporation | 190,031 | +7004% | $36.0M |
| MCO Moody's Corporation | 142,279 | +124% | $35.7M |
| Invesco Exchange Traded Fd T S&P500 Eql Wgt | 2.12M | +7.0% | $28.9M |
| AVGO Broadcom Inc. | 1.01M | +8.2% | $26.7M |
| Vanguard Index Fds S&P 500 Etf Shs | 455,353 | +8.6% | $25.2M |
| iShares Inc Core Msci Emkt | 616,037 | +86.6% | $23.2M |
| WAY Waystar Holding Corp. | 1.05M | +472% | $21.9M |
Trimmed (947)
| META Meta Platforms, Inc. | 558,258 | -16.8% | -$81.7M |
| PANW Palo Alto Networks, Inc. | 1.12M | -8.6% | -$41.9M |
| WSO Watsco, Inc. | 438,016 | -22.3% | -$38.1M |
| IDXX IDEXX Laboratories, Inc. | 847,318 | -7.8% | -$37.2M |
| AMZN Amazon.com, Inc. | 5.73M | -2.5% | -$36.1M |
| UBER Uber Technologies, Inc. | 2.29M | -18.1% | -$34.7M |
| ICE Intercontinental Exchange Inc. | 1.09M | -15.3% | -$29.9M |
| ROL Rollins, Inc. | 591,423 | -60.0% | -$26.7M |
| BA Boeing Company | 758,899 | -13.6% | -$22.2M |
| RBA RB Global, Inc. | 257,873 | -51.0% | -$21.9M |
Exited (128)
| PTRN Pattern Group Inc. | 703,580 | Exited | -$17.7M |
| Oneok Inc | 140,323 | Exited | -$12.2M |
| Electronic Arts Inc | 9,367 | Exited | -$1.9M |
| Avalonbay Communities Inc Reit | 9,127 | Exited | -$1.7M |
| HHS Harte Hanks, Inc. | 660,845 | Exited | -$1.4M |
| Warner Bros Discovery Inc | 45,717 | Exited | -$1.2M |
| BCO Brinks Company | 11,685 | Exited | -$1.1M |
| Re/Max Holdings Inc | 100,627 | Exited | -$992.2K |
| BKSY BlackSky Technology Inc. | 34,630 | Exited | -$966.9K |
| Teva Pharmaceutical Industries Ltd ADR | 26,635 | Exited | -$902.4K |
The 10 largest of each, by estimated dollars: shares changed times the later report's price. Index tracking, splits and mergers move positions too.
All positions
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Reported value by quarter
Value and number of positions at the end of each quarter.
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Largest positions in earlier quarters
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Ten largest positions
By value, Q3 2026.
Filings
| Filing | ||||||
|---|---|---|---|---|---|---|
| Q3 2026 | Nov 10, 2026 | 13F-HR | 1,971 | $38.6B | Current | SEC ↗ |
| Q2 2026 | Aug 11, 2026 | 13F-HR | 1,998 | $38.4B | Current | SEC ↗ |
| Q1 2026 | May 8, 2026 | 13F-HR | 1,922 | $34.9B | Current | SEC ↗ |
| Q4 2025 | Feb 17, 2026 | 13F-HR | 1,867 | $37.3B | Current | SEC ↗ |
| Q3 2025 | Nov 12, 2025 | 13F-HR | 1,844 | $37.6B | Current | SEC ↗ |
| Q2 2025 | Jul 24, 2025 | 13F-HR | 1,824 | $36.0B | Current | SEC ↗ |
| Q1 2025 | May 9, 2025 | 13F-HR | 1,801 | $33.2B | Current | SEC ↗ |
Most recent first, up to 80. An amendment can replace a report or add holdings to it. All 13F filings
Information, not investment advice. Values are the fund's own figures at quarter end; a report can be up to 45 days old when filed. Disclaimer