Funds › William Blair Investment Management, LLC
William Blair Investment Management, LLC
13F for Q3 2026, filed Nov 6, 2026. 399 positions worth $30.8B.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 6, 2026
Reported value
$30.8B
−$2.4B (7.3%) vs Q2 2026
Positions
399
403 in Q2 2026
Top 10 share
31.0%
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 | TSM Taiwan Semiconductor Manufacturing Company Ltd. | 4.59M | $2.1B | 6.8% | -7.1% | 13F ↗ |
| 2 | NVDA NVIDIA Corporation | 8.12M | $1.9B | 6.0% | -5.5% | 13F ↗ |
| 3 | GOOGL Alphabet Inc. Class A | 3.61M | $1.2B | 4.0% | +13.1% | 13F ↗ |
| 4 | AAPL Apple Inc. | 3.02M | $1.0B | 3.3% | -7.3% | 13F ↗ |
| 5 | MSFT Microsoft Corporation | 1.71M | $877.8M | 2.8% | -16.5% | 13F ↗ |
| 6 | AVGO Broadcom Inc. | 1.98M | $696.5M | 2.3% | -3.5% | 13F ↗ |
| 7 | META Meta Platforms, Inc. | 806,777 | $585.1M | 1.9% | -15.1% | 13F ↗ |
| 8 | AMD Advanced Micro Devices, Inc. | 783,197 | $479.1M | 1.6% | +2.6% | 13F ↗ |
| 9 | MA Mastercard Incorporated | 707,647 | $390.2M | 1.3% | -22.9% | 13F ↗ |
| 10 | P Everpure, Inc. | 2.55M | $333.4M | 1.1% | -26.2% | 13F ↗ |
| 11 | AMZN Amazon.com, Inc. | 1.33M | $332.1M | 1.1% | -32.9% | 13F ↗ |
| 12 | AMAT Applied Materials, Inc. | 606,347 | $310.1M | 1.0% | +21.8% | 13F ↗ |
| 13 | TWST Twist Bioscience Corporation | 1.45M | $281.0M | 0.9% | -33.1% | 13F ↗ |
| 14 | CG The Carlyle Group Inc. | 6.82M | $270.5M | 0.9% | +15.3% | 13F ↗ |
| 15 | GE GE Aerospace | 854,907 | $267.0M | 0.9% | +8.1% | 13F ↗ |
| 16 | BAP Credicorp Ltd. | 699,385 | $265.7M | 0.9% | +11.9% | 13F ↗ |
| 17 | SNOW Snowflake Inc. | 781,249 | $265.3M | 0.9% | -13.3% | 13F ↗ |
| 18 | APH Amphenol Corporation | 3.09M | $260.3M | 0.8% | +0.6% | 13F ↗ |
| 19 | STX Seagate Technology Holdings PLC | 276,990 | $255.5M | 0.8% | +45.1% | 13F ↗ |
| 20 | MLI Mueller Industries, Inc. | 4.07M | $246.8M | 0.8% | +2.5% | 13F ↗ |
| 21 | FFIV F5, Inc. | 546,951 | $243.5M | 0.8% | -6.7% | 13F ↗ |
| 22 | TEVA Teva Pharmaceutical Industries Limited | 6.12M | $242.3M | 0.8% | New | 13F ↗ |
| 23 | RGEN Repligen Corporation | 1.24M | $239.0M | 0.8% | +57.7% | 13F ↗ |
| 24 | MU Micron Technology, Inc. | 224,405 | $239.0M | 0.8% | +1496% | 13F ↗ |
| 25 | ARGX argenx SE · ADR | 247,401 | $237.2M | 0.8% | -6.5% | 13F ↗ |
| 26 | CRWD CrowdStrike Holdings, Inc. | 890,794 | $235.8M | 0.8% | -20.9% | 13F ↗ |
| 27 | DT Dynatrace, Inc. | 3.87M | $223.7M | 0.7% | +0.4% | 13F ↗ |
| 28 | BWA BorgWarner Inc. | 3.71M | $223.2M | 0.7% | -1.9% | 13F ↗ |
| 29 | PRMB Primo Brands Corporation · Common Stocks | 11.23M | $213.9M | 0.7% | -1.7% | 13F ↗ |
| 30 | ESTC Elastic N.V. | 2.32M | $212.3M | 0.7% | New | 13F ↗ |
| 31 | TLN Talen Energy Corporation | 677,759 | $211.9M | 0.7% | +36.2% | 13F ↗ |
| 32 | A Agilent Technologies, Inc. | 1.23M | $211.2M | 0.7% | -4.8% | 13F ↗ |
| 33 | LIN Linde plc | 437,021 | $207.4M | 0.7% | -13.5% | 13F ↗ |
| 34 | ONTO Onto Innovation Inc. | 652,188 | $200.8M | 0.7% | -2.0% | 13F ↗ |
| 35 | ITUB Itau Unibanco Banco Holding SA · ADR | 21.27M | $181.4M | 0.6% | -24.8% | 13F ↗ |
| 36 | HALO Halozyme Therapeutics, Inc. | 1.62M | $178.5M | 0.6% | -35.6% | 13F ↗ |
| 37 | UNH UnitedHealth Group Incorporated | 484,420 | $177.8M | 0.6% | -7.4% | 13F ↗ |
| 38 | NOW ServiceNow, Inc. | 1.32M | $176.5M | 0.6% | -15.1% | 13F ↗ |
| 39 | KRYS Krystal Biotech, Inc. | 520,925 | $173.2M | 0.6% | -8.6% | 13F ↗ |
| 40 | EG Everest Group, Ltd. | 471,187 | $172.1M | 0.6% | -1.8% | 13F ↗ |
| 41 | MDGL Madrigal Pharmaceuticals, Inc. | 337,035 | $169.9M | 0.6% | +4.0% | 13F ↗ |
| 42 | MANH Manhattan Associates, Inc. | 847,546 | $168.4M | 0.5% | +25.5% | 13F ↗ |
| 43 | APPF AppFolio, Inc. | 836,167 | $167.7M | 0.5% | +15.8% | 13F ↗ |
| 44 | GH Guardant Health, Inc. | 937,974 | $167.3M | 0.5% | -28.5% | 13F ↗ |
| 45 | VSH Vishay Intertechnology, Inc. | 5.12M | $166.8M | 0.5% | +248% | 13F ↗ |
| 46 | CW Curtiss-Wright Corporation | 305,868 | $166.3M | 0.5% | -3.6% | 13F ↗ |
| 47 | COST Costco Wholesale Corporation | 179,618 | $163.5M | 0.5% | -9.9% | 13F ↗ |
| 48 | IDXX IDEXX Laboratories, Inc. | 306,107 | $159.8M | 0.5% | +2.7% | 13F ↗ |
| 49 | CNQ Canadian Natural Resources Limited | 3.35M | $157.7M | 0.5% | -7.8% | 13F ↗ |
| 50 | AKAM Akamai Technologies, Inc. | 1.46M | $155.5M | 0.5% | -4.8% | 13F ↗ |
Showing the top 50 of 399 positions. Premium lists every position, plus puts and calls.
Changes since Q2 2026
46 new, 104 added to, 245 trimmed, 50 exited, 4 unchanged. By estimated dollars.
New positions (46)
| TEVA Teva Pharmaceutical Industries Limited | 6.12M | New | $242.3M |
| ESTC Elastic N.V. | 2.32M | New | $212.3M |
| MBGL Mobility Global Inc. | 5.29M | New | $90.7M |
| PCOR Procore Technologies, Inc. | 1.68M | New | $86.9M |
| SGI Somnigroup International Inc. | 1.13M | New | $70.0M |
| TWLO Twilio Inc. | 215,683 | New | $63.1M |
| MRX Marex Group Limited | 871,153 | New | $60.8M |
| ASO Academy Sports and Outdoors, Inc. | 1.17M | New | $56.4M |
| PBR Petroleo Brasileiro S.A. Petrobras · ADR | 2.66M | New | $55.5M |
| INSP Inspire Medical Systems, Inc. | 639,584 | New | $44.4M |
Added to (104)
| MU Micron Technology, Inc. | 224,405 | +1496% | $224.0M |
| GOOGL Alphabet Inc. Class A | 3.61M | +13.1% | $143.5M |
| VSH Vishay Intertechnology, Inc. | 5.12M | +248% | $118.9M |
| RGEN Repligen Corporation | 1.24M | +57.7% | $87.4M |
| LRCX Lam Research Corporation | 363,995 | +256% | $86.0M |
| STX Seagate Technology Holdings PLC | 276,990 | +45.1% | $79.5M |
| JLL Jones Lang LaSalle Incorporated | 315,152 | +339% | $74.3M |
| RACE Ferrari N.V. | 308,492 | +108% | $63.0M |
| VCYT Veracyte, Inc. | 2.71M | +89.2% | $58.8M |
| TLN Talen Energy Corporation | 677,759 | +36.2% | $56.3M |
Trimmed (245)
| MSFT Microsoft Corporation | 1.71M | -16.5% | -$173.0M |
| AMZN Amazon.com, Inc. | 1.33M | -32.9% | -$163.0M |
| TSM Taiwan Semiconductor Manufacturing Company Ltd. | 4.59M | -7.1% | -$159.4M |
| AZN AstraZeneca PLC | 557,483 | -63.2% | -$155.9M |
| TWST Twist Bioscience Corporation | 1.45M | -33.1% | -$139.2M |
| P Everpure, Inc. | 2.55M | -26.2% | -$118.4M |
| MA Mastercard Incorporated | 707,647 | -22.9% | -$116.0M |
| POWI Power Integrations, Inc. | 208,812 | -91.2% | -$112.6M |
| NVDA NVIDIA Corporation | 8.12M | -5.5% | -$108.6M |
| META Meta Platforms, Inc. | 806,777 | -15.1% | -$103.9M |
Exited (50)
| Teva Pharmaceutical Industries Ltd ADR | 6.59M | Exited | -$223.4M |
| BWIN The Baldwin Insurance Group, Inc. | 6.73M | Exited | -$179.0M |
| SYNA Synaptics Incorporated | 1.24M | Exited | -$154.0M |
| SN SharkNinja, Inc. | 986,806 | Exited | -$150.3M |
| GTX Garrett Motion Inc. | 3.23M | Exited | -$117.1M |
| MLM Martin Marietta Materials, Inc. | 181,902 | Exited | -$104.9M |
| HLIO Helios Technologies, Inc. | 834,221 | Exited | -$74.5M |
| KMT Kennametal Inc. | 1.99M | Exited | -$69.6M |
| CIEN Ciena Corporation | 133,801 | Exited | -$65.6M |
| Marex Group plc | 1.01M | Exited | -$61.5M |
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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Any two quarters side by side. Part of Premium.
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 6, 2026 | 13F-HR | 399 | $30.8B | Current | SEC ↗ |
| Q2 2026 | Aug 12, 2026 | 13F-HR | 403 | $33.3B | Current | SEC ↗ |
| Q1 2026 | May 8, 2026 | 13F-HR | 413 | $30.3B | Current | SEC ↗ |
| Q4 2025 | Feb 9, 2026 | 13F-HR | 413 | $35.9B | Current | SEC ↗ |
| Q3 2025 | Nov 12, 2025 | 13F-HR | 414 | $38.7B | Current | SEC ↗ |
| Q2 2025 | Jul 29, 2025 | 13F-HR | 417 | $37.7B | Current | SEC ↗ |
| Q1 2025 | May 9, 2025 | 13F-HR | 423 | $35.6B | 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