William Blair Investment Management, LLC 13F holdings
William Blair Investment Management, LLC reported 397 positions with a total reported value of $33.3B as of 2026-06-30, in its 13F for Q2 2026, filed 2026-08-12. Top holdings by reported value: TSM TAIWAN SEMICONDUCTOR MANUFAC (7.1%), NVDA NVIDIA CORPORATION (5.2%), GOOGL ALPHABET INC (3.4%), AAPL APPLE INC (2.8%), AVGO BROADCOM INC (2.3%). Against 2026-03-31 it opened 46 new positions and exited 56. Next 13F due by 2026-11-14, the legal deadline 45 days after the quarter ending 2026-09-30.
Email me when William Blair Investment Management, LLC files its 13F
A free account follows up to 10 funds. New 13F filings arrive in your daily or weekly digest. No password and no card.
Top holdings
25 largest of 397 positions · reported value as of 2026-06-30
| Holding | Shares | Reported value | % of portfolio |
|---|---|---|---|
| TSM TAIWAN SEMICONDUCTOR MANUFAC | 4,936,408 | $2.4B | 7.1% |
| NVDA NVIDIA CORPORATION | 8,599,021 | $1.7B | 5.2% |
| GOOGL ALPHABET INC | 3,193,797 | $1.1B | 3.4% |
| AAPL APPLE INC | 3,259,914 | $943.3M | 2.8% |
| AVGO BROADCOM INC | 2,056,135 | $776.7M | 2.3% |
| MSFT MICROSOFT CORP | 2,048,642 | $764.2M | 2.3% |
| META META PLATFORMS INC | 950,115 | $535.2M | 1.6% |
| AMZN AMAZON COM INC | 1,987,085 | $473.6M | 1.4% |
| MA MASTERCARD INCORPORATED | 918,005 | $471.5M | 1.4% |
| AMD ADVANCED MICRO DEVICES INC | 763,517 | $443.5M | 1.3% |
| APPLIED MATLS INC | 497,946 | $360.0M | 1.1% |
| GE AEROSPACE | 790,801 | $295.5M | 0.9% |
| AZN ASTRAZENECA PLC | 1,514,795 | $283.2M | 0.9% |
| PRMB PRIMO BRANDS CORPORATION | 11,426,823 | $279.3M | 0.8% |
| P EVERPURE INC | 3,455,381 | $272.2M | 0.8% |
| APH AMPHENOL CORP | 1,535,059 | $270.7M | 0.8% |
| LIN LINDE PLC | 504,953 | $262.0M | 0.8% |
| ONTO ONTO INNOVATION INC | 665,377 | $251.8M | 0.8% |
| BWA BORGWARNER INC | 3,784,707 | $251.3M | 0.8% |
| CG CARLYLE GROUP INC | 5,914,905 | $249.1M | 0.7% |
| ARGX ARGENX SE | 264,617 | $245.5M | 0.7% |
| MUELLER INDS INC | 1,986,139 | $244.2M | 0.7% |
| MNST MONSTER BEVERAGE CORP NEW | 2,538,136 | $244.0M | 0.7% |
| FFIV F5 INC | 586,271 | $243.9M | 0.7% |
| BAP CREDICORP LTD | 625,144 | $243.5M | 0.7% |
SEC FORM 13F · Q2 2026 · VALUES AS REPORTED, NOT PRICES
New positions this quarter
Held at 2026-06-30, not at 2026-03-31 · 46 in all · reported value as of 2026-06-30
| Holding | Shares | Reported value | % of portfolio |
|---|---|---|---|
| GE AEROSPACE | 790,801 | $295.5M | 0.9% |
| CRWD CROWDSTRIKE HLDGS INC | 281,409 | $214.8M | 0.6% |
| STX SEAGATE TECHNOLOGY HLDNGS PL | 190,847 | $184.2M | 0.6% |
| CANADIAN NAT RES LTD MED TER | 3,635,082 | $143.7M | 0.4% |
| FPS FORGENT POWER SOLUTIONS INC | 2,516,270 | $140.6M | 0.4% |
| PTCT PTC THERAPEUTICS INC | 1,722,688 | $140.5M | 0.4% |
| ETSY ETSY INC | 1,598,520 | $120.4M | 0.4% |
| RGEN REPLIGEN CORP | 788,571 | $107.6M | 0.3% |
| HBM HUDBAY MINERALS INC | 4,215,842 | $99.5M | 0.3% |
| AAOI APPLIED OPTOELECTRONICS INC | 504,202 | $74.7M | 0.2% |
| LRN STRIDE INC | 823,698 | $71.0M | 0.2% |
| SPCX SPACE EXPLORATION TECHN CORP | 349,477 | $59.7M | 0.2% |
| CRCL CIRCLE INTERNET GROUP INC | 861,252 | $53.9M | 0.2% |
| AMX AMERICA MOVIL SAB DE CV | 2,010,385 | $52.2M | 0.2% |
| KRMN KARMAN HLDGS INC | 977,462 | $48.8M | 0.1% |
| PRIMORIS SVCS CORP | 399,966 | $39.6M | 0.1% |
| DPC DPC HOLDINGS PLC | 640,005 | $31.4M | <0.1% |
| CIB GRUPO CIBEST SA | 356,370 | $28.3M | <0.1% |
| WBI WATERBRIDGE INFRASTRUCTURE L | 783,780 | $26.9M | <0.1% |
| RMBS RAMBUS INC DEL | 200,116 | $26.6M | <0.1% |
| SARO STANDARDAERO INC | 884,307 | $26.4M | <0.1% |
| HAE HAEMONETICS CORP MASS | 332,075 | $24.9M | <0.1% |
| EEFT EURONET WORLDWIDE INC | 315,386 | $23.1M | <0.1% |
| CTRE CARETRUST REIT INC | 570,637 | $23.0M | <0.1% |
| CHEFS WHSE INC | 194,636 | $18.7M | <0.1% |
Sold out
Held at 2026-03-31, gone by 2026-06-30 · 56 in all · reported value as of 2026-03-31
| Holding | Shares 2026-03-31 | Reported value | % of portfolio then |
|---|---|---|---|
| COHR COHERENT CORP | 668,137 | $159.2M | 0.5% |
| VEEV VEEVA SYS INC | 643,325 | $113.0M | 0.4% |
| DOCS DOXIMITY INC | 4,834,220 | $112.6M | 0.4% |
| PLNT PLANET FITNESS MASTER ISSUER | 1,452,642 | $108.0M | 0.4% |
| POOL POOL CORP | 452,273 | $91.5M | 0.3% |
| ADVANCED DRAIN SYS INC DEL | 655,684 | $89.9M | 0.3% |
| PSN PARSONS CORP DEL | 1,487,529 | $80.6M | 0.3% |
| TYL TYLER TECHNOLOGIES INC | 215,748 | $73.9M | 0.2% |
| INSPIRE MED SYS INC | 1,137,384 | $58.7M | 0.2% |
| SPOT SPOTIFY TECHNOLOGY S A | 106,941 | $51.9M | 0.2% |
| BRBR BELLRING BRANDS INC | 3,032,100 | $48.8M | 0.2% |
| GFI GOLD FIELDS LTD | 1,024,824 | $46.5M | 0.2% |
| LPX LOUISIANA PAC CORP | 596,108 | $43.4M | 0.1% |
| BE BLOOM ENERGY CORP | 317,721 | $43.0M | 0.1% |
| SILA REALTY TRUST INC | 1,387,324 | $32.9M | 0.1% |
| THERMON GROUP HLDGS INC | 647,539 | $32.6M | 0.1% |
| ACVA ACV AUCTIONS INC | 7,212,623 | $30.6M | 0.1% |
| PODD INSULET CORP | 139,130 | $29.2M | <0.1% |
| SMPL SIMPLY GOOD FOODS CO | 1,910,640 | $27.4M | <0.1% |
| TRI POINTE HOMES INC | 574,030 | $26.8M | <0.1% |
| IIIV I3 VERTICALS INC | 1,176,960 | $26.3M | <0.1% |
| WSC WILLSCOT HLDGS CORP | 1,494,201 | $25.9M | <0.1% |
| AMPX AMPRIUS TECHNOLOGIES INC | 1,170,131 | $19.7M | <0.1% |
| AEHR AEHR TEST SYS | 513,293 | $19.0M | <0.1% |
| LITE LUMENTUM HLDGS INC | 26,579 | $18.7M | <0.1% |
Biggest increases and decreases
Positions held at both quarter ends, by change in shares · reported value as of 2026-06-30
Increases
| Holding | Shares 2026-03-31 | Shares 2026-06-30 | Change | Reported value |
|---|---|---|---|---|
| APPLIED MATLS INC | 34,940 | 497,946 | +1,325.1% | $360.0M |
| GOOGL ALPHABET INC | 2,505,630 | 3,193,797 | +27.5% | $1.1B |
| TEVA TEVA PHARMACEUTICAL INDS LTD | 1,425,667 | 6,593,221 | +362.5% | $223.4M |
| TKR TIMKEN CO | 5,176 | 954,839 | +18,347.4% | $138.8M |
| DIOD DIODES INC | 441,562 | 1,682,686 | +281.1% | $184.2M |
| WST WEST PHARMACEUTICAL SVSC INC | 39,725 | 417,309 | +950.5% | $149.8M |
| MIRM MIRUM PHARMACEUTICALS INC | 335,669 | 1,404,741 | +318.5% | $164.5M |
| JAZZ JAZZ PHARMACEUTICALS PLC | 70,883 | 436,893 | +516.4% | $105.3M |
| APH AMPHENOL CORP | 1,077,434 | 1,535,059 | +42.5% | $270.7M |
| MARRIOTT INTL INC NEW | 84,631 | 300,872 | +255.5% | $111.5M |
| BSY BENTLEY SYS INC | 3,322,723 | 5,942,507 | +78.8% | $177.6M |
| TTE TOTALENERGIES SE | 853,751 | 1,819,275 | +113.1% | $141.4M |
Decreases
| Holding | Shares 2026-03-31 | Shares 2026-06-30 | Change | Reported value |
|---|---|---|---|---|
| AAPL APPLE INC | 4,812,433 | 3,259,914 | -32.3% | $943.3M |
| TWST TWIST BIOSCIENCE CORP | 5,269,718 | 2,174,594 | -58.7% | $223.7M |
| MSFT MICROSOFT CORP | 2,896,782 | 2,048,642 | -29.3% | $764.2M |
| AMZN AMAZON COM INC | 3,163,629 | 1,987,085 | -37.2% | $473.6M |
| TSM TAIWAN SEMICONDUCTOR MANUFAC | 5,518,260 | 4,936,408 | -10.5% | $2.4B |
| TECH BIO-TECHNE CORP | 2,462,487 | 4,060 | -99.8% | $286.8K |
| AMD ADVANCED MICRO DEVICES INC | 1,042,594 | 763,517 | -26.8% | $443.5M |
| DCI DONALDSON INC | 1,615,349 | 34,964 | -97.8% | $3.1M |
| LSCC LATTICE SEMICONDUCTOR CORP | 2,043,720 | 1,160,417 | -43.2% | $177.5M |
| CIEN CIENA CORP | 398,579 | 133,801 | -66.4% | $65.6M |
| MELI MERCADOLIBRE INC | 74,849 | 441 | -99.4% | $748.5K |
| NXT NEXTPOWER INC | 1,622,489 | 671,767 | -58.6% | $80.0M |
CIK 1644956 · 13F FILINGS ON EDGAR · INFORMATIONAL ONLY
More 13F data
Source: U.S. Securities and Exchange Commission (EDGAR) and other official
government data · Updated 2026-10-12 ·
For informational purposes only, not investment advice.
Privacy · Terms