WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC — 13F Holdings & Portfolio
CIK 1644956 · latest 13F-HR filed 2026-05-08
WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC manages $30.26B in 13F-reported U.S. long-equity assets across 413 reported positions as of its 2026-03-31 13F-HR filing. Its largest disclosed positions are TSM (6.16%), NVDA (5.15%), AAPL (4.04%). Quarter over quarter (versus its 2025-12-31 filing) the fund opened 47 new positions, exited 47, added to 114, and trimmed 209.
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.
$30.26B
Long-equity book
413
Distinct positions
2026-03-31
Filed 2026-05-08
+47 / −47 / ↑114 / ↓209
vs 2025-12-31
| Name | Title / Status | Ownership | Type |
|---|
Top Adds (vs prior quarter)
- STERLING INFRASTRUCTURE INC$119.1M +942.6%
- C H ROBINSON WORLDWIDE IN$102.7M +146.0%
- MILLICOM INTL CELLULAR S A$98.4M +1417.9%
- GRAND CANYON ED INC$91.2M +121.0%
- NEXTPOWER INC$76.9M +64.8%
Top Trims
- MICROSOFT CORP-$615.7M -36.5%
- NVIDIA CORPORATION-$422.8M -21.3%
- AMAZON COM INC-$353.7M -34.9%
- ALPHABET INC-$267.3M -27.1%
- APPLE INC-$258.7M -17.5%
New Positions
- ASTRAZENECA PLC$377.3M
- AKAMAI TECHNOLOGIES INC$185.9M
- BORGWARNER INC$156.5M
- AMPHENOL CORP$136.1M
- POWER INTEGRATIONS INC$121.9M
Exited Positions
- SEA LTD$302.4M
- WAYSTAR HLDG CORP$173.0M
- AMICUS THERAPEUTICS INC$151.3M
- WESTERN ALLIANCE BANCORP$143.9M
- CLEARWATER ANALYTICS HLDGS I$141.8M
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 | TAIWAN SEMICONDUCTOR MANUFAC | TSM | 874039100 | $1.87B | 6.16% | 5,518,260 | SH |
| 2 | NVIDIA CORPORATION | NVDA | 67066G104 | $1.56B | 5.15% | 8,941,756 | SH |
| 3 | APPLE INC | AAPL | 037833100 | $1.22B | 4.04% | 4,812,433 | SH |
| 4 | MICROSOFT CORP | MSFT | 594918104 | $1.07B | 3.54% | 2,896,782 | SH |
| 5 | ALPHABET INC | GOOGL | 02079K305 | $720.2M | 2.38% | 2,504,605 | SH |
| 6 | BROADCOM INC | AVGO | 11135F101 | $681.4M | 2.25% | 2,201,558 | SH |
| 7 | AMAZON COM INC | AMZN | 023135106 | $658.9M | 2.18% | 3,163,629 | SH |
| 8 | META PLATFORMS INC | META | 30303M102 | $579.6M | 1.92% | 1,013,122 | SH |
| 9 | MASTERCARD INCORPORATED | MA | 57636Q104 | $530.0M | 1.75% | 1,060,651 | SH |
| 10 | ASTRAZENECA PLC | AZN | G0593M107 | $377.3M | 1.25% | 1,942,155 | SH |
| 11 | LINDE PLC | LIN | G54950103 | $315.5M | 1.04% | 636,338 | SH |
| 12 | CARLYLE GROUP INC | CG | 14316J108 | $304.9M | 1.01% | 6,301,109 | SH |
| 13 | COSTCO WHOLESALE CORPORATION | COST | 22160K105 | $301.4M | 1.00% | 302,468 | SH |
| 14 | ITAU UNIBANCO HLDG S A | ITUB | 465562106 | $265.6M | 0.88% | 31,684,708 | SH |
| 15 | TWIST BIOSCIENCE CORP | TWST | 90184D100 | $250.4M | 0.83% | 5,269,718 | SH |
| 16 | SERVICENOW INC | NOW | 81762P102 | $248.0M | 0.82% | 2,371,614 | SH |
| 17 | PRIMO BRANDS CORPORATION | PRMB | 741623102 | $245.8M | 0.81% | 13,056,192 | SH |
| 18 | MUELLER INDS INC | MLI | 624756102 | $233.8M | 0.77% | 2,109,729 | SH |
| 19 | INTUIT | INTU | 461202103 | $230.8M | 0.76% | 533,736 | SH |
| 20 | MONSTER BEVERAGE CORP NEW | MNST | 61174X109 | $212.7M | 0.70% | 2,935,247 | SH |
| 21 | ADVANCED MICRO DEVICES INC | AMD | 007903107 | $212.1M | 0.70% | 1,042,594 | SH |
| 22 | CREDICORP LTD | BAP | G2519Y108 | $211.2M | 0.70% | 622,690 | SH |
| 23 | AGILENT TECHNOLOGIES INC | A | 00846U101 | $204.7M | 0.68% | 1,795,764 | SH |
| 24 | OREILLY AUTOMOTIVE INC | ORLY | 67103H107 | $204.0M | 0.67% | 2,210,034 | SH |
| 25 | BWX TECHNOLOGIES INC | BWXT | 05605H100 | $200.8M | 0.66% | 981,782 | SH |
| 26 | TRANSUNION | TRU | 89400J107 | $200.0M | 0.66% | 2,891,187 | SH |
| 27 | ONTO INNOVATION INC | ONTO | 683344105 | $197.7M | 0.65% | 964,213 | SH |
| 28 | IDEXX LABS INC | IDXX | 45168D104 | $197.6M | 0.65% | 351,621 | SH |
| 29 | NEXTPOWER INC | NXT | 65290E101 | $195.6M | 0.65% | 1,622,489 | SH |
| 30 | ARGENX SE | ARGX | 04016X101 | $194.4M | 0.64% | 266,067 | SH |
| 31 | CAVA GROUP INC | CAVA | 148929102 | $193.7M | 0.64% | 2,393,971 | SH |
| 32 | LATTICE SEMICONDUCTOR CORP | LSCC | 518415104 | $189.6M | 0.63% | 2,043,720 | SH |
| 33 | F5 INC | FFIV | 315616102 | $188.0M | 0.62% | 649,948 | SH |
| 34 | AKAMAI TECHNOLOGIES INC | AKAM | 00971T101 | $185.9M | 0.61% | 1,619,060 | SH |
| 35 | CAMECO CORP | CCJ | 13321L108 | $182.7M | 0.60% | 1,682,303 | SH |
| 36 | UNITEDHEALTH GROUP INC | UNH | 91324P102 | $182.2M | 0.60% | 673,263 | SH |
| 37 | MADRIGAL PHARMACEUTICALS INC | MDGL | 558868105 | $178.3M | 0.59% | 340,519 | SH |
| 38 | NU HLDGS LTD | NU | G6683N103 | $176.3M | 0.58% | 12,267,600 | SH |
| 39 | GLOBUS MED INC | GMED | 379577208 | $173.2M | 0.57% | 2,009,763 | SH |
| 40 | C H ROBINSON WORLDWIDE IN | CHRW | 12541W209 | $173.0M | 0.57% | 1,041,658 | SH |
| 41 | EVERPURE INC | P | 74624M102 | $170.1M | 0.56% | 2,881,481 | SH |
| 42 | SNOWFLAKE INC | SNOW | 833445109 | $170.1M | 0.56% | 1,127,525 | SH |
| 43 | TALEN ENERGY CORP | TLN | 87422Q109 | $167.7M | 0.55% | 525,214 | SH |
| 44 | GRAND CANYON ED INC | LOPE | 38526M106 | $166.6M | 0.55% | 979,734 | SH |
| 45 | EVEREST GROUP LTD | EG | G3223R108 | $165.4M | 0.55% | 506,166 | SH |
| 46 | HALOZYME THERAPEUTICS INC | HALO | 40637H109 | $163.3M | 0.54% | 2,525,975 | SH |
| 47 | MARTIN MARIETTA MATLS INC | MLM | 573284106 | $160.4M | 0.53% | 272,392 | SH |
| 48 | COHERENT CORP | COHR | 19247G107 | $159.2M | 0.53% | 668,137 | SH |
| 49 | CURTISS WRIGHT CORP | CW | 231561101 | $158.1M | 0.52% | 232,069 | SH |
| 50 | REGAL REXNORD CORPORATION | RRX | 758750103 | $156.8M | 0.52% | 837,493 | SH |
| Period | Filed | AUM | Holdings | Accession |
|---|---|---|---|---|
| 2026-03-31 | 2026-05-08 | $30.26B | 413 | 0001644956-26-000021 |
| 2025-12-31 | 2026-02-09 | $35.85B | 413 | 0001644956-26-000007 |