Institutional Manager · CIK 0001644956
WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC
CHICAGO, IL · File #028-17022
Latest AUM
$35.85B
Positions
413
Top-10 Concentration
54.5%
Filings
9
Portfolio Value Over Time
2024-03
2024-06
2024-09
2024-12
2025-03
2025-06
2025-09
2025-12
Biggest QoQ Changes
Ranked by conviction flow (share change × current price) so mark-to-market moves don't dominate. Price effect column shows how much of the $ change was just the stock moving.
| Action | Issuer | Ticker / CUSIP | Δ Shares | Flow ($) | Price Effect |
|---|---|---|---|---|---|
| REDUCE | CIENA CORP | CIEN | -1,342,295 | -$313.9M | +$215.3M |
| REDUCE | LAM RESEARCH CORP | LRCX | -1,732,948 | -$296.6M | +$68.7M |
| ADD | SERVICENOW INC | NOW | +1,774,770 | +$271.9M | -$286.9M |
| REDUCE | ROYAL BK CDA | 780087102 | -1,421,835 | -$242.4M | +$33.2M |
| EXITED | LIVE NATION ENTERTAINMENT IN | 538034109 | -1,400,174 | -$228.8M | $0 |
| EXITED | STRIDE INC | 86333M108 | -1,511,080 | -$225.1M | $0 |
| REDUCE | UBER TECHNOLOGIES INC | UBER | -2,590,339 | -$211.7M | -$43.0M |
| ADD | ALPHABET INC | GOOG | +668,971 | +$209.4M | +$173.8M |
| NEW | ARGENX SE | ARGX | +223,666 | +$188.1M | $0 |
| ADD | SNOWFLAKE INC | SNOW | +828,789 | +$181.8M | -$3.2M |
Sector Allocation
Filing History
- 13F HOLDINGS REPORTQ/E Dec 2025413 pos · $35.85B
- 13F HOLDINGS REPORTQ/E Sep 2025414 pos · $38.67B
- 13F HOLDINGS REPORTQ/E Jun 2025417 pos · $37.68B
- 13F HOLDINGS REPORTQ/E Mar 2025423 pos · $35.62B
- 13F HOLDINGS REPORTQ/E Dec 2024433 pos · $40.94B
- 13F HOLDINGS REPORTQ/E Sep 2024412 pos · $40.53B
- 13F HOLDINGS REPORTQ/E Jun 2024411 pos · $38.12B
- 13F HOLDINGS REPORTQ/E Mar 2024410 pos · $38.69B
- 13F HOLDINGS REPORTQ/E Dec 2023398 pos · $30.09B
Top 20 Holdings — Dec 2025
| # | Issuer | Ticker | Shares | Value | % of Portfolio |
|---|---|---|---|---|---|
| 1 | NVIDIA CORPORATION | NVDA | 10,628,667 | $1.98B | 9.26% |
| 2 | TAIWAN SEMICONDUCTOR MFG LTD | 874039100 | 5,985,330 | $1.82B | 8.50% |
| 3 | MICROSOFT CORP | MSFT | 3,490,302 | $1.69B | 7.89% |
| 4 | APPLE INC | AAPL | 5,444,328 | $1.48B | 6.92% |
| 5 | AMAZON COM INC | AMZN | 4,387,003 | $1.01B | 4.73% |
| 6 | ALPHABET INC | GOOG | 3,154,973 | $987.5M | 4.61% |
| 7 | BROADCOM INC | AVGO | 2,536,611 | $877.9M | 4.10% |
| 8 | META PLATFORMS INC | META | 1,186,769 | $783.4M | 3.66% |
| 9 | MASTERCARD INCORPORATED | MA | 1,084,947 | $619.4M | 2.89% |
| 10 | CARLYLE GROUP INC | CGABL | 7,131,902 | $421.6M | 1.97% |
| 11 | TRANSUNION | TRU | 3,965,495 | $340.0M | 1.59% |
| 12 | MERCADOLIBRE INC | MELI | 165,579 | $333.5M | 1.56% |
| 13 | SERVICENOW INC | NOW | 2,148,780 | $329.2M | 1.54% |
| 14 | NU HLDGS LTD | NU | 18,699,367 | $313.0M | 1.46% |
| 15 | SEA LTD | SE | 2,370,876 | $302.4M | 1.41% |
| 16 | IDEXX LABS INC | 45168D104 | 441,324 | $298.6M | 1.39% |
| 17 | SNOWFLAKE INC | SNOW | 1,346,998 | $295.5M | 1.38% |
| 18 | INTUIT | INTU | 442,391 | $293.0M | 1.37% |
| 19 | MONSTER BEVERAGE CORP NEW | MNST | 3,761,249 | $288.4M | 1.35% |
| 20 | ADVANCED MICRO DEVICES INC | AMD | 1,339,546 | $286.9M | 1.34% |