William Blair & Company Portfolio holdings
William Blair & Company is an independent investment bank owned by its own employees. It opened in 1935 under its founder, William McCormick Blair. Besides investment banking, it does equity research, trading, investment management and private wealth management. Its bankers advise corporations, financial sponsors and owner-entrepreneurs on deals such as mergers and acquisitions. Its private wealth business looks after high net worth individuals and families, and also serves business owners, foundations and endowments.
Top Buys
| Rank | Stock | Value |
|---|---|---|
| 1 |
HONA
Honeywell Aerospace
HONA
|
+$100M |
| 2 |
Arista Networks
ANET
|
+$71.2M |
| 3 |
Invesco S&P 500 Equal Weight ETF
RSP
|
+$61.8M |
| 4 |
Vanguard Morningstar Total Stock Market ETF
VTI
|
+$55.8M |
| 5 |
Miami International Holdings
MIAX
|
+$49.4M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
ExxonMobil
XOM
|
+$161M |
| 2 |
Copart
CPRT
|
+$62M |
| 3 |
Danaher
DHR
|
+$59.1M |
| 4 |
Apple
AAPL
|
+$57M |
| 5 |
Veeva Systems
VEEV
|
+$52.2M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 24.38% |
| 2 | Miscellaneous | 18.67% |
| 3 | Industrials | 15.33% |
| 4 | Financials | 11.07% |
| 5 | Healthcare | 9.11% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | Held Since | |
|---|---|---|---|---|---|---|---|
|
1
Apple
AAPL
$5.1T
| $1.66B | 4.32% |
5,731,525
-199,389
| -3% | -$57M |
2013 Q2
52 quarters
|
|
2
Amazon
AMZN
$2.89T
| $1.4B | 3.65% |
5,875,124
-182,814
| -3% | -$45.9M |
2013 Q2
52 quarters
|
|
3
Microsoft
MSFT
$4.05T
| $1.28B | 3.35% |
3,442,574
-55,536
| -2% | -$22.5M |
2013 Q2
52 quarters
|
|
4
NVIDIA
NVDA
$4.31T
| $1.08B | 2.8% |
5,374,424
-53,451
| -1% | -$11M |
2016 Q1
41 quarters
|
|
5
Alphabet (Google) Class C
GOOG
$3.52T
| $1.04B | 2.72% |
2,953,724
-82,041
| -3% | -$29.3M |
2013 Q2
52 quarters
|
|
6
Alphabet (Google) Class A
GOOGL
$3.54T
| $859M | 2.24% |
2,402,621
-33,496
| -1% | -$12.1M |
2015 Q4
42 quarters
|
|
7
GE Vernova
GEV
$220B
| $775M | 2.02% |
659,673
-4,930
| -0.7% | -$5.03M |
2024 Q2
8 quarters
|
|
8
JPMorgan Chase
JPM
$908B
| $743M | 1.94% |
2,270,360
-36,893
| -2% | -$11.5M |
2013 Q2
52 quarters
|
|
9
State Street SPDR S&P 500 ETF Trust
SPY
$799B
| $633M | 1.65% |
848,034
+2,740
| +0.3% | +$1.99M |
2013 Q2
52 quarters
|
|
10
Visa
V
$788B
| $632M | 1.65% |
1,841,604
-2,979
| -0.2% | -$956K |
2013 Q2
52 quarters
|
|
11
Costco
COST
$472B
| $491M | 1.28% |
524,692
+3,415
| +0.7% | +$3.4M |
2013 Q2
52 quarters
|
|
12
Idexx Laboratories
IDXX
$55.7B
| $484M | 1.26% |
918,556
-27,780
| -3% | -$15.6M |
2013 Q2
52 quarters
|
|
13
Amphenol
APH
$199B
| $442M | 1.15% |
5,008,818
-31,820
| -0.6% | -$2.29M |
2013 Q2
52 quarters
|
|
14
Mastercard
MA
$571B
| $433M | 1.13% |
842,350
-81,055
| -9% | -$40.4M |
2013 Q2
52 quarters
|
|
|
15
Invesco S&P 500 Equal Weight ETF
RSP
$103B
| $422M | 1.1% |
1,982,392
+301,788
| +18% | +$61.8M |
2018 Q2
32 quarters
|
|
16
Palo Alto Networks
PANW
$271B
| $418M | 1.09% |
1,226,519
-78,339
| -6% | -$17.9M |
2013 Q2
52 quarters
|
|
17
Eli Lilly
LLY
$1.26T
| $416M | 1.08% |
347,098
+23,080
| +7% | +$23.6M |
2013 Q2
52 quarters
|
|
18
Meta Platforms (Facebook)
META
$1.64T
| $378M | 0.98% |
670,881
-50,839
| -7% | -$31.1M |
2013 Q2
52 quarters
|
|
19
Vanguard FTSE All-World ex-US ETF
VEU
$67.1B
| $375M | 0.98% |
4,479,218
+310,593
| +7% | +$25.4M |
2013 Q2
52 quarters
|
|
20
Micron Technology
MU
$830B
| $365M | 0.95% |
315,878
-16,433
| -5% | -$12.3M |
2013 Q2
52 quarters
|
|
21
iShares Core S&P 500 ETF
IVV
$873B
| $363M | 0.95% |
484,704
-1,135
| -0.2% | -$827K |
2013 Q2
52 quarters
|
|
22
Fastenal
FAST
$62.6B
| $356M | 0.93% |
7,407,059
+33,352
| +0.5% | +$1.51M |
2013 Q2
52 quarters
|
|
23
Broadcom
AVGO
$1.53T
| $351M | 0.91% |
929,716
+11,388
| +1% | +$4.57M |
2018 Q4
30 quarters
|
|
24
AbbVie
ABBV
$518B
| $324M | 0.84% |
1,287,857
-46,252
| -3% | -$10M |
2013 Q2
52 quarters
|
|
25
Vanguard FTSE Developed Markets ETF
VEA
$231B
| $306M | 0.8% |
4,291,023
+428,937
| +11% | +$29.9M |
2013 Q2
52 quarters
|
|
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William Blair & Company's Q2 2026 Portfolio in Review
As of Q2 2026, William Blair & Company held 2,083 positions worth $38.4B, up 10% from $34.9B the previous quarter. Its ten largest holdings account for 26% of the portfolio.
William Blair & Company's Q2 2026 filing shows 163 new, 891 increased, 708 reduced and 85 closed positions. Its largest new stake was Honeywell Aerospace: 454,071 shares worth $100M. The largest sale was ExxonMobil, an estimated $161M.
By sector, the portfolio is most concentrated in Technology at 24% of assets, up from 22% a quarter earlier, followed by Miscellaneous and Industrials.
- William Blair & Company's largest Q2 2026 buy was Honeywell Aerospace: 454,071 shares worth $100M.
- William Blair & Company added most to Arista Networks in Q2 2026, an estimated $71.2M increase.
- William Blair & Company's biggest Q2 2026 reduction was Copart, cutting an estimated $62M.
- William Blair & Company fully exited ExxonMobil in Q2 2026, selling an estimated $161M.
- William Blair & Company's ten largest holdings make up 26% of its $38.4B portfolio in Q2 2026.
- William Blair & Company opened 163 new positions and closed 85 in Q2 2026.
- William Blair & Company's portfolio value rose 10% quarter-over-quarter to $38.4B.
Based on William Blair & Company's 13F filing for Q2 2026, filed 11 Aug 2026.