We are live on ! Find out more
William Blair & Company

William Blair & Company Portfolio holdings

AUM $34.9B
1-Year Est. Return 18.88%
This Fund
S&P 500
This Quarter Est. Return
-3.16%
1 Year Est. Return
+18.88%
3 Year Est. Return
+73.84%
5 Year Est. Return
+90.13%
10 Year Est. Return
+512.03%
AUM
$34.9B
AUM Growth
-$2.36B
Cap. Flow
-$465K
Cap. Flow %
-0%
Top 10 Hldgs %
25.64%
Holding
2,019
New
132
Increased
799
Reduced
746
Closed
97

Top Buys

Rank Stock Value
1
RSP icon
Invesco S&P 500 Equal Weight ETF
RSP
+$224M
2
VEU icon
Vanguard FTSE All-World ex-US ETF
VEU
+$113M
3
PWR icon
Quanta Services
PWR
+$75M
4
GLD icon
SPDR Gold Trust
GLD
+$58.9M
5
BA icon
Boeing
BA
+$55.5M

Top Sells

Rank Stock Value
1
WDAY icon
Workday
WDAY
+$91.2M
2
CWAN
Clearwater Analytics
CWAN
+$78M
3
APP icon
Applovin
APP
+$74.7M
4
TYL icon
Tyler Technologies
TYL
+$69.1M
5
UBER icon
Uber
UBER
+$62.2M

Sector Composition

Rank Sector Weight
1 Technology 21.79%
2 Industrials 14.2%
3 Financials 12.26%
4 Healthcare 10.59%
5 Consumer Discretionary 7.17%
Name Market Value Portfolio Weight Shares or Principal Change
in Stake 		Capital Flow
HSBC icon
1001
HSBC
HSBC
$352B
$812K ﹤0.01%
9,846
-146
-1% -$12.4K
GBIL icon
1002
Goldman Sachs Access Treasury 0-1 Year ETF
GBIL
$7.64B
$812K ﹤0.01%
8,103
+4
+0% +$400
LOB icon
1003
Live Oak Bancshares
LOB
$1.98B
$811K ﹤0.01%
24,523
-5,559
-18% -$205K
SGI
1004
Somnigroup International
SGI
$14.4B
$811K ﹤0.01%
10,969
-3,904
-26% -$339K
AR icon
1005
Antero Resources
AR
$10.9B
$807K ﹤0.01%
+19,020
New +$694K
MOS icon
1006
The Mosaic Company
MOS
$7.19B
$805K ﹤0.01%
31,559
+592
+2% +$16.2K
W icon
1007
Wayfair
W
$11.8B
$803K ﹤0.01%
10,675
+2,442
+30% +$221K
BIL icon
1008
State Street SPDR Bloomberg 1-3 Month T-Bill ETF
BIL
$47.1B
$802K ﹤0.01%
8,752
-4,919
-36% -$450K
NOG icon
1009
Northern Oil and Gas
NOG
$2.29B
$800K ﹤0.01%
+27,380
New +$709K
ETON icon
1010
Eton Pharmaceutcials
ETON
$1.32B
$800K ﹤0.01%
32,400
– –
CTRA
1011
DELISTED
Coterra Energy
CTRA
$799K ﹤0.01%
22,748
-1,158
-5% -$34.8K
WRB icon
1012
W.R. Berkley
WRB
$28.1B
$798K ﹤0.01%
12,043
+872
+8% +$60.1K
OWL icon
1013
Blue Owl Capital
OWL
$6.45B
$798K ﹤0.01%
87,362
+18,479
+27% +$223K
TRU icon
1014
TransUnion
TRU
$16B
$790K ﹤0.01%
11,413
-247,563
-96% -$18.9M
CRL icon
1015
Charles River Laboratories
CRL
$11.3B
$789K ﹤0.01%
+4,575
New +$848K
JHMM icon
1016
John Hancock Multifactor Mid Cap ETF
JHMM
$5.88B
$786K ﹤0.01%
11,714
+598
+5% +$41.1K
DB icon
1017
Deutsche Bank
DB
$66.6B
$786K ﹤0.01%
26,400
-21,396
-45% -$754K
ASTH icon
1018
Astrana Health
ASTH
$1.81B
$781K ﹤0.01%
31,870
-11,031
-26% -$261K
IYM icon
1019
iShares US Basic Materials ETF
IYM
$1.13B
$779K ﹤0.01%
4,426
+3,898
+738% +$682K
ONON icon
1020
On Holding
ONON
$12.6B
$777K ﹤0.01%
22,835
-230,908
-91% -$10.1M
GNR icon
1021
State Street SPDR S&P Global Natural Resources ETF
GNR
$4.75B
$777K ﹤0.01%
10,402
+5,905
+131% +$417K
HYD icon
1022
VanEck High Yield Muni ETF
HYD
$4.44B
$768K ﹤0.01%
15,327
-4,884
-24% -$249K
SUI icon
1023
Sun Communities
SUI
$15.8B
$766K ﹤0.01%
6,084
-163
-3% -$21.1K
CLH icon
1024
Clean Harbors
CLH
$17.2B
$760K ﹤0.01%
2,651
+663
+33% +$181K
IXN icon
1025
iShares Global Tech ETF
IXN
$7.87B
$760K ﹤0.01%
7,598
+419
+6% +$44.3K
39 40
41
42 43

Similar funds

SAM
Storebrand Asset Management Lysaker, Norway $34.8B AUM 25.49% 1-Year Est. Return
Daiwa Securities Group
Daiwa Securities Group Tokyo, Japan $34.8B AUM 20.7% 1-Year Est. Return
Chevy Chase Trust
Chevy Chase Trust Bethesda, Maryland $34.7B AUM 29.45% 1-Year Est. Return
VIA
Vanguard Investments Australia Victoria, Australia $34.6B AUM
Alyeska Investment Group
Alyeska Investment Group Chicago, Illinois $35.4B AUM 33.54% 1-Year Est. Return
Pacer Advisors
Pacer Advisors Malvern, Pennsylvania $35.6B AUM 18.19% 1-Year Est. Return
Kayne Anderson Rudnick Investment Management
Kayne Anderson Rudnick Investment Management Los Angeles, California $34B AUM 6.31% 1-Year Est. Return
Viking Global Investors
Viking Global Investors Stamford, Connecticut $35.7B AUM 21.3% 1-Year Est. Return

William Blair & Company's Q1 2026 Portfolio in Review

As of Q1 2026, William Blair & Company held 2,019 positions worth $34.9B, down 6.3% from $37.3B the previous quarter. Its ten largest holdings account for 26% of the portfolio.

William Blair & Company's Q1 2026 filing shows 132 new, 799 increased, 746 reduced and 97 closed positions. Its largest new stake was Silicon Motion: 103,179 shares worth $11.6M. The largest sale was Workday, an estimated $91.2M.

By sector, the portfolio is most concentrated in Technology at 22% of assets, down from 26% a quarter earlier, followed by Industrials and Financials.

  • William Blair & Company's largest Q1 2026 buy was Silicon Motion: 103,179 shares worth $11.6M.
  • William Blair & Company added most to Invesco S&P 500 Equal Weight ETF in Q1 2026, an estimated $224M increase.
  • William Blair & Company's biggest Q1 2026 reduction was Workday, cutting an estimated $91.2M.
  • William Blair & Company fully exited Dynavax Technologies in Q1 2026, selling an estimated $27.4M.
  • William Blair & Company's ten largest holdings make up 26% of its $34.9B portfolio in Q1 2026.
  • William Blair & Company opened 132 new positions and closed 97 in Q1 2026.
  • William Blair & Company's portfolio value fell 6.3% quarter-over-quarter to $34.9B.

Based on William Blair & Company's 13F filing for Q1 2026, filed 8 May 2026.