We are live on ! Find out more
William Blair Investment Management

William Blair Investment Management Portfolio holdings

AUM $30.3B
1-Year Est. Return 33.75%
This Fund
S&P 500
This Quarter Est. Return
-0.1%
1 Year Est. Return
+33.75%
3 Year Est. Return
+108.55%
5 Year Est. Return
+126.9%
10 Year Est. Return
+788.31%
AUM
$30.3B
AUM Growth
-$5.59B
Cap. Flow
-$4.09B
Cap. Flow %
-13.52%
Top 10 Hldgs %
30.62%
Holding
459
New
46
Increased
157
Reduced
205
Closed
46

Top Buys

Rank Stock Value
1
AZN icon
AstraZeneca
AZN
+$370M
2
AKAM icon
Akamai
AKAM
+$162M
3
BWA icon
BorgWarner
BWA
+$152M
4
APH icon
Amphenol
APH
+$152M
5
SYNA icon
Synaptics
SYNA
+$129M

Top Sells

Rank Stock Value
1
NVDA icon
NVIDIA
NVDA
+$309M
2
SE icon
Sea Limited
SE
+$302M
3
AMZN icon
Amazon
AMZN
+$269M
4
MSFT icon
Microsoft
MSFT
+$248M
5
CIEN icon
Ciena
CIEN
+$214M

Sector Composition

Rank Sector Weight
1 Technology 36.13%
2 Healthcare 12.59%
3 Industrials 11.81%
4 Financials 11.55%
5 Consumer Discretionary 10.11%
Name Market Value Portfolio Weight Shares or Principal Change
in Stake 		Capital Flow
SKY icon
126
Champion Homes
SKY
$5.14B
$57.7M 0.19%
776,353
-244,347
-24% -$21M
WFRD icon
127
Weatherford International
WFRD
$6.22B
$54.8M 0.18%
579,931
-55,548
-9% -$5.23M
KNX icon
128
Knight Transportation
KNX
$11.4B
$54.3M 0.18%
943,286
+399,047
+73% +$22.9M
MMSI icon
129
Merit Medical Systems
MMSI
$5.32B
$53.6M 0.18%
777,494
-97,365
-11% -$7.61M
BCPC
130
Balchem Corp
BCPC
$5.72B
$53.4M 0.18%
315,260
+16,274
+5% +$2.76M
MOD icon
131
Modine Manufacturing
MOD
$10.4B
$52.7M 0.17%
243,343
-139,572
-36% -$26.3M
TGLS icon
132
Tecnoglass Holdings Inc.
TGLS
$1.96B
$52.3M 0.17%
1,173,073
+243,040
+26% +$11.7M
SPOT icon
133
Spotify
SPOT
$100B
$51.9M 0.17%
106,941
-114,807
-52% -$57.6M
GWRE icon
134
Guidewire Software
GWRE
$14.2B
$51.1M 0.17%
341,501
-16,827
-5% -$2.56M
RSI icon
135
Rush Street Interactive
RSI
$2.88B
$50.7M 0.17%
2,331,047
-226,731
-9% -$4.34M
TEX icon
136
Terex
TEX
$7.74B
$50.4M 0.17%
+853,618
New +$52.9M
CGNX icon
137
Cognex
CGNX
$11.3B
$49.8M 0.16%
1,016,463
-36,817
-3% -$1.72M
WGS icon
138
GeneDx Holdings
WGS
$2.3B
$49.8M 0.16%
775,269
-33,941
-4% -$3.09M
AUB icon
139
Atlantic Union Bankshares
AUB
$5.97B
$49.3M 0.16%
1,380,238
+268,994
+24% +$10.1M
BRBR icon
140
BellRing Brands
BRBR
$1.34B
$48.8M 0.16%
3,032,100
+803,800
+36% +$16.3M
KWR icon
141
Quaker Houghton
KWR
$2.92B
$48.3M 0.16%
388,406
-81,575
-17% -$12.1M
GFI icon
142
Gold Fields
GFI
$36.5B
$46.5M 0.15%
1,024,824
+999,148
+3,891% +$50.2M
OSIS icon
143
OSI Systems
OSIS
$3.89B
$45.6M 0.15%
171,667
-19,659
-10% -$5.44M
TPG icon
144
TPG
TPG
$7.86B
$45.1M 0.15%
1,112,187
-323,562
-23% -$16.6M
AGYS icon
145
Agilysys
AGYS
$3.06B
$44.9M 0.15%
631,587
+58,987
+10% +$5.12M
LTM
146
LATAM Airlines Group S.A.
LTM
$16.3B
$43.6M 0.14%
881,457
+179,099
+25% +$10.1M
LPX icon
147
Louisiana-Pacific
LPX
$5.49B
$43.4M 0.14%
596,108
-233,331
-28% -$19.7M
BE icon
148
Bloom Energy
BE
$64.6B
$43M 0.14%
317,721
-30,471
-9% -$4.47M
TEVA icon
149
Teva Pharmaceuticals
TEVA
$41.2B
$42.9M 0.14%
+1,425,667
New +$45.9M
GPOR icon
150
Gulfport Energy Corp
GPOR
$2.88B
$42.1M 0.14%
198,845
+6,505
+3% +$1.29M
4 5
6
7 8

Similar funds

Barrow, Hanley, Mewhinney & Strauss
Barrow, Hanley, Mewhinney & Strauss Dallas, Texas $30.5B AUM 29.95% 1-Year Est. Return
Lord, Abbett & Co
Lord, Abbett & Co Jersey City, New Jersey $30.6B AUM 57.44% 1-Year Est. Return
Eagle Capital Management (New York)
Eagle Capital Management (New York) New York $29.8B AUM 12.13% 1-Year Est. Return
State of Tennessee, Department of Treasury
State of Tennessee, Department of Treasury Nashville, Tennessee $29.8B AUM 29.48% 1-Year Est. Return
Fuller & Thaler Asset Management
Fuller & Thaler Asset Management San Mateo, California $29.7B AUM 43.33% 1-Year Est. Return
Ohio Public Employees Retirement System (OPERS)
Ohio Public Employees Retirement System (OPERS) Columbus, Ohio $30.9B AUM 29.72% 1-Year Est. Return
Coatue Management
Coatue Management New York $29.1B AUM 96.54% 1-Year Est. Return
Hudson Bay Capital Management
Hudson Bay Capital Management Stamford, Connecticut $29B AUM 30.2% 1-Year Est. Return

William Blair Investment Management's Q1 2026 Portfolio in Review

As of Q1 2026, William Blair Investment Management held 459 positions worth $30.3B, down 16% from $35.9B the previous quarter. Its ten largest holdings account for 31% of the portfolio.

William Blair Investment Management withdrew a net $4.09B in Q1 2026, closing 46 positions and reducing 205 holdings. Its most notable exit was Sea Limited, an estimated $302M position sold in full.

By sector, the portfolio is most concentrated in Technology at 36% of assets, down from 38% a quarter earlier, followed by Healthcare and Industrials.

Against the trend, William Blair Investment Management opened a new position in Akamai worth $186M.

  • William Blair Investment Management's largest Q1 2026 buy was Akamai: 1,619,060 shares worth $186M.
  • William Blair Investment Management added most to AstraZeneca in Q1 2026, an estimated $370M increase.
  • William Blair Investment Management's biggest Q1 2026 reduction was NVIDIA, cutting an estimated $309M.
  • William Blair Investment Management fully exited Sea Limited in Q1 2026, selling an estimated $302M.
  • William Blair Investment Management's ten largest holdings make up 31% of its $30.3B portfolio in Q1 2026.
  • William Blair Investment Management opened 46 new positions and closed 46 in Q1 2026.
  • William Blair Investment Management's portfolio value fell 16% quarter-over-quarter to $30.3B.

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