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
+1.73%
1 Year Est. Return
+18.88%
3 Year Est. Return
+73.84%
5 Year Est. Return
+90.13%
10 Year Est. Return
+563.35%
AUM
$37.3B
AUM Growth
-$310M
Cap. Flow
-$212M
Cap. Flow %
-0.57%
Top 10 Hldgs %
27.41%
Holding
1,963
New
120
Increased
759
Reduced
753
Closed
96

Top Buys

Rank Stock Value
1
BWXT icon
BWX Technologies
BWXT
+$46.6M
2
META icon
Meta Platforms (Facebook)
META
+$38.3M
3
NOW icon
ServiceNow
NOW
+$37.6M
4
VEU icon
Vanguard FTSE All-World ex-US ETF
VEU
+$32.4M
5
GLD icon
SPDR Gold Trust
GLD
+$29.4M

Top Sells

Rank Stock Value
1
FISV
Fiserv Inc
FISV
+$114M
2
CSGP icon
CoStar Group
CSGP
+$78.3M
3
CWAN
Clearwater Analytics
CWAN
+$75.3M
4
POOL icon
Pool Corp
POOL
+$54M
5
ZTS icon
Zoetis
ZTS
+$51.3M

Sector Composition

Rank Sector Weight
1 Technology 25.8%
2 Financials 13.4%
3 Industrials 12.04%
4 Healthcare 11.22%
5 Communication Services 7.63%
Name Market Value Portfolio Weight Shares or Principal Change
in Stake 		Capital Flow
ARGX icon
226
argenx
ARGX
$54.1B
$22.2M 0.06%
26,340
+23,957
+1,005% +$20.5M
WING icon
227
Wingstop
WING
$3.18B
$21.6M 0.06%
+90,773
New +$22.5M
C icon
228
Citigroup
C
$226B
$21.5M 0.06%
184,662
+16,013
+9% +$1.66M
ZBRA icon
229
Zebra Technologies
ZBRA
$17.8B
$21.1M 0.06%
86,891
+341
+0.4% +$91.2K
XLV icon
230
State Street Health Care Select Sector SPDR ETF
XLV
$43.3B
$20.7M 0.06%
133,987
+19,865
+17% +$2.98M
AMAT icon
231
Applied Materials
AMAT
$428B
$20.4M 0.05%
79,410
-4,855
-6% -$1.16M
ESGD icon
232
iShares ESG Aware MSCI EAFE ETF
ESGD
$12.3B
$20.3M 0.05%
213,412
+2,344
+1% +$221K
HOOD icon
233
Robinhood
HOOD
$83.9B
$20M 0.05%
176,989
+2,051
+1% +$267K
ARES icon
234
Ares Management
ARES
$30.9B
$19.9M 0.05%
122,935
+26,412
+27% +$4.11M
VMC icon
235
Vulcan Materials
VMC
$36.9B
$19.9M 0.05%
69,601
-4,594
-6% -$1.35M
AVAV icon
236
AeroVironment
AVAV
$9.45B
$19.8M 0.05%
82,012
-5,127
-6% -$1.61M
IRM icon
237
Iron Mountain
IRM
$36.1B
$19.8M 0.05%
238,285
-80,125
-25% -$7.5M
AZN icon
238
AstraZeneca
AZN
$250B
$19.4M 0.05%
105,592
+540
+0.5% +$94.7K
ROP icon
239
Roper Technologies
ROP
$39.8B
$19.4M 0.05%
43,578
+6,300
+17% +$2.92M
BMY icon
240
Bristol-Myers Squibb
BMY
$132B
$19.4M 0.05%
358,924
-46,716
-12% -$2.25M
MDLZ icon
241
Mondelez International
MDLZ
$79.9B
$19.2M 0.05%
356,608
+78,252
+28% +$4.51M
DSGX icon
242
Descartes Systems
DSGX
$6.82B
$19.1M 0.05%
217,667
-127,934
-37% -$11.4M
BABA icon
243
Alibaba
BABA
$308B
$19.1M 0.05%
130,030
+41,575
+47% +$6.77M
RCL icon
244
Royal Caribbean
RCL
$85.6B
$19M 0.05%
68,088
+15,234
+29% +$4.3M
SPHQ icon
245
Invesco S&P 500 Quality ETF
SPHQ
$19.7B
$18.8M 0.05%
250,837
+9,842
+4% +$731K
NTRS icon
246
Northern Trust
NTRS
$33.9B
$18.8M 0.05%
137,715
-841
-0.6% -$110K
PAUG icon
247
Innovator US Equity Power Buffer ETF August
PAUG
$936M
$18.7M 0.05%
431,873
-12,509
-3% -$535K
PJAN icon
248
Innovator US Equity Power Buffer ETF January
PJAN
$1.43B
$18.7M 0.05%
397,178
+54,042
+16% +$2.5M
IVW icon
249
iShares S&P 500 Growth ETF
IVW
$77.6B
$18.4M 0.05%
149,238
+7,118
+5% +$871K
VOT icon
250
Vanguard Morningstar Mid-Cap Growth ETF
VOT
$19.8B
$18.4M 0.05%
65,824
+17,218
+35% +$4.93M
8 9
10
11 12

Similar funds

SAM
Storebrand Asset Management Lysaker, Norway $34.8B AUM 25.49% 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
First Manhattan
First Manhattan New York $36.1B AUM 11.5% 1-Year Est. Return

William Blair & Company's Q4 2025 Portfolio in Review

As of Q4 2025, William Blair & Company held 1,963 positions worth $37.3B, down 0.82% from $37.6B the previous quarter. Its ten largest holdings account for 27% of the portfolio.

William Blair & Company's Q4 2025 filing shows 120 new, 759 increased, 753 reduced and 96 closed positions. Its largest new stake was Wingstop: 90,773 shares worth $21.6M. The largest sale was Fiserv Inc, an estimated $114M.

By sector, the portfolio is most concentrated in Technology at 26% of assets, down from 27% a quarter earlier, followed by Financials and Industrials.

  • William Blair & Company's largest Q4 2025 buy was Wingstop: 90,773 shares worth $21.6M.
  • William Blair & Company added most to BWX Technologies in Q4 2025, an estimated $46.6M increase.
  • William Blair & Company's biggest Q4 2025 reduction was Fiserv Inc, cutting an estimated $114M.
  • William Blair & Company fully exited SAP in Q4 2025, selling an estimated $9.19M.
  • William Blair & Company's ten largest holdings make up 27% of its $37.3B portfolio in Q4 2025.
  • William Blair & Company opened 120 new positions and closed 96 in Q4 2025.
  • William Blair & Company's portfolio value fell 0.82% quarter-over-quarter to $37.3B.

Based on William Blair & Company's 13F filing for Q4 2025, filed 17 Feb 2026.