BLAIR WILLIAM & CO/ILBLAIR WILLIAM & CO/IL

Institutional investor · Portfolio as of Q1 2026

SEC EDGAR SourceSEC Filings

Top Holdings1,922 positions

Activity:
Stock
Shares
Value
Weight
Avg Buy
Est. P&L
Held
Conviction

APPLE INC

5.9M$1.5B4.3%$102.27+208.32%
30 qtrssince 2018-Q4
Decreased
0

MICROSOFT CORP

3.5M$1.3B3.7%$123.66+211.42%
30 qtrssince 2018-Q4
Decreased
0

AMAZON COM INC

6.1M$1.3B3.6%$114.59+114.11%
30 qtrssince 2018-Q4
Decreased
0

NVIDIA CORPORATION

5.4M$946.6M2.7%$118.12+78.60%
30 qtrssince 2018-Q4
Decreased
0

ALPHABET INC

3M$870.8M2.5%$95.36+272.31%
30 qtrssince 2018-Q4
Decreased
0

ALPHABET INC

2.4M$700.5M2.0%$101.51+251.87%
30 qtrssince 2018-Q4
Decreased
0

JPMORGAN CHASE & CO

2.3M$678.7M1.9%$105.79+218.05%
30 qtrssince 2018-Q4
Decreased
0

GE VERNOVA INC

664,603$580.1M1.7%$407.51+167.87%
8 qtrssince 2024-Q2
Increased
50

VISA INC

1.8M$557.5M1.6%$132.86+162.66%
30 qtrssince 2018-Q4
Decreased
0
SPYSPY
Unit

State Street Spdr S&p 500 Etf Trust TR UNIT

845,294$549.7M1.6%$325.26+132.11%
30 qtrssince 2018-Q4
Decreased
0

IDEXX LABS INC

946,336$531.7M1.5%$189.63+197.19%
30 qtrssince 2018-Q4
Decreased
0

COSTCO WHOLESALE CORPORATION

521,277$519.4M1.5%$312.76+192.96%
30 qtrssince 2018-Q4
Increased
49

MASTERCARD INCORPORATED

923,405$461.4M1.3%$200.68+162.47%
30 qtrssince 2018-Q4
Decreased
0

META PLATFORMS INC

721,720$412.9M1.2%$457.25+46.35%
30 qtrssince 2018-Q4
Decreased
0

FASTENAL CO

7.4M$342.1M1.0%$29.07+59.90%
30 qtrssince 2018-Q4
Increased
46
RSPRSP
ETF

INVESCO EXCHANGE TRADED FD T

1.7M$322.5M0.9%$188.92+13.44%
30 qtrssince 2018-Q4
Increased
70

AMPHENOL CORP

2.5M$318.4M0.9%$46.48+242.20%
30 qtrssince 2018-Q4
Decreased
0
IVVIVV
ETF

iShares Trust CORE S&P500 ETF

485,839$317.4M0.9%$384.47+97.18%
30 qtrssince 2018-Q4
Decreased
0
VEUVEU
ETF

VANGUARD INTL EQUITY INDEX F

4.2M$313.1M0.9%$61.35+36.11%
30 qtrssince 2018-Q4
Increased
61

ELI LILLY & CO

324,018$298M0.9%$265.19+348.21%
30 qtrssince 2018-Q4
Decreased
0
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$34.9B
AUM
1,922
Positions
Q1 2026
Filing
Rating · 4.5
Quarterly Portfolio Change
+1%Q4'24$34.4B-4%Q1'25$33.2B+9%Q2'25$36B+4%Q3'25$37.6B-1%Q4'25$37.3B-6%Q1'26$34.9B
Activity profile
$ moved · Q1'26
New1%Increased35%Decreased63%Exited1%
Composition
Equity vs derivatives
Equity100%Puts0%Calls0%
Holding period
Avg 5.3 years
<1Q5%1-4Q7%1-2Y6%2Y+82%

BLAIR WILLIAM & CO/IL manages $34.9B across 1922 positions as of Q1 2026. Top holdings: AAPL (4.3%), MSFT (3.7%), AMZN (3.6%). Fund DNA: Balanced Allocator. HoldingsIntel Rating: 4.5/5.0.

Q1 2026 Summary

Active quarter - 151 new positions, 99 exits, 799 increased. Top move: RSP (INCREASED, conviction 70). Portfolio: $34.9B across 1922 positions.

Top holdings by portfolio weight

Total AUM$35B
AAPL4.31%
MSFT3.71%
AMZN3.62%
NVDA2.71%
GOOG2.50%
GOOGL2.01%
JPM1.94%
GEV1.66%
V1.60%
SPY1.58%
Other1.52%

Portfolio allocation by GICS sector

Sectors11
Technology21.75%
Unknown17.51%
Industrials14.21%
Financial Services12.27%
Healthcare10.60%
Consumer Cyclical7.18%
Communication Services7.02%
Consumer Defensive4.05%
Energy2.15%
Basic Materials1.74%
Other1.52%

Behavioral investing profile

7-dimension quality assessment
Elite(4.5 / 5.0)
Track Record66
Conviction38
Concentration39
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Position Outcomes

Best and worst performing positions by estimated return

Cost basis estimates based on full filing history using quarter-end prices. Actual transaction prices are not disclosed in 13F filings.

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Accumulation Streaks

Positions with 2+ consecutive quarters of increases - persistent directional conviction.

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7Q
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7Q
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Data sourced from SEC EDGAR 13F filings. Not financial advice. Full disclaimer

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