13F Insight
DOSSIER · 13F-HR · Q3 2026

BLAIR WILLIAM & CO/IL

$38.6B in tracked AUM across 2,029 positions as of Q3 2026.

BW
CIK 0000902367 · last filed Sep 30, 2026
Total AUM
$38.6B
as of Q3 2026
Holdings
2,029
—
positions
Whale Score
65
65
tracked
Activity
—
no data
changes this Q
AI Analysis · Q3 2026

Portfolio Overview

Blair William & Co. manages a substantial, diversified equity portfolio valued at approximately $37.57 billion as of September 30, 2025. The firm experienced a positive quarter, growing assets under management by 4.4% from the previous quarter's $36.00 billion. The portfolio is highly diversified, encompassing 1,844 individual holdings. Despite the large number of positions, the firm employs a core-satellite approach where a significant portion of the capital is concentra...

Key Holdings

The portfolio is anchored by mega-cap technology leaders, which dominate the top rankings. Microsoft (MSFT) is the largest holding at $1.87 billion (4.97% of the portfolio), followed closely by Apple (AAPL) at $1.53 billion (4.06%) and Amazon (AMZN) at $1.32 billion (3.51%). These three companies alone constitute over 12.5% of the total assets, indicating a strong conviction in the dominant U.S. technology franchises.

Analysis generated by 13F Insight from SEC Form 13F filing data · Q3 2026. Methodology

Quarter at a glance — Q3 2026

Position-change comparison pending.

No quarter-over-quarter changes available.

Top 10 holdings

By portfolio weight as of Q3 2026. Source: SEC EDGAR 13F-HR filings.

#HoldingValueSharesWeight
01
AAPL
APPLE INC
$1.9B5.7M4.9%02
MSFT
MICROSOFT CORP
$1.7B3.4M4.5%03
AMZN
AMAZON COM INC
$1.4B5.7M3.7%04
NVDA
NVIDIA CORPORATION
$1.2B5.4M3.2%05
GOOG
ALPHABET INC
$989M2.9M2.6%06
GOOGL
ALPHABET INC
$808M2.3M2.1%07
JPM
JPMORGAN CHASE & CO
$750M2.3M1.9%08
V
VISA INC
$650M1.8M1.7%09
SPY
STATE STR SPDR S&P 500 ETF T
$643M843K1.7%10
GEV
GE VERNOVA INC
$610M642K1.6%

Filing history

2026Q3Sep 30
$38.6B▲ 0.5%
2,029 positionsView →2026Q2Jun 30
$38.4B▲ 10.0%
2,054 positionsView →2026Q1Mar 31
$34.9B▼ 6.3%
1,922 positionsView →2025Q4Dec 31
$37.3B▼ 0.8%
1,920 positionsView →2025Q3Sep 30
$37.6B▲ 4.4%
1,844 positionsLocked2025Q2Jun 30
$36.0B▲ 8.6%
1,824 positionsLocked2025Q1Mar 31
$33.2B▼ 3.6%
1,801 positionsLocked2024Q4Dec 31
$34.4B▲ 1.0%
1,816 positionsLocked2024Q3Sep 30
$34.1B▲ 5.0%
1,821 positionsLocked2024Q2Jun 30
$32.4B▲ 1.8%
1,822 positionsLocked2024Q1Mar 31
$31.8B▲ 8.5%
1,787 positionsLocked2023Q4Dec 31
$29.3B▲ 12.5%
1,785 positionsLocked
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