DOSSIER · 13F-HR · Q1 2026

BLAIR WILLIAM & CO/IL

BLAIR WILLIAM & /IL's family office based in New York, NY $34.9B in tracked AUM across 1,922 positions as of Q1 2026.

BW
BLAIR WILLIAM & /IL·New York, NY·Family Office
CIK 0000902367 · last filed Mar 31, 2026
Total AUM
$34.9B
13.6%
vs prior
Holdings
1,922
positions
Whale Score
60
60
tracked
Activity
no data
changes this Q
Top sector
Tech
6% weight
concentration
AI Analysis · Q1 2026 · Q1 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...

Quarter at a glance — Q1 2026

Position-change comparison pending.

No quarter-over-quarter changes available.

Top 10 holdings

By portfolio weight as of Q1 2026.

#HoldingValueSharesWeight
01
AAPL
APPLE INC
$1.5B5.9M4.3%
02
MSFT
MICROSOFT CORP
$1.3B3.5M3.7%
03
AMZN
AMAZON COM INC
$1.3B6.1M3.6%
04
NVDA
NVIDIA CORPORATION
$947M5.4M2.7%
05
GOOG
ALPHABET INC
$871M3.0M2.5%
06
GOOGL
ALPHABET INC
$701M2.4M2.0%
07
JPM
JPMORGAN CHASE & CO
$679M2.3M1.9%
08
GEV
GE VERNOVA INC
$580M665K1.7%
09
V
VISA INC
$558M1.8M1.6%
10
SPY
STATE STR SPDR S&P 500 ETF T
$550M845K1.6%

Filing history

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