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WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC

Position in ARGX — Argenx SE

CIK 1644956 CHICAGO, IL

Position in ARGX

as of Jun 30, 2026 · filed Aug 12, 2026
Position Value
$245,503,714
+$51,208,288 QoQ
Shares Held
264,617
-0.5% QoQ
Ownership
0.426%
of shares outstanding
% of Portfolio
0.75%
of 13F equity value
Holder Rank
#17
of 505 holders
Holding Since
Dec 2025
3 quarters on record
Voting authority Sole 81% Shared 0% None 19%

Common Shares in ARGX Over Time

Shares Held

Position Value (USD)

Position in Biotechnology

Healthcare · as of Jun 30, 2026

WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC holds $1,561,504,374 across 14 Biotechnology names. ARGX ranks #1 (15.7% of the industry book) .

# Ticker Company Shares Value (USD) Open
1 ARGX
Argenx SE
This page
264,617 $245,503,714

All Filings in ARGX

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3 filing rows on record
Report Date Value (USD) Shares
2026-06-30 $245,503,714 264,617
2026-03-31 $194,295,426 266,067
2025-12-31 $188,091,922 223,666