DOSSIER · 13F Holders · Q3 2026

WESTERN DIGITAL CORP

8 institutions still hold WESTERN DIGITAL CORP as of Q3 2026. Tracked across SEC 13F-HR filings, with insider and 13D/G activity surfaced alongside.

CUSIP 958102955·8 13F holders·last filed Sep 30, 2026
Market cap
—
13F value held
$1.6B
visible holders
Holders
8
filers reporting
Concentration
71.40%
IMC-Chicago, LLC #1
top holder share
AI Holders Summary · Q3 2026

8 institutions reported WESTERN DIGITAL CORP in Q3 2026. IMC-Chicago, LLC leads at 71.4% of the visible book.

Top holders

Sorted by position value. Source: SEC EDGAR 13F-HR filings.

#HolderValueShares% port.Quarter
01
IMC-Chicago, LLC
CIK 0001452861· Market maker
$1.1B2.5M0.23%Q3 2026
02
NATIONAL BANK OF CANADA /FI/
CIK 0000926171
$240M4K0.17%Q2 2026
03
SIMPLEX TRADING, LLC
CIK 0001488542
$110M248K0.06%Q3 2026
04
GROUP ONE TRADING LLC
CIK 0000932540
$54M118K0.07%Q3 2026
05
JPMORGAN CHASE & CO
CIK 0000019617
$41M91K0.00%Q3 2026
06
CMT Capital Markets Trading GmbH
CIK 0001632813
$8M29K0.08%Q1 2026
07
AlphaCore Capital LLC
CIK 0001713662
$201K300.00%Q3 2026
08
CONCOURSE FINANCIAL GROUP SECURITIES, INC.
CIK 0000752798
$00—Q2 2025