DOSSIER · 13F Holders · Q2 2026

BLOCK INC

10 institutions still hold BLOCK INC as of Q2 2026. Tracked across SEC 13F-HR filings, with insider and 13D/G activity surfaced alongside.

CUSIP 852234903·10 13F holders·last filed Jun 30, 2026
Market cap
13F value held
$287M
visible holders
Holders
10
filers reporting
Concentration
39.92%
IMC-Chicago, LLC #1
top holder share
AI Holders Summary · Q2 2026

10 institutions reported BLOCK INC in Q2 2026. IMC-Chicago, LLC leads at 39.9% 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
$114M1.5M0.03%Q2 2026
02
Optiver Holding B.V.
CIK 0001859606· Market maker
$99M1.3M0.03%Q2 2026
03
SIMPLEX TRADING, LLC
CIK 0001488542
$33M438K0.02%Q2 2026
04
Capital Markets Trading UK LLP
CIK 0001719165
$17M286K0.22%Q1 2026
05
GROUP ONE TRADING LLC
CIK 0000932540
$14M179K0.02%Q2 2026
06
JPMORGAN CHASE & CO
CIK 0000019617
$4M50K0.00%Q2 2026
07
Maven Securities LTD
CIK 0001633046
$3M38K0.06%Q2 2026
08
CMT Capital Markets Trading GmbH
CIK 0001632813
$3M44K0.03%Q1 2026
09
SG Americas Securities, LLC
CIK 0001313360
$48K23K0.00%Q1 2026
10
CONCOURSE FINANCIAL GROUP SECURITIES, INC.
CIK 0000752798
$00Q2 2025