DOSSIER · 13F Holders · Q3 2026

ATLASSIAN CORPORATION

6 institutions still hold ATLASSIAN CORPORATION as of Q3 2026. Tracked across SEC 13F-HR filings, with insider and 13D/G activity surfaced alongside.

CUSIP 049468951·6 13F holders·last filed Sep 30, 2026
Market cap
—
13F value held
$142M
visible holders
Holders
6
filers reporting
Concentration
67.07%
IMC-Chicago, LLC #1
top holder share
AI Holders Summary · Q3 2026

6 institutions reported ATLASSIAN CORPORATION in Q3 2026. IMC-Chicago, LLC leads at 67.1% 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
$95M531K0.02%Q3 2026
02
GROUP ONE TRADING LLC
CIK 0000932540
$20M111K0.03%Q3 2026
03
SIMPLEX TRADING, LLC
CIK 0001488542
$15M85K0.01%Q3 2026
04
Optiver Holding B.V.
CIK 0001859606· Market maker
$8M101K0.00%Q2 2026
05
Maven Securities LTD
CIK 0001633046
$4M50K0.08%Q2 2026
06
CONCOURSE FINANCIAL GROUP SECURITIES, INC.
CIK 0000752798
$00—Q2 2025