DOSSIER · 13F Holders · Q3 2026

COMFORT SYS USA INC

5 institutions still hold COMFORT SYS USA INC as of Q3 2026. Tracked across SEC 13F-HR filings, with insider and 13D/G activity surfaced alongside.

CUSIP 199908904·5 13F holders·last filed Sep 30, 2026
Market cap
—
13F value held
$185M
visible holders
Holders
5
filers reporting
Concentration
88.73%
IMC-Chicago, LLC #1
top holder share
AI Holders Summary · Q3 2026

5 institutions reported COMFORT SYS USA INC in Q3 2026. IMC-Chicago, LLC leads at 88.7% 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
$164M99K0.03%Q3 2026
02
SIMPLEX TRADING, LLC
CIK 0001488542
$16M10K0.01%Q3 2026
03
GROUP ONE TRADING LLC
CIK 0000932540
$4M3K0.01%Q3 2026
04
CI INVESTMENTS INC.
CIK 0001163648
$510K500.00%Q3 2026
05
CONCOURSE FINANCIAL GROUP SECURITIES, INC.
CIK 0000752798
$00—Q2 2025