Custom Index Systems, LLC

SEC CIK: 0002003672
Latest filing: Aug 14, 2026

SEC filings (opens in a new tab)

IBKR holding history

Interactive Brokers Group, Inc. in every 13F filed by Custom Index Systems, LLC, including the quarters it was sold out or no filing was made. Changes compare share counts with the previous calendar quarter.

IBKR overview All 13F holders of IBKR Full Q2 2026 holdings

Shares (Q2 2026): 6,991
Value: $608.5K
% of portfolio: 0.2%
Quarters held: 4; Since Q3 2025

Holdings of IBKR by Custom Index Systems, LLC, by quarter
Quarter	Shares	Value	% of portfolio	Share change	Action	All holders
Q2 2026	6,991	$608.5K	0.2%	+148+2.2%	Added	Holders
Q1 2026	6,843	$459.0K	0.2%	−274−3.8%	Reduced	Holders
Q4 2025	7,117	$457.7K	0.2%	−4,640−39.5%	Reduced	Holders
Q3 2025	11,757	$809.0K	0.2%	+11,757	New	Holders