Interactive Brokers Group, Inc.
MX ˙ BMV ˙ US45841N1072
SecurityMX:IBKR / Interactive Brokers Group, Inc.
InstitutionO'Brien Greene & Co. Inc
Latest Disclosed Ownership252,741 shares
Latest Disclosed Value $ 16,951,324
O'Brien Greene & Co. Inc reports 2.53% decrease in ownership of IBKR / Interactive Brokers Group, Inc.

On May 6, 2026 - O'Brien Greene & Co. Inc filed a 13F-HR form disclosing ownership of 252,741 shares of Interactive Brokers Group, Inc. (MX:IBKR) valued at $16,951,324 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 5, 2026 disclosing 259,303 shares of Interactive Brokers Group, Inc.. This represents a change in shares of -2.53% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel .

Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-06 2026-03-31 13F Interactive Brokers Group COM 45841N107 252,741 -6,562 -2.53 16,951 1.66 2.7047
2026-02-05 2025-12-31 13F Interactive Brokers Group COM 45841N107 259,303 -8,832 -3.29 16,676 -9.62 4.9506
2025-11-10 2025-09-30 13F Interactive Brokers Group COM 45841N107 268,135 -13,554 -4.81 18,450 18.21 5.6741
2025-08-06 2025-06-30 13F Interactive Brokers Group COM 45841N107 281,689 208,961 287.32 15,608 29.60 5.1053
2025-05-12 2025-03-31 13F Interactive Brokers Group COM 45841N107 72,728 -3,183 -4.19 12,043 -10.20 4.0400
2025-02-03 2024-12-31 13F Interactive Brokers Group COM 45841N107 75,911 -5,807 -7.11 13,411 17.76 4.3542
2024-11-15 2024-09-30 13F Interactive Brokers Group COM 45841N107 81,718 -4,763 -5.51 11,388 7.41 3.5462
2024-08-12 2024-06-30 13F Interactive Brokers Group COM 45841N107 86,481 -600 -0.69 10,603 9.00 3.3577
2024-05-02 2024-03-31 13F Interactive Brokers Group COM 45841N107 87,081 931 1.08 9,728 36.21 3.1984
2024-02-02 2023-12-31 13F Interactive Brokers Group COM 45841N107 86,150 630 0.74 7,142 -3.53 2.5114
2023-11-08 2023-09-30 13F INTERACTIVE BROKERS GROUP COM 45841N107 85,520 1,352 1.61 7,403 123,266.67 2.7078
2023-08-15 2023-06-30 13F/A-1 INTERACTIVE BROKERS GROUP COM 45841N107 84,168 27,056 47.37 7 50.00 2.4305
2023-07-20 2023-06-30 13F INTERACTIVE BROKERS GROUP COM 45841N107 250,854 193,742 21 2.4300
2023-05-03 2023-03-31 13F INTERACTIVE BROKERS GROUP COM 45841N107 57,112 400 0.71 5 0.00 1.7662
2023-02-02 2022-12-31 13F INTERACTIVE BROKERS GROUP COM 45841N107 56,712 56,712 4 1.5560
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.