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Finance · Profile from Finance Research Companion

Interactive Brokers Group, Inc.

The Greenwich, Connecticut broker built by Thomas Peterffy, a Hungarian-born programmer who bought a seat on the American Stock Exchange in 1977 and spent the next five decades replacing floor traders, back-office clerks and sales staff with software. Interactive Brokers began as Timber Hill, an options market maker that priced trades with computer models and handheld devices; it turned that technology outward in 1993 to serve professional traders, listed in a Dutch-auction IPO in 2007, quit market making in 2017, and became the lowest-cost, most automated global brokerage of its era. By September 2026 it served ~5.58 million accounts holding ~$965bn of customer equity across 160+ markets, with pre-tax margins in the high 70s per cent, far above any other broker. It is the quiet counter-example to the "free trading" story: it rarely advertises zero commissions, sells little through human advisers, and earns most of its money from the interest spread on customer cash and margin loans.

At a glance

Founded
1977–78 (Peterffy's AMEX options seat and trading business, reported); Timber Hill formed 1982; Interactive Brokers brokerage launched 1993
Headquarters
One Pickwick Plaza, Greenwich, Connecticut; large operations in Chicago, Hong Kong, Budapest, Zug, Mumbai and elsewhere
Ownership / structure
Interactive Brokers Group, Inc. (Nasdaq: IBKR), a holding company whose main asset is a stake in IBG LLC; Thomas Peterffy and employees own most of IBG LLC through IBG Holdings LLC, and the public float has risen gradually since the 2007 IPO (company)
Leadership (2026)
Thomas Peterffy, founder and chairman; Milan Galik, CEO (since October 2019); Paul Brody, CFO
Segment
Exchange & infrastructure / fintech: global electronic broker-dealer and futures commission merchant (stocks, options, futures, FX, bonds, funds, crypto, forecast contracts); clearing for introducing brokers and advisers
Scale (Q3 2026)
~5.58m customer accounts (+35% y/y); customer equity ~$964.7bn (+27%); customer credit balances ~$186.2bn; margin loans ~$105.2bn (company, 15 October 2026)
Profit
2025: net revenues >$6bn (first time; ~$6.2bn reported), record pre-tax margin ~77%, commissions ~$2.1bn, net interest income ~$3.6bn (company, January 2026)
Index
Joined the S&P 500 on 28 August 2025, replacing Walgreens Boots Alliance (S&P Dow Jones Indices)
Signature moves (incl. failures)
AMEX seat and Timber Hill (1977–82); launch of Interactive Brokers (1993); Dutch-auction IPO (2007); Swiss franc shock loss (2015); exit from market making (2017); IBKR Lite (2019); AML settlements (2020) and OFAC settlement (2025); GameStop restrictions (2021); ForecastEx prediction markets (2024); S&P 500 entry and record growth (2025–26)

10 strategic moves analysed

Each one gets a full strategy file in the companion: context, the decision, the financing, what happened, and the lesson.

  1. 1977

    AMEX Seat and Timber Hill

    Founding

  2. 1993

    Interactive Brokers Electronic Brokerage Launch

    Launch

  3. 2007

    Dutch Auction IPO

    IPO

  4. 2015

    Swiss Franc Shock Losses

    Failure (customer credit loss)

  5. 2017

    Exit from Market Making

    Divestiture / pivot

  6. 2019

    IBKR Lite Zero Commissions

    Pricing change / launch

  7. 2020

    AML Failures and 38m Settlements

    Regulatory settlement

  8. 2021

    GameStop Restrictions and Peterffy Warning

    Risk action / controversy

  9. 2024

    ForecastEx Prediction Markets

    Launch

  10. 2025

    S and P 500 Entry and Record Growth

    Growth / milestone (index inclusion, stock split, stablecoin funding, dividend increase)