Who Owns Interactive Brokers?
Interactive Brokers is effectively still owned by its founder, Thomas Peterffy. Interactive Brokers Group, Inc. (IBKR) is a publicly traded holding company that acts as the sole managing member of the operating partnership, IBG LLC. The remaining non-public ownership of IBG LLC is held by IBG Holdings LLC, an entity controlled by Peterffy and company insiders.
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Here are the major milestones in Interactive Brokers’ history from an ownership perspective:
Make Full Width| Year | Milestone | Corporate Entity | Ownership & Voting Control |
|---|---|---|---|
| 1977 | Sole Proprietorship | Independent AMEX Seat | 100% Founder-Owned – Thomas Peterffy purchases a seat on the American Stock Exchange (AMEX) for $36,000 to trade equity options as an individual market maker. |
| 1978 | Formation of T.P. & Co. | T.P. & Co. | 100% Privately Held – Peterffy establishes T.P. & Co. to expand floor trading operations to multiple exchange members under badge 549. |
| 1982 | Incorporation of Timber Hill | Timber Hill Inc. | 100% Privately Held – T.P. & Co. is renamed and incorporated as Timber Hill Inc., owned by Peterffy and key early employee partners. |
| 1993–1994 | Creation of IBG LLC & Interactive Brokers | IBG LLC / Interactive Brokers LLC | 100% Privately Held – IBG LLC is created as the master holding company. Interactive Brokers LLC is established to separate electronic brokerage from Timber Hill’s market-making operations. |
| May 2007 | Initial Public Offering (IPO) | Interactive Brokers Group, Inc. (NASDAQ: IBKR) | 10% Public / 90% Insider Control – IBKR Inc. held a ~10% managing interest in IBG LLC, while IBG Holdings LLC retained ~90%. Class B shares gave Peterffy ~95% total voting control. |
| 2018 | Exchange Relisting & Equity Conversion | IBKR moves to IEX (later returned to Nasdaq) | ~18–20% Public / ~80–82% Insider Control – Through annual redemptions, IBG Holdings LLC periodically converted membership units into Class A public shares, slowly expanding the public float. |
| 2019 | CEO Succession | Management Transition | Founder Voting Control Preserved – Thomas Peterffy steps down as CEO (succeeded by Milan Galik), but remains Chairman and controlling shareholder through IBG Holdings LLC. |
| 2025–Present | S&P 500 Inclusion & Modern Structure | Interactive Brokers Group, Inc. (Ticker: IBKR) | ~26% Public / ~73% Insider Control – Public Shareholders (IBKR Class A) hold 26% of IBG LLC, while IBG Holdings LLC holds 73% and retains majority voting power via Class B stock. |
Can Public Shareholders Control Interactive Brokers?
No. While anyone can buy IBKR shares, control sits firmly with its 80-something founder, who remains chairman. This means he can heavily influence director appointments and major corporate decisions. Public investors own a minority of the company’s economic interest and voting power.
That founder-led continuity, however, is part of why the firm has stuck to its low-cost, tech-first approach for decades.