Interactive Brokers

Thomas Peterffy was born in Budapest in 1944 and emigrated to the United States in 1965 with $2,200 in savings. He taught himself English by watching TV and trained as a draftsman before teaching himself computer programming. In 1977, he bought a seat on the American Stock Exchange — at the time, options trading was dominated by human market makers shouting on the trading floor. Peterffy saw something others missed: options pricing was a mathematical problem, and computers were better at mathematics than human traders. He built his own pricing models and began trading.

In 1983, Peterffy built what may have been the first handheld computer used on an exchange trading floor — a device that calculated options prices in real time and fed them to his market-making team. Exchange rules required quotes to be delivered verbally; Peterffy's team used the computer to calculate prices and then shouted them out. The exchange eventually ruled that the device violated rules by displaying prices electronically; Peterffy challenged the ruling and ultimately convinced regulators that electronic pricing was the future of trading. The episode established the principle that would define Interactive Brokers: technology always beat human intuition in markets.

Peterffy's firm, Timber Hill, built one of the first fully automated, electronic market-making systems in the world, eliminating the need for human traders on the floor entirely. The system could process thousands of options contracts across hundreds of securities simultaneously, adjusting prices in milliseconds in response to market movement. The technology that other market participants found threatening, Peterffy pursued relentlessly. Interactive Brokers was founded in 1993 as the retail and institutional brokerage arm, offering access to markets globally through technology that had been developed for Timber Hill's own trading.

Interactive Brokers went public in May 2007 at a $10 billion valuation. The company had built something genuinely unique: a single brokerage account that provided access to stocks, options, futures, forex, bonds, and funds on over 150 markets in 33 countries and 25 currencies — more markets, more asset classes, and more technical sophistication than any retail or institutional competitor. Peterffy retained approximately 80% of the company after IPO, maintaining absolute control. The low commission structure and professional-grade tools attracted active traders, hedge funds, institutions, and quantitative firms who valued access over simplicity.

Interactive Brokers reported record revenues of $4.7 billion for fiscal year 2024, driven by rising interest income on client cash balances as interest rates rose. The company's market capitalisation exceeded $50 billion. In 2025, IBKR entered the prediction markets category with ForecastTrader — giving its professional client base access to event contracts alongside their existing multi-asset trading. Peterffy, now in his 80s, remained the company's controlling shareholder and philosophical anchor, still advocating for technology, low costs, and access over simplicity. The Hungarian immigrant who had arrived with $2,200 had built a $50 billion financial technology company.