In 1977, he purchased a seat on the American Stock Exchange and played a role in developing the first electronic trading platform for securities.

Peterffy left his engineering studies in Hungary and emigrated to the United States to join his father in New York in 1965.

[6][7] Peterffy left his career designing financial modeling software and bought a seat on the American Stock Exchange to trade equity options.

The Budapest-based subsidiary, Interactive Brokers Central Europe Zrt., was established in Hungary and became a member of the Budapest Stock Exchange (BSE) upon its incorporation.

[11][12] Peterffy, alongside Mark Penn, Victor Ganzi, Josh Harris, and James Tisch, contributed to a $50 million investment fund in The Messenger, a news website that launched in May 2023.

[6] During the 2012 United States presidential campaign, Peterffy created political ads supporting the Republican Party.

[16] Peterffy bought millions of dollars of air time on networks such as CNN, CNBC, and Bloomberg.

The ads consisted of a minute-long spot narrated by Peterffy, warning against creeping socialism in the United States.

Joshua Green, writing for Bloomberg Businessweek, said "The ad, while slightly ridiculous, is deeply sincere and also quite affecting."

[17] He donated over $60,000 to the Republican National Committee in 2011 and $100,000 to a pro-Donald Trump political group during the 2016 United States presidential election.

[27] In November of 2022, Peterffy had said that Trump, "can't get elected" and that, even if as a citizen he would vote for him as the GOP nominee, that he, "will do whatever I can to make sure he is not.

"[28] However, as events unfolded, and voters across America continued to support Trump, wealthy Republican donors, including Peterffy, who had distanced themselves from him earlier, began to change their minds.

[32][33][34] On December 11, 2024, in the aftermath of the election, Peterffy sat down for an interview with Bloomberg's Sonali Basak at a Goldman Sachs Group Inc. conference.

The company traces its origin to 1977 when Peterffy bought a seat on the American Stock Exchange as an individual market maker and formed T.P.

IB has many subsidiaries operating on most major stock, futures, bonds, forex, and options exchanges worldwide.

OneChicago offered approximately 2,272 single-stock futures (SSF) products[41] with names such as IBM, Apple and Google.