In 1982, physicist William A. Porter and Bernard A. Newcomb founded TradePlus in Palo Alto, California, with $15,000 in capital.

[5][6][7] In November 2007, Mitch Caplan resigned as CEO and Citadel LLC received a seat on the board of directors of the company after Citadel invested $2.5 billion in the company to bolster its finances after it suffered losses due to the bursting of the 2000s United States housing bubble.

[11][12][13] In December 2009, Robert Druskin, a former chief operating officer of Citigroup, was named interim CEO and chairman.

Freiberg was the former co-CEO of Citigroup's global consumer group and the former head of its credit card unit.

Idzik had previously been group chief executive of DTZ and also served ten years at Barclays bank.