15. Rob Park
Chief Technology Officer
IEX Group
Last year: 16

Then an upstart alternative trading system, IEX Group was portrayed as an anti-establishment disrupter in Michael Lewis's 2014 best-seller Flash Boys. Now it is a full-fledged exchange business — IEX obtained Securities and Exchange Commission approval last June for the Investors Exchange, which went live in August. It's still taking potshots from the equity market establishment as its market share hovers around 2 percent. A distinguishing feature, built into the infrastructure overseen by chief technology officer Rob Park, is a 350-microsecond speed bump designed to enforce the IEX ideal of a "fair, simple, and transparent stock exchange" protective of long-term investors' interests. In practice the bump prevents high frequency traders from taking advantage of fleeting delays in exchanges' price updates — known as latency arbitrage, which Park, 38, calls "an invisible tax on the investment process."

A member of the IEX founding team, led by CEO Brad Katsuyama, that came out of RBC Capital Markets, Park was previously co-founder of Quantera Financial Corp., a proprietary high frequency trading firm that specialized in statistical and machine learning algorithms. He and Katsuyama are board members of TradeWind Markets, an IEX technology spin-off that raised $9 million in funding last year to develop a blockchain-based gold marketplace.

The 2017 Trading Tech 40
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