10. Raj Mahajan
Co-head of Global Execution Services
Goldman Sachs Group
Last year: 9

Two years ago Raj Mahajan came into Goldman Sachs Group as a partner. That was a sign of the firm's regard for Mahajan and his trading technology background as he took on the role of global head of equities electronic execution services. A year ago he was named co-head of global execution services; he told Reuters at the time that "simply put, we want to deliver the best execution quality to our clients, which is tantamount to saying we need the best technology."

Mahajan, 44, had worked as an analyst at Goldman early in his career, and he returned as a successful technologist and entrepreneur. In 2000 he co-founded — with former Goldman chief information officer and now CFO-designate R. Martin Chavez — Kiodex, a developer of commodity-trading systems. SunGard Data Systems bought the start-up in 2004, and Mahajan went with it, rising over eight years with SunGard to president of its global trading business. In 2012 he became CEO of Allston Trading, a high frequency firm based in Chicago. When Goldman hired him and brought him back to New York in 2015, it described him in a memo as "bringing extensive experience in electronic trading, market structure, technology, and entrepreneurship to our rapidly growing electronic execution franchise. He will be responsible for delivering innovative electronic execution solutions to global clients across equity products worldwide."

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