FINRA named Robert W. Cook, an attorney and former SEC director, as a replacement for the regulator's retiring CEO Richard Ketchum.

From 2010 to 2013, Cook served as director of the Division of Trading and Markets at the SEC, where he oversaw 250 employees responsible for oversight of securities exchanges, markets and FINRA, according to the regulator.

In 2013, Cook became a partner at Cleary Gottlieb Steen & Hamilton, a New York-based law firm with 1,200 lawyers practicing in 50 countries, according to the firm's website. He has been based in the law firm's Washington office where his focus is on regulation of securities markets, according to FINRA.

(Image: Bloomberg News)
Robert W. Cook, center, will replace Richard Ketchum, right, as CEO FINRA later this year. (Image: Bloomberg News)

FINRA Lead Governor Jack Brennan, a former CEO of Vanguard Group, said in a statement that the board of governors chose Cook in part because of "deep understanding of the securities markets."

Cook will only be the third person to head FINRA since its founding in 2007. Ketchum, who announced his intention to retire last year, has served as CEO and chairman of FINRA since 2009.

During that time, the regulatory scrutiny of broker-dealers has risen sharply, and not just from FINRA. In April, the Department of Labor unveiled a new fiduciary rule governing retirement advice.

In an interview earlier this year, Ketchum said that among the hurdles his successor would face is "a very crowded regulatory world."

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Pointing to the DoL rule as well as the SEC, Ketchum said that "coordination and cooperation across all regulators in order to reduce duplication is going to be a big challenge."