There's been a shakeup at the trading venue made famous by 'Flash Boys'

IEX

The IEX team.

The firm has appointed Ronan Ryan, who was previously chief strategy officer, as president - a new role at the firm.

He will be replaced as chief strategy officer by Eric Stockland, who joins from KCG Holdings. In his previous role, he advised investors on algorithmic trading strategies.

He also previously worked at GETCO, a well-known high-frequency trading firm. IEX was made famous in part because of its effort to protect investors from high-frequency trading.

"Eric's background as an expert practitioner in electronic market-making and agency trading makes him an ideal fit for a trading venue that's striving to deliver greater efficiencies while retaining the speed and resiliency of an all-electronic marketplace," Ronan said in a statement.

IEX filed with the SEC to become a stock exchange in September. A long list of parties have sent in feedback to the SEC on the application, though KCG, Stockland's former employer, is not one of them.

The debate on the merits of the IEX application has at times gotten ugly with IEX and the New York Stock Exchange in particular trading barbs. More recently, Nasdaq's law firm, Gibson Dunn, said that the SEC could be sued if it approves IEX's application to become an exchange.

For its part, the SEC has delayed its decision on the application until June 18.