Citadel Securities Loses Flash-Boys Legal Fight Over IEX Product

Citadel Securities LLC lost its case against the SEC over a market order type from the IEX exchange of “Flash Boys” fame that features a 350-microsecond delay, after arguing the regulator botched its approval.

A trio of federal judges in Washington on Friday upheld the US Securities and Exchange Commission’s decision on the order type, the exchange operator’s D-Limit, whose delay is meant to reduce the advantage of high-frequency traders. The electronic trading firm founded by billionaire Ken Griffin argued that D-Limit hurts investors by delaying their orders and that the SEC approval process broke the laws and rules ...