Upstart IEX takes off gloves in fight with critics

IE🐭X, the two-year-old stock trading upstart founded by Brad Katsuyama of “Flash Boys” fame, has switched from playing defense to offense.

The private trading platform, which is seeking regulatory approval to꧟ become a full-fledged exchange, is going after some of the big players that have argued against it before the Securities and Exchange Co💮mmission.

IEX posted an open letter on Sunday that claimed the New York Stock Exchange has a previously undisclosed “speed bump” that slows trad𓆉e quotes.

“They effectively slow down everyone else by offering a faster means of access that only a few have bothereไd to adopt given the amount of development work necessary to do so,” IEX co-founder Don Bollerman wrote.

A spokesman for NYSE said, “That is incorrect.”

IEX has implemented a controversial 350-microsecond delay, or “speed bump,” so that high-frequency traders can’t use their speed 🔴to “front run” slower traders. “IEX wants to play in the big leagues. We understand how the game is pla🙈yed,” one IEX executive told The Post.

Although the SEC set a deadline of Dec. 21 to act on the application submitteꦇd in September, the agency ꦗrecently has asked for another 90 days to make a decision after more than 300 parties weighed in during the comment period.

Meanwhile, IEX’s detr💟actors, including Nasdaq and NYSE and high-speed trading giant Citadel, are looking to drag out the process even longer by calling fo🍨r an overhaul of decades-old market rules.

They argue IEX will run afoul of Regulation National Market System, or Reg NMS, which 🔯states that stock trades should occur on whichever market has the best price at a given time. They are urging the SEC to conduct a comprehensive review.