According to WSJ, the SEC staff recommended the company win its bid to become an exchange. That suggests that IEX will win full approval when the SEC's commissioners vote on the matter Friday.

IEX had no comment on the report.

IEX in September filed with the SEC to become a stock exchange, triggering an ugly war of words between its backers and its enemies.

Opponents of IEX's plan say that approving the application could destabilize the stock market. They include the New York Stock Exchange and Nasdaq, which - through its law firm - said that the SEC could be sued if it approves IEX's application.