(Changes attribution for information, adds details on market conditions)
April 17 (Reuters) - High-speed trading firm Virtu Financial Inc has not set a date to go to market with its initial public offering at this time, according to a person familiar with the matter.
The move comes as high-frequency trading (HFT) is under intense scrutiny, following the release of author Michael Lewis' book "Flash Boys: A Wall Street Revolt".
Shares of KCG Holdings, a firm that engages in electronic market making practices similar to Virtu, are down 16.7 percent since the beginning of April.
Adverse market conditions have also plagued the IPO market in recent weeks, the person said, who was not authorized to speak publicly on the matter.
Virtu's IPO, which was expected in April, was seeking to raise about $200 million to $250 million, valuing the firm at about $3 billion.
Reuters reported earlier this month that Virtu delayed the launch of its IPO as it awaited regulatory approval, which was expected within days rather than weeks.
Virtu, one of the biggest U.S. HFT firms, is active in making markets on IEX, taking the other side of trades to ensure the market stays liquid.
(Reporting by Avik Das in Bangalore and Mike Stone in New York; Editing by Sriraj Kalluvila, Bernard Orr)