Barclays dark pool concerns raised months before lawsuit

Concerns had been raised months before the New York attorney general alleged in June that Barclays lied to clients about the extent of predatory trading activity on the electronic trading venue,The Wall Street Journal reported on Monday.Stocks in Barclays slid as sources told the newspaper that trading firms and employees had voiced worries about the high-speed traders at the bank well before New York Attorney General Eric Schneiderman's complaint.The sources said some big trading outfits noticed their orders weren't getting the best treatment on the dark pool and that the firms had grown concerned that the poor results resulted from high-frequency trading.Dark pools allow large blocks of shares to be traded anonymously without informing the market until completion to minimise the risk of the price moving to the disadvantage of an investor should the market find out about the trade before it is finalised.Schneiderman's lawsuit, filed on June 25th, claims that Barclays lied to clients and gave high-frequency traders an unfair advantage.Shares closed down 0.76% at 210.20p following the news.RD