Barclays is likely to be subject to a lawsuit from the New York Attorney General related to alleged fraud in the bank's 'dark pool' equity-trading business.According to unnamed sources briefing the media, cited as a person familiar with the matter, the legal case will allege fraudulent activity at Barclays market-leading 'dark pool' stock-trading network, an institutional-only service where traders can conduct deals anonymously at prices that are only visible at the conclusion of the trade. The lawsuit is expected to allege that the Barclays' Wall Street dark pool gave high-frequency traders advantages over other customers, The suit is expected to allege that the firm's dark pools and false advertising.according to Bloomberg. Barclays engaged in deceptive practices, fraud and mislead investors as it looked to obscure how much high-frequency traders were buying and selling, the suit will allege.Dark-pool and other off-exchange trading has been estimated to make up almost 40% of stock trading volume Stateside.OH