New York Attorney General Eric Schneiderman will file a securities lawsuit against Barclays PLC for misrepresenting the safety of its U.S.-based alternative trading system, or dark pool, to investors. Per Reuters:

The lawsuit alleges that Barclays operates its dark pool to favor high-frequency traders and has actively sought to attract them by giving them systematic advantages over others trading in the pool, the source said. 

His office is looking into whether dark pools operate in a way that is consistent with how they market themselves, that they have the interests of investors in mind and that brokers directing trades to their own dark pools do so in a way that does not present conflicts of interest.