Today, New York State Attorney General Eric Schneiderman spoke out against anti-competitive practices by high-speed trading firms, which he said use co-location to gain early access to vital market-moving data. According to a report in The Wall Street Journal, Schneiderman described co-location and other practices as "valuable advantages [that] give high-frequency traders a leg up on the rest of the market." Previous reports indicate the Attorney General's office is actively probing stock exchanges for more information regarding the practice, although it's unclear if the investigation will result in any charges.

In the past, high-speed trading firms have been accused of using fast transmission times as a cover for selling early access, as when a Fed announcement in September seemed to affect markets simultaneously in Chicago and Washington DC. One High-speed trading firm called Virtu recently revealed that, in two years of trading, they made money from the market on every day but one, an advantage they ascribed to market-making arbitrage tactics. The firm plans to go public later this year.