They never learn. New York's attorney general has filed a fraud lawsuit against Barclays alleging it falsified documents and misrepresented benefits to clients, including pension funds. The suit refers to the bank’s “dark-pool trading,” which allows clients to make large trades while the prices stay private. Prosecutors allege the bank told investors the pool did not have aggressive traders when it did. Even more potentially damaging, the bank is alleged to have told ordinary investors that it would use a stock exchange that “would best execute their trades” but instead mostly put the trade into the bank’s own “dark pool” to cash in. “The facts alleged in our complaint show that Barclays demonstrated a disturbing disregard for its investors in a systematic pattern of fraud and deceit,” said New York Attorney General Eric Schneiderman.