New York bank regulator Benjamin Lawsky said his investigation into currency trading could go on for months, even after settlements with the U.S. Justice Department. Lawsky spoke at a conference in New York today.

Lawsky, the Justice Department and the Securities and Exchange Commission are investigating whether banks' electronic-trading platforms allow them to take a "last look" at currency orders that allow them to back out of unfavorable trades.

Interest in the last-look practice from enforcers has grown out of a broader investigation into the manipulation of benchmarks and client orders in the $5.3 trillion-a-day currency market.

Lawsky, the head of New York's Department of Financial Services, sent subpoenas to Goldman Sachs Group Inc., BNP Paribas SA, Credit Suisse Group AG and Societe Generale SA in late December as part of his review of currency trading at banks, one of the people said. The information demands don't necessarily indicate the four banks did something wrong, said the person, who asked not to be identified because the matter is confidential.

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