Schapiro Reportedly to Head NASD Arm: Mary Schapiro has agreed to leave the top post at the Commodity Futures Trading Commission to head the new regulatory arm of the National Assn. of Securities Dealers, a source said. A formal announcement is expected later this week. Schapiro's new job will be to oversee the new NASD Regulation Inc., which will supervise the conduct of more than 500,000 securities brokers and more than 5,000 firms nationwide. The NASD agreed to split its regulatory duties and the Nasdaq stock market into separate divisions based on a recommendation by a special commission.