The NASD, the US securities regulator, fined a Citigroup broker $400,000 (€318,000) and suspended him for 90 days for making improper short sales in his personal accounts.

According to NASD, Steven Norin, a broker with Citigroup Global Markets, will have to disgorge the profits he earned from the profitable improper short sales and to pay a fine of over $100,000.