New limits on trading amid Corzine probe

A federal rule adopted Monday places tighter restrictions on how U.S. trading firms can invest their customers' money. The action comes amid a federal investigation into whether MF Global illegally tapped its clients' accounts before filing for bankruptcy.

The Commodity Futures Trading Commission voted Monday to finalize the rule. It prohibits firms from using money from customer accounts for certain investments, including purchases of foreign debt. It also limits how much of their money can be invested in others, such as money-market mutual funds.

The agency had proposed the rule a year ago but held off adopting it after Jon Corzine, who led MF Global until last month, and others lobbied against it.

Corzine, a former Democratic senator, New Jersey governor and chief executive of Goldman Sachs, resigned as chairman and CEO of MF Global on Nov. 4. The CFTC and other regulators are investigating whether MF Global used client funds for its own needs as its financial condition worsened.