DOW JONES NEWSWIRES 
 

The New York Stock Exchange said Wednesday it has disciplined three firms for trading violations and one person for failing to maintain a fair and orderly market.

The exchange, owned by NYSE Euronext (NYX), said AIM Securities Co., Advanced Securities Co. and Aegis Specialist LLC executed orders for accounts in which they had an interest before executing any sales or purchases for accounts for which they served as an agent.

The companies also were found to have failed to honor published quotes, failed to execute orders in a timely manner and other violations. The infractions occurred between 2002 and 2007.

Meanwhile, it said Michael Marchisi violated exchange rules by freezing the NETS display book, failing to maintain a fair and orderly market under specialist obligations.

The companies consented to censure and a $65,000 joint and several fine. Marchisi agreed to the same sanction. Both the companies and Marchisi consented to the penalties without admitting or denying guilt.

-By Kerry Grace Benn, Dow Jones Newswires; 212-416-2353; kerry.benn@dowjones.com