Credit Suisse was hit with a $6.5 million fine for doing too little to prevent potential market manipulation by U.S. clients.

The Swiss bank was slammed by U.S. industry officials for and fined $6.5 million for failing to keep an eye on major U.S. institutional clients, Finra, or the Financial Industry Regulatory Authority, said in a statement. Credit Suisse said it is «pleased to have resolved these matters with FINRA and these exchanges,» according to a brokerage industry publication

Specifically, the Zurich-based lender granted clients – brokers and other institutional-sized clients – direct access to exchanges without proper oversight. Credit Suisse won more than $300 million in revenue from trading more than 300 billion securities – a move that sparked more than 50,000 alerts at Finra, which is a U.S. broker self-regulatory body. 

Major Trading Slice

Three Credit Suisse clients in the U.S. made for the bulk of the alerts, which are meant to flag potential manipulation of markets like spoofing, layering, «wash» sales and pre-arranged trades. The trio, which wasn't named, made for roughly one-fifth of the Swiss company's overall order flow at their peak, Finra said.

Credit Suisse is mulling returning to the U.S. market for the wealthy, finews.com reported in October. The bank sold its brokerage arm in the Americas to Wells-Fargo more than three years ago as part of a wide-ranging restructuring under CEO Tidjane Thiam.