The Financial Industry Regulatory Authority has charged brokerage firm Wedbush Securities with failing to adequately supervise its customers as it gave them access to the stock market, allowing thousands of traders to carry out manipulative trades, Reuters reports.

This is the second time this year that a U.S. regulator has filed civil charges against the Los Angeles-based firm. In June the Securities and Exchange Commission charged the company and two of its officials with failing to maintain adequate risk controls in providing customers access to the market. The agency asserted that Wedbush allowed customers to send orders to markets via platforms that it did not directly and exclusively control.