The SEC has sued former ConvergEx Group executive Khaled Bassily for defrauding for millions through "hidden markups" on customers' securities trades.

A complaint filed on Tuesday in a Manhattan federal court alleges Bassily routinely mislead clients about trading costs, Reuters reports.

Now a director at Cushman & Wakefield, the suit says then-ConvergEx Bassily allegedly coached traders on how to collect hidden charges ("trade profits") without notice, collecting millions in bonuses along the way.

The SEC says the scheme ran from October 2006 until December 2011. In 2013 ConvergEx settled criminal and civil probes into alleged customer overcharges for $150M, with several of its business units admitting to wrongdoing.

A C&W spokesperson says the company's aware of the situation. "We understand the individual has retained personal counsel to represent him," the comment read.

"We are reviewing the issues and, given the seriousness of the charges, are monitoring the situation closely." [Reuters]