Investigators are gearing up to target a wave of insider trading cases on Wall Street.
It's reported that after years of investigation, the Securities and Exchange Commission is cracking down on hedge fund managers, lawyers and other finance workers.
On Friday, billionaire investor and Galleon hedge fund founder Raj Rajaratnam was charged, with five others, with $US25 million worth of insider trading.
It has been described as the biggest hedge fund insider trading case in US history.