Federal regulators on Monday charged the co-founder of a New York hedge fund and three other individuals with insider trading, the latest action in what the government has called the biggest insider-trading case in U.S. history.

The Securities and Exchange Commission announced it filed a civil lawsuit against hedge fund Trivium Capital Management, its co-founder Robert Feinblatt and analyst Jeffrey Yokuty. The SEC also filed charges against Sunil Bhalla, a former senior executive of tech company Polycom, and Shammara Hussain, a former employee at a consulting firm that did work for Google. The agency said Bhalla and Hussain provided confidential information that enabled Feinblatt and Yokuty to make about $15 million from trading on the information.

So far the SEC has filed civil charges against 27 people and hedge funds in a wide-ranging probe of the Galleon group of hedge funds and its founder. The government says Galleon funds made about $69 million in illegal profits. Raj Rajaratnam, the one-time billionaire founder of the Galleon funds, has pleaded not guilty. Federal authorities have arrested 23 people on criminal charges in the case; 14 have pleaded guilty.

The SEC alleged in its suit that Feinblatt and Yokuty traded using confidential information they received from Roomy Khan, a Florida investor who pleaded guilty in 2009 to conspiracy and securities fraud in the Galleon case. Khan has been cooperating in the government's investigation.

The SEC said that Bhalla gave Khan inside information on Polycom's fourth-quarter earnings in 2005, and that Khan traded on the information and gave it to others, including Feinblatt and Yokuty. The SEC also alleged that Hussain gave Khan confidential information about Google's second-quarter earnings in 2007.