Authorities arrested four people and will announce charges against several more on Wednesday as part of the government's sweeping probe into insider trading at hedge funds, an FBI spokesman said.
The charges are part of the government's long-running investigation into the alleged sharing of confidential information on publicly traded corporations with hedge fund managers and analysts. In the biggest case so far, onetime billionaire and hedge fund tycoon Raj Rajaratnam was convicted of insider trading and is now serving an 11-year prison term.
The defendants include Anthony Chiasson, who co-founded the Level Global Investors hedge fund. He turned himself in to the FBI in New York, an FBI spokesman said.
Todd Newman, who headed technology trading for hedge fund Diamondback Capital Management from Boston, was arrested, the spokesman said.
Newman had been placed on leave of absence in 2010 and subsequently was let go by that firm. Reuters in November reported the government's interest in Newman.
Chiasson and Newman were charged in U.S. District Court in Manhattan with one count of conspiracy to commit securities fraud and other charges, according to court papers.
The FBI also arrested Jon Horvath, who is currently employed at Sigma Capital management, a unit of Steven A. Cohen's $14 billion hedge fund SAC Capital, said a person familiar with the case who is not authorized to speak publicly.
A spokesman for SAC Capital could not immediately be reached for a comment. Lawyers for Chiasson, Newman and Horvath did not immediately respond to requests for a comment or could not immediately be reached.
A fourth person was arrested in Los Angeles earlier on Wednesday.
Charges were expected to be made public against three other individuals at a press conference later on Wednesday.
More than 50 people have been arrested or charged in overlapping federal insider trading probes that were first unveiled in October 2009. Most of these people have pleaded guilty or been convicted.
Many of the cases have been based at least in part on the use of government wiretaps authorized by federal judges.
Four hedge fund firms -- Level Global, Diamondback, Loch Capital Management and Barai Capital Management -- were raided by the FBI in late 2010 as part of the insider-trading probe. Level Global, Loch and Barai have since folded.
Rajaratnam, founder of the Galleon Group, remains the best-known investor implicated in the probe. A jury convicted him of fraud and conspiracy charges last May.
Rajat Gupta, a former chief of the consulting firm McKinsey & Co and director of both Goldman Sachs Group Inc and Procter & Gamble Co, has been charged with providing illegal tips to Rajaratnam. He is fighting those charges.