[JURIST] Investment research firm executive Tai Nguyen pleaded guilty [press release] to insider trading charges in connection with the investigation into Raj Rajaratnam‘s [JURIST news archive] Galleon fund. Nguyen, an executive of the research firm Insight Research LLC, surrendered to the FBI [Reuters report] Tuesday morning in compliance with the authorities’ investigation of Galleon. Rajaratnam was convicted of 14 counts of insider trading [JURIST report] in May 2011 in the largest hedge fund insider trading case in US history.

Earlier this month, former Goldman Sachs [corporate website] director Rajat Gupta was convicted [JURIST report] of three counts of securities fraud and one count of conspiracy to commit securities fraud, also in connection with Rajaratnam. Several other defendants have pleaded guilty in connection with the case. Former hedge fund consultant Danielle Chiesi pleaded guilty [JURIST report] in January. Former IBM senior vice president Robert Moffat was sentenced to six months in prison in September and ordered him to pay a $50,000 fine for his role in the scheme after pleading guilty [JURIST reports] in March 2010. Former Intel Capital executive Rajiv Goel pleaded guilty [JURIST report] to insider trading charges in February 2010. Rajaratnam, Chiesi, Goel and Moffat were arrested in October 2009 and charged [complaint, PDF] along with two other individuals and two business entities with insider trading. The complaint alleged that the individuals provided Galleon Group and another hedge fund with material nonpublic information about several corporations upon which the funds traded, generating $25 million in illicit gain. Rajaratnam and Chiesi originally pleaded not guilty [JURIST report] in December 2009 after being indicted for insider trading.