A former analyst at SAC Capital Advisors, the hedge fund owned by the billionaire investor Steven A. Cohen, has given federal agents the names of about 20 people he said had engaged in insider trading, according to a court filing.
The disclosure of the extraordinary cooperation by the former SAC analyst, Wesley Wang, emerged in a pleading filed by federal prosecutors. In a letter to a judge, the government credited Mr. Wang with substantial assistance in its broad insider trading crackdown.
In addition to the 20 names, the government said information provided by Mr. Wang had contributed to the criminal convictions of more than 10 people.
Hedge Fund Inquiry
The letter, which was filed in connection with Mr. Wang’s sentencing, named 12 individuals who have already been charged or identified in public as part of the investigation. But the section that gave specifics about Mr. Wang’s help — and named other people, according to a person with knowledge of the letter — was heavily redacted.
Prosecutors emphasized that Mr. Wang’s help was still yielding fruit.
“The full extent of Wang’s information and cooperation remains to be fully realized,” the government said in the filing. “Even taking into account what has been developed to date, it is exceptional.”
Prosecutors praised Mr. Wang’s assistance in advance of the sentencing, which is scheduled for Wednesday afternoon in Federal District Court in Manhattan. They urged Judge Jed. S. Rakoff to hand down a lenient sentence. Government cooperators have been vital to prosecutors in the insider trading investigation, which has resulted in the guilty pleas or convictions of more than 70 individuals since mid-2009.
A lawyer for Mr. Wang, Michael Celio, declined to comment.
Mr. Wang is one of a number of former traders and analysts previously associated with SAC Capital, which manages $14 billion and has one of the best investment track records on Wall Street. At least six former SAC employees have been tied to insider trading while at the fund, which is based in Stamford, Conn. The most recent case — an indictment of a former SAC portfolio manager, Mathew Martoma — connects Mr. Cohen to questionable trades.
Mr. Cohen and SAC have not been charged with any wrongdoing, and Mr. Cohen has told his employees and clients that he believes he and the firm acted appropriately at all times. The Securities and Exchange Commission has warned SAC that it may file a civil action against the firm in connection with the Martoma case.
The case against Mr. Wang, a journeyman hedge fund analyst who spent just a couple of years at SAC nearly a decade ago, has largely gone unnoticed.
A native of Taiwan, Mr. Wang, 39, of Berkeley, Calif., worked as a technology stock analyst at the SAC unit Sigma Capital from 2002 to 2005. The F.B.I. first learned about Mr. Wang’s insider trading in 2008 from another cooperator. Agents approached him in early 2009 and he almost immediately began cooperating, agreeing to wear a wire in meetings and also recording telephone conversations with his Wall Street and corporate contacts.
“While these meetings caused Mr. Wang considerable stress, he nonetheless maintained his composure throughout them,” the prosecutors wrote in the sentencing letter.
Last summer, Mr. Wang appeared in a federal court and entered a guilty plea, admitting to leaking confidential information about technology stocks to a former Sigma portfolio manager, Dipak Patel, and to the former head of Whitman Capital, Douglas F. Whitman.
A jury convicted Mr. Whitman in August. He has yet to be sentenced. The government has not charged Mr. Patel.
Mr. Wang testified at Mr. Whitman’s trial. He said that he obtained inside information about Cisco Systems and passed it on to Mr. Whitman, who in turn shared secret data about other companies.
In the sentencing letter, prosecutors said the information provided by Mr. Wang led to their being able to approach certain other people who then also agreed to cooperate. They included Karl Motey, a crucial figure in the government’s extensive investigation into expert network firms — middlemen connecting traders to public company employees — that led to dozens of convictions.
Prosecutors emphasized that they still had plenty of work to do with all of the information supplied to them by Mr. Wang, and requested that his continued cooperation be made a condition of his sentencing.
“Wang has also identified a number of individuals involved in insider trading whom the F.B.I. has not yet approached and/or whom the government has not yet charged,” the letter said.