Stamford, Conn.-based CR Intrinsic Investors is an affiliate of SAC Capital Advisors, a firm owned by Steven A. Cohen. Cohen's net worth is estimated at $8.8 billion on the Forbes 400 list of the richest people in the U.S.
Court papers in Martoma's case repeatedly allude, without using Cohen's name, to his dealings with Martoma in the lead-up to an announcement about the drug trial.
The FBI subpoenaed SAC and other influential hedge funds in November 2010. Martoma is the fourth person associated with SAC Capital to be arrested on insider trading charges in the last four years.
Cohen has not been charged with any crime. SAC spokesman Jonathan Gasthalter has said the company and Cohen are cooperating with the inquiry and "are confident that they have acted appropriately."