Story updated to include SAC Capital information and Janus statement.NEW YORK ( TheStreet) -- Several money management firms, including Steven Cohen's SAC Capital, were contacted by federal authorities Tuesday in a burgeoning probe of insider trading in the money management industry. SAC Capital issued a letter to investors stating that it has received an "extraordinarily broad" government subpoena, according to MarketWatch. A call to SAC's offices was not immediately returned. Janus Capital Group ( JNS) received a request for information, a company spokesperson confirmed. "Janus Capital Group has received an inquiry calling for general information and intends to cooperate fully with that inquiry," a firm spokesperson said in an emailed statement. "Janus maintains rigorous compliance procedures and Janus has confidence in the integrity of its processes and its people." Janus is a publicly traded money management firm with $160.8 billion in assets under management, according to the firm's Web site. Boston-based Wellington Management Co. received a request for "documents" from federal investigators, according to a report by Bloomberg that cited a person familiar with the firm. The article states the request for documents was disclosed on "an internal conference call" but did not explain the firm's role in the probe. A call to a Wellington spokesperson for comment was not returned. According to the firm's Web site, Wellington is an investment adviser with $598 billion in assets under management. The firm is described as a private partnership that has more than 1,800 institutional clients. The insider trading investigation was first reported by The Wall Street Journal Saturday.