The unidentified co-conspirator who funneled tips and cash between a lawyer and trader accused of running a 17-year scheme to trade on corporate merger secrets was a former colleague of both defendants, the New York Times reported.

It identified the co-conspirator, who was not charged in one of the largest U.S. insider trading cases on record, as Kenneth T. Robinson, a former trader and mortgage broker on Long Island.

Robinson could not be reached for comment.

Federal prosecutors this week accused Matthew H. Kluger and Garrett D. Bauer of reaping more than $32.2 million from trades on tips about upcoming mergers and acquisitions that Kluger learned as a lawyer at Wilson Sonsini Goodrich & Rosati PC, the pre-eminent firm representing Silicon Valley technology companies.

The New York Times report on Friday said the scheme unraveled after Robinson made $200,0000 from buying shares of 3Com Corporation, which was soon to be acquired by Hewlett-Packard. The profit alerted the SEC to Robinson, the report said, citing a person with knowledge of the investigation who spoke anonymously because its details are not public.

Robinson began taping conversations with Kluger and Bauer after federal authorities raided his house in early March, according to the New York Times.

The insider trading complaint relies on many recorded telephone calls. In one call, on March 28, Bauer was said to have discussed how to dispose of $175,000 of cash with his fingerprints that he had given the co-conspirator.

More than $109 million was invested in the purported scheme, prosecutors said. Kluger is a resident of Oakton, Virginia, while Bauer lives in New York.

(Reporting by Mark Weinraub; editing by Chris Wilson)

Insider trading