Federal prosecutors said David Kugel, a former supervisory trader at Madoff's investment firm, is cooperating with authorities and would to plead guilty in Manhattan federal court on Monday, the New York Post reported.
In a letter to the judge, prosecutors said Kugel will admit to conspiring in Madoff's record $65 billion fraud "beginning in the early 1970s through December 2008."
Kugel allegedly made more than $8 million working for Madoff and pocketed more than $13 million in phony profits after investing $25,000 with him in 1977, court papers show.
Kugel faces a sentence of up to 85 years in prison.
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