A longtime employee of Bernard L. Madoff Investment Securities LLC has pleaded guilty to falsifying records over the course of decades.

Irwin Lipkin told a court yesterday that he had fudged the books several times over the years, but had no knowledge of the extent of Bernie Madoff’s massive Ponzi scheme. Prosecutors estimate the scheme that grew into a multibillion-dollar fraudulent operation began in the 1970s. Lipkin began working for Madoff in 1964 and was the first member of the firm who was not a relative of Madoff.

“While working for Bernie Madoff, I made accounting entries in financial records that I knew were inaccurate,” Lipkin told U.S. District Judge Laura Taylor Swain yesterday. “At no time before I retired was I ever aware that Mr. Madoff or anyone else at the company was engaged in the Ponzi scheme reported in the media.”

Lipkin signed a plea deal with prosecutors admitting to charges of conspiracy to commit securities fraud and falsifying documents. He faces up to 10 years in prison.

In December 2008, Madoff was arrested for securities fraud after he masterminded one of the largest and longest-running Ponzi schemes in U.S. history. In the end, Madoff cheated his clients out of between $18 billion and $20 billion, according to David Sheehan, chief counsel to Irving Picard, who is liquidating Madoff’s company. Madoff pleaded guilty to the charges in 2009 and is currently serving a 150-year sentence.

Read more about this story on Thomson Reuters.

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