Those talks had been a closely guarded secret, but Thursday the Justice Department quietly issued a notice to victims required under federal law:
"The Department of Justice is considering entering into a sentencing agreement with the defendant in this matter," the notice reads. "Such a sentencing agreement could restrict the parties and the Court from recommending, arguing for, or imposing certain sentences or conditions of confinement. It could also restrict the parties from challenging certain issues on appeal, including the sentence ultimately imposed by the Court at a future sentencing hearing."
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A Justice Department official hinted that a deal could include a monetary component as well, telling CNBC in an e-mail: "The Department's goal is, and has always been, to ensure that Mr. Skilling be appropriately punished for his crimes, and that victims finally receive the restitution they deserve."
Skilling's longtime defense attorney Daniel Petrocelli declined to comment.
Lake, who imposed the original sentence, would have the final say in the sentence. The posting of the notice, however, suggests the parties have some indication he will go along. Lake held a private conference call with attorneys for both sides last month.
For Skilling, who has consistently maintained his innocence, an agreement would end a long ordeal, although his conviction on 19 criminal counts would likely stand. The government, meanwhile, would avoid a potentially messy court battle over alleged misconduct by the Justice Department's elite Enron Task Force appointed in the wake of the company's sudden failure in 2001.
Skilling's attorneys had planned to move for a new trial based on that alleged misconduct. Under a sentencing agreement, that motion would likely be dropped.
Skilling, who developed Enron's business model as an "asset-light" energy trading company, rose to CEO in early 2001, only to resign six months later. Soon after that, Enron began its sudden plunge into what was at the time the largest bankruptcy in U.S. history.
—By CNBC's Scott Cohn