Disgraced financier Bernard Madoff will not appeal his 150-year sentence for a fraud that unraveled overnight last December when Madoff confessed to his sons that nearly $65 billion he promised investors was safe was actually only worth a few hundred million dollars.

"We won't be appealing the sentence," Madoff's lawyer, Ira Sorkin, said Thursday. He declined to say why the decision was made. Rebekah Carmichael, a prosecutor's spokeswoman, declined to comment.

The 71-year-old Madoff was sentenced last week after admitting he bilked thousands of investors out of billions of dollars — an epic scheme that spanned the globe, according to a report released Thursday by a court-appointed trustee.

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The report by trustee Irving Picard — responsible for identifying Madoff assets that could be used to compensate victims — said the search "has unearthed a labyrinth of interrelated international funds, institutions and entities of almost unparalleled complexity and breadth."

The report said the trustee has located assets and businesses "of interest" in 11 places: Great Britain, Ireland, France, Luxembourg, Switzerland, Spain, Gibraltar, Bermuda, the British Virgin Islands, the Cayman Islands, the Bahamas. It also said he has sent more than 230 subpoenas seeking overseas records.

More than 15,400 claims against Madoff were filed by a July 2 deadline, the trustee said. He noted there were multiple claims from several accounts.

At his sentencing, Madoff apologized to the victims, describing his fraud as a "problem," "an error of judgment" and "a tragic mistake."

He said he and his wife Ruth were tormented, saying she "cries herself to sleep every night, knowing all the pain and suffering I have caused."

Last Friday, Ruth Madoff was forced out of the $7 million Manhattan penthouse where the couple primarily lived, although they also had homes in the Hamptons, Florida and France. Those homes and several yachts, together worth tens of millions of dollars, are being sold to reimburse investors.

Despite the efforts to liquidate his estate, it was expected that investors will receive only a small portion of the more than $13 billion they originally invested.

Anthony Sabino, a defense lawyer specializing in white collar criminal defense, said the decision against appealing the sentence was no surprise.

"This is his acknowledgment that he really has no chance," he said.

Sabino said that by not appealing, Madoff is showing he "is now going to keep his mouth shut, take his punishment, and he's willing to die in prison. To some extent, he acknowledges that this is the price he has to pay in order to protect others. Who are the others? We don't know."

The size of Madoff's fraud, Sabino said, has brought fresh meaning to "Ponzi scheme," named after Charles Ponzi, who was convicted of mail fraud and bilking thousands of people out of $10 million in 1919-20.

"Charles Ponzi is now a footnote. They're now Madoff schemes," he said.