Bernie Ebbers, the former Worldcom boss found guilty of fraud and conspiracy in connection with the firm's bankruptcy, has called for a new trial.
Bernie Ebbers is hoping a new trial will bring a happier verdict
Mr Ebbers, 63, was also found guilty of seven counts of filing false documents.
His team claims the judge should have given immunity to three executives who could have cleared him - in the end, the Worldcom employees did not testify.
Mr Ebbers contests that the jury had too much leeway in what to consider, making his conviction more likely.
About 20,000 workers lost their jobs and shareholders lost close to $180bn (£95bn) when Worldcom collapsed in 2002 with an $11bn hole in its accounts.
Mr Ebbers has always contended that the fraud was the work of his former finance chief Scott Sullivan and he knew too little about what was going on to be culpable.
Biggest US bankruptcy
Founded in 1983, Worldcom was the second biggest long distance phone firm in the US with 20 million customers.
It ran into numerous difficulties during the technology boom and got into debts of $41bn.
The accounting irregularities were revealed in June 2002.
Worldcom originally put a value of $4bn on the financial black hole. That has been slowly rising, first to $7bn, then $9bn and is now thought to total $11bn.
Total losses to shareholders since Worldcom's collapse are $180bn.
Mr Sullivan, who pleaded guilty to the charges levelled against him, claimed his actions were directed by his boss.
Mr Ebbers is set to be sentenced on 13 June and could spend the rest of his life behind bars. He is facing as many as 85 years in prison.
In papers filed on Monday, lawyers for Mr Ebbers said that the problems in the court case "seriously compromised the fairness of the trial".
Without the promise of immunity from prosecution, the three former Worldcom executives would have invoked their right not to incriminate themselves had they been called to the witness stand, lawyers said.
Mr Ebbers contends that jurors should not have been allowed to convict him on consciously avoiding the fraud, only on whether or not he knew about it.
He also complains that the prosecution should have had to prove that Worldcom's accounting practices did not comply with generally accepted practices.
The verdict was the biggest success for US prosecutors as they sought to crack down on corporate wrongdoing.
Worldcom has since emerged from bankruptcy and is now known as MCI.