Former Enron Chief Executive Jeffrey Skilling has asked a federal judge to overturn his guilty verdict based on an August decision that reversed four other Enron-related convictions.

Skilling, 52, was found guilty in May of fraud, insider trading, conspiracy and lying to auditors for actions leading to his abrupt resignation in August 2001. Four months later, his company — once the nation’s seventh-largest — went bankrupt amid revelations of inflated profits and hidden debts.