A jury had found Bernie Ebbers, the former head of WorldCom, guilty of the biggest accounting fraud in history over his role in the firm's $11bn collapse.
After deliberating for eight days, the New York jury found Ebbers guilty on nine counts, one each of conspiracy and securities fraud and seven of false regulatory filings. He faces a possible 85 years in jail when sentenced on 13 June.
Ebbers had claimed that he knew nothing of the fraud going on in his company and had little knowledge of financial matters, something Assistant US Attorney William F Johnson called the "aw shucks" defence.
Ebbers seldom used email and it was down to the jury to believe him or WorldCom's former chief financial officer, Scott Sullivan, who has already pleaded guilty.
The court heard that WorldCom fixed its corporate figures to the tune of $11bn over 2000 to 2002 in order to keep the share price high. When the company collapsed, investors lost $180bn and 20,000 people were laid off.
The decision is bad news for Enron chief executives Jeff Skilling and Kenneth Lay, who are both thought to be relying on similar defence strategies when their trials come to court later in the year. Former Enron chief Andrew Fastow pleaded guilty to fraud last year and has been sentenced to 10 years in prison.
Other companies are also having to defend their actions during the internet bubble years and subsequent slump.
Yesterday the Securities and Exchange Commission (SEC) filed charges against Joseph Nacchio, former chief executive of Qwest Communications, and eight other former Qwest officers and employees with fraud.
"The disclosure fraud at Qwest was orchestrated at the highest level of the company to deceive investors," said Randall Fons, regional director of the SEC's Central Regional Office in Denver.
"Qwest's chief executive and other top executives projected revenue and earnings that they knew were overly aggressive, and then all of the defendants used smoke and mirrors to meet those unrealistic projections.
"These individuals must now answer for their conduct and the enormous decline in shareholder value that they caused."
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