Former WorldCom Inc. chief executive Bernard J. Ebbers was found guilty Tuesday on all counts against him of conspiracy, securities fraud and false regulatory filings for his role in a massive accounting fraud that led to the downfall of the nation's second-largest telecommunications firm and cost investors billions of dollars.

Ebbers sat impassively with his fingers laced as the jury forewoman delivered a guilty verdict on all nine counts. He stared intently at each juror as the judge polled them individually.

The jury of seven women and five men held Ebbers, 63, responsible for filings that boosted WorldCom's reported earnings and hid the fact that its business was deteriorating for nearly two years. WorldCom filed for bankruptcy protection in July 2002, later announcing it had uncovered $11 billion in fraudulent accounting entries.

The firm's collapse, combined with the implosion of Enron Corp., sounded the death knell for the 1990s stock market boom and prompted Congress to enact strict new laws holding corporate chieftains more accountable for their companies' financial reporting.

"It's a very sad day for Bernie Ebbers, but it's a very good day for Wall Street and investors," said St. John's University law professor Anthony M. Sabino. "If you're the chief executive, you're the captain of the ship. You can't get in front of a jury and say, 'I'm not responsible.' "

That could be a chilling thought for former chief executives whose trials are underway or pending, including HealthSouth Corp. founder Richard M. Scrushy and former Enron executives Kenneth L. Lay and Jeffrey K. Skilling, who are all using similar defenses.