Enron's former head of investor relations has become the latest ex-executive of the firm to plead guilty to fraud linked to its collapse.
Enron's fall shocked America
Mark Koenig pleaded guilty in a Houston federal court on Wednesday to securities fraud, and pledged to pay a penalty of $1.49m (£828,000).
Mr Koenig, who faces up to 10 years in jail, has joined Enron officials lining up to testify against their ex-boss.
Enron's one-time chairman Ken Lay is due to face trial on 11 fraud charges.
Mr Lay pleaded not guilty to all the charges when he was arrested in July 2004. His trial is expected to open in the autumn.
Two other top-ranking Enron officials face charges alongside him: Jeffery Skilling, the disgraced energy trading firm's former president, and chief accounting officer Richard Causey.
Other senior Enron officers, including Andrew Fastow who headed its North American business, and the ex-boss of the telecoms unit, Ken Rice, have reached agreements with federal prosecutors to testify for the prosecution.
Mr Koenig admitted misleading investors. In a statement, he said presentations to the public from early 2001 onwards "intentionally concealed the true state of Enron".
He said that he misled Wall Street financial analysts during three conference calls between January and July 2001.
Enron's collapse into bankruptcy in the wake of a false accounting scandal stunned corporate America, and uncovered a wave of similar auditing scandals in its wake.
In July, Enron received court approval to emerge from bankruptcy.