Enron was a high-flying energy company that sought to transform itself into the world’s biggest energy trader.
At one time it was by stock market value the seventh largest US company, led by its dynamic, politically connected chairman Kenneth Lay.
But its share price collapsed when it emerged that the company had been concealing losses by setting up shell companies.
Most executives appear to have condoned these practices; but one of them, Sherron Watkins, wrote a now notorious letter to Mr Lay warning him of serious conflicts of interest.
Many executives benefited from the company’s high share price by cashing in their stock options.
But employees who had put all their pension money in Enron shares lost everything when the firm went bankrupt in December.