Ebbers, a former milkman, was imprisoned for 25 years in September 2006 over the accounting fraud. He was released early in December 2019 on the grounds of ill-health.
WorldCom had been known as Long Distance Discount Services (LDDS) when he took over, operating in the newly liberated market for long-distance telephony services following the break-up of the AT&T telecoms monopoly. Ebbers led the company on a string of mergers and acquisitions, changed the company's name to LDDS WorldCom in 1995, subsequently becoming just WorldCom.
Ebber fought off much larger rivals Sprint and AT&T to acquire Advanced Telecommunications Corporation for $720 million. This was followed by a string of big-money buys. These included Metromedia Communication in 1993; Resurgens Communications Group, also in 1993; IDB Communications Group in 1994; Williams Technology Group in 1995; MFS Communications in 1996; and, biggest of all, MCI in 1998.
At the time, the MCI deal was one of the biggest mergers in corporate history at $37 billion, fighting off BT in the process. BT had lined up a $20 billion deal before WorldCom swooped, forming MCI WorldCom in the process after its acquisition was completed.
In 1999, Ebbers had a crack at a $129 billion merger of MCI WorldCom with rival Sprint until opposition from antitrust regulators in both the US and European Union squashed the deal.
In total, WorldCom had been built on the back of some 60 acquisitions. But all of that deal-making had left the company exposed to the dot-com crash of 2000 and the economic recession of 2000-2002.
From around 1999, Ebbers, his CFO Scott Sullivan and a number of other senior WorldCom executives had adopted a number of fraudulent accounting methods to falsely inflate the company's earnings. This enabled the company to report pre-tax profits in 2001, for example, when it ought to have reported a loss.
Ebbers had also used his stock holdings in WorldCom to raise funds for a number of other businesses, and he was exposed to margin calls as WorldCom's share-price collapse gathered pace. Initially, he persuaded the board of the company to provide loans and guarantees of $366 million to cover his margin calls - the board no doubt agreeing as the sale of a substantial amount of stock owned by the CEO would cause the company's stock price to fall further.
However, Ebbers resigned as WorldCom looked like it would be forced into bankruptcy protection.
The accounting fraud was uncovered within months of his departure as the result of an investigation instigated by his successor, former UUNet CEO John Sidgmore. Initially, it was estimated at $4.5 billion, but more in-depth investigations increased the figure to $11 billion.
When the allegations first surfaced, Ebbers told the congregation at his local church that he was completely innocent. "I just want you to know you aren't going to church with a crook", he said. "No one will find me to have knowingly committed fraud."
Ebbers was found guilty on all counts on 15th March 2005 and, after his appeal failed, inmate #56022-054 drove himself to jail on 26 September 2006.
Meanwhile, WorldCom filed for Chapter 11 bankruptcy protection in July 2002, and the post-bankruptcy company, renamed MCI, was acquired by Verizon Communications for $7.6 billion.