MCI Communications Corporation used to be an American telecommunications company known for playing a vital role in the legal and regulatory changes that led to the breakup of AT&T’s monopoly over American telephony. Originally created to be a company building microwave relay stations, it became the second-largest long-distance provider in the United States.

It was on this day, September 14, 1998, that MCI Communications and WorldCom completed a $37 billion merger and became MCI WorldCom. A little over a year later, Sprint Corporation and MCI WorldCom announced a $129 billion merger agreement, but it was not completed because of the U.S. Department of Justice and European Union were worried about it creating a monopoly.

Since the MCI WorldCom merger, the company faced many financial scandals and also a bankruptcy, both leading to it changing its name to MCI in 2003. In 2006, Verizon bought the company, and the MCI trademark has become a sub-page of Verizon.com.