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A telecommunications company that was at one time the second largest long distance provider in the United States. It had a large role in the expansion of Internet use in the 1990s. It is known for its notorious bankruptcy in 2002 following massive accounting fraud that resulted in several executives receiving jail sentences and investors losing billions of dollars. WorldCom is often associated with the Enron scandal because they occurred at about the same time and because both WorldCom and Enron used the accounting firm Arthur Andersen. It is now called MCI and is a subsidiary of Verizon.