The National Center for the Middle Market at the Ohio State University Fisher College of Business[7] as well as Dun & Bradstreet’s proprietary database of commercially-active U.S. firms[8] define middle market businesses as those companies with revenues between $10 million and $1 billion per year.
The definition is defined in reference to small businesses, which earn less than $10 million in annual revenue, and big business, which earn at least $1 billion in revenues and are generally the smallest eligible for a credit rating by one of the "major" credit-rating agencies.
According to an in depth report by ESSEC Business School and GE Capital, across the UK, Germany, France and Italy (the EU-4), the mid-market represents a relatively small number of companies (ranging from a low of 1.2% in Germany to 1.7% in France) and yet it generates about one third of private sector revenue and employs about a third of each country's workforce.
In the study, Professor Ashwin Malshe of ESSEC defined the middle market differently for each country.
Entities have evolved to serve businesses in the middle market, including for-profit and institutions of higher learning.