market concentration

In economics, market concentration is a function of the number of firms and their respective shares of the total production in a market. Market concentration is the portion of a given market's market share that is held by a small number of businesses. To ascertain whether an industry is competitive or not, it is employed in antitrust law land economic regulation. When market concentration is high, it indicates that a few firms dominate the market and oligopoly or monopolistic competition is like