As a very general rule (and there are exceptions): Companies with gross profit margins of 40% or better tend to be companies with some sort of durable competitive advantage. Companies with gross profit margins below 40% tend to be companies in highly competitive industries, where competition is hurting overall profit margins (there are exceptions here, too). Any gross profit margin of 20% and below is usually a good indicator of a fiercely competitive industry, where no one company can create a sustainable competitive advantage over the competition.
