a cost of producing that must be borne by a firm which seeks to enter an industry but is not borne by firms already in the industry and that implies a distortion in the allocation of resources from the social point of view
a factor that makes entry unprofitable while permitting established firms to set prices above marginal cost, and to persistently earn monopoly return
A natural or legal constraint that protects a firm from competitors. (p. 310)
a condition that makes it difficult for competitors to enter the market; e.g. patent, trademark, high initial investment requirement.