Ultramarginal cost in da Empoli’s work

Highlights the theory of competition advanced by da Empoli in the late 1920s. The main point is the existence of discontinuities in industrial concerns. This leads to the possibility that prices exceed marginal costs and depend also on ultramarginal costs, a new concept elaborated by da Empoli. They are costs that are incurred when the firm is producing beyond the marginal production. Also reviews the various implications of this approach. Stresses the innovative character of his approach and evaluates this in relation to contemporary and successive literature.