Product–market flexibility and capital structure

• A new determinant of capital structure, product–market flexibility, is examined.
• Product–market flexibility arises from firm's ability to adjust price and/or quantity.
• Product–market flexibility can have a significant effect on optimal debt level.

Many companies have the ability to adjust their product's price and/or quantity in response to changes in the marketplace. We show that this product–market flexibility or market power, hitherto ignored in the contingent-claim modeling literature, can potentially have a significant effect on the corporate capital structure decision. When the firm is operating at full capacity, product–market flexibility is not important, hence market power has a negligible effect on optimal capital structure. However, when operating below capacity, product–market flexibility becomes important and market power has, in general, a positive effect on optimal debt level and optimal leverage ratio. This is consistent with available empirical evidence. Numerical results indicate that the effect of product–market flexibility on optimal debt level and optimal leverage ratio can potentially be large enough to be economically significant, hence it should not be ignored as a determinant of capital structure.