Yield spreads, agency costs and the corporate bond call feature

This paper theoretically compares yields and optimal default policies for callable and non-callable corporate debt. It shows that, contrary to the conventional wisdom, it is possible for the yield spread (callable minus non-callable) to be negative. It also identifies the key determinants of the yield spread. Next, it shows that the optimal default trigger for non-callable debt is higher than the trigger for callable debt, resulting in additional default-related costs. Thus, the use of non-callable debt gives rise to an indirect agency cost of early default, which is the difference in total firm value with callable and non-callable debt. This agency cost provides a rationale for the existence of callable debt. By examining the determinants of the magnitude of this agency cost, the conditions that make callable debt more attractive (to the issuing firm) relative to non-callable debt are identified. This allows certain predictions to be made regarding the likelihood of a call feature in a corporate bond. The model's implications are supported by existing empirical studies.