The determinants of bond call premia: A signalling approach

A signalling model is presented that provides an additional explanation for the determination of call premia on corporate bonds. It is shown that firms may signal their exclusive information about their probability of default by the choice of their call premia. Stockholders of safer firms (i.e., those that have a lower probability of bankruptcy) have a higher incentive for providing a low call premium. This occurs because the call option will be valuable only if the firm survives by the first call date. This event, however, is more likely for the safer firm. The safer firm will therefore be more willing to sacrifice some current revenues (or equivalently, to provide a higher coupon than it would otherwise have to pay in order to sell the bond at par) by determining a lower call premium. The model therefore predicts a negative correlation between safety and call premia, a correlation that has been empirically confirmed by Fischer, Heinkel, and Zechner (1989). This correlation provides support to the signalling theory vis-à-vis the alternative explanation of taxes determining the call premia. Another contribution of this model is that it ties the call premium decision with expectations of future interest rates. Such expectations are considered important by practitioners, but were rarely considered in previous research.