Prior literature documents that larger boards pursue conservative investment policies and that their decision outcomes are moderate, which promote an environment of risk aversion. I argue that this risk aversion hurts equity holders when firms hold a larger amount of long-term debt. Addressing potential endogeneity problems associated with board size, I find an equity discount associated with larger boards in firms that have greater amounts of long-term debt. On the other hand, larger boards are associated with an equity premium when firms have a greater short-term debt-to-assets ratio. The equity discount associated with larger boards disappears in firms with no long-term debt. Further analysis also indicates that firms with larger boards enjoy a better credit rating and a lower realized cost of debt. Overall, analysis in this study suggests that the association between board size and equity value is a function of a firm's debt structure.
