The popular argument for convertibles holds that they provide issuers with “cheap” debt and allow them to sell equity at a premium over current value. Objecting to the “free lunch” implied by such an argument, financial economists have offered other explanations that show how the combination of debt and equity built into convertibles can serve to reduce information and agency costs faced by companies and their investors.

In this article, the authors use the results of their recent study to reconcile the two positions. Following Jeremy Stein's view of convertibles as “backdoor equity,” the authors argue that convertible bond financing is an attractive alternative for companies that have large growth potential but find both conventional debt and equity financing very costly. Such companies are often deterred from funding their capital investments with straight public bonds by their high risk, relatively short track records, and high expected costs of financial distress. At the same time, the information “asymmetry” between management and outside investors can make equity very expensive in such cases. In layman's terms, management may feel that the company's share price does not accurately reflect its growth prospects, or be concerned that the mere announcement of a new equity offering will cause the share price to fall sharply.

To the extent the stock market is persuaded that management's choice of convertibles is based on this combination of promising growth prospects with limited financing options, it is likely to respond more favorably to the announcement of a new convertible offering. The authors furnish evidence in support of this argument by reporting that the market reacts less negatively to those convertible issuers with higher post-issue capital expenditures and higher market-to-book ratios, but with lower credit ratings and higher (post-offering) debt-equity ratios.