We document discretionary underpricing and partial adjustment of IPO prices in the public offer tranche of Japan's hybrid auction regime, in which investor information differences are not important, there are no roadshows, preferential allocations are negligible, institutional investing is low, and the public offer tranche cannot fail. The magnitude and variation of underpricing in our sample, which spans relatively hot and cold markets, are similar to those reported for US IPOs. The evidence is most consistent with underpricing arising from an implicit contract to allocate risk related to initial mispricing where, in exchange for guaranteeing a minimum price, the underwriter participates indirectly in upside performance. The results raise important questions about interpretations of IPO underpricing in the US.

We study the role of banking relationships in IPO underwriting. When a firm in Japan goes public, it can engage an investment bank that is related through a common main bank, or can select an alternative investment bank. The main bank relationship can be an efficient way for the investment bank to acquire information generated by the main bank, but may give rise to conflicts of interest. We find that main bank relationships give small issuers increased access to equity capital markets, but that issuers of large IPOs often switch to non-related investment banks that are capable of managing large offerings. While investment banks seek to exploit bargaining power with related issuers, issuers respond to expected high issue cost by switching to non-related investment banks. The net result is that total issue costs through related and non-related investment banks are similar. With respect to aftermarket performance and use of proceeds, we find no evidence of conflict of interest or self-dealing for either the main bank or the investment bank.