We develop a new rationale for initial public offering (IPO) waves based on product market considerations. Two firms, with differing productivity levels, compete in an industry with a significant probability of a positive productivity shock. Going public, though costly, not only allows a firm to raise external capital cheaply, but also enables it to grab market share from its private competitors. We solve for the decision of each firm to go public versus remain private, and the optimal timing of going public. In equilibrium, even firms with sufficient internal capital to fund their new investment may go public, driven by the possibility of their product market competitors going public. IPO waves may arise in equilibrium even in industries which do not experience a productivity shock. Our model predicts that firms going public during an IPO wave will have lower productivity and post-IPO profitability but larger cash holdings than those going public off the wave; it makes similar predictions for firms going public later versus earlier in an IPO wave. We empirically test and find support for these predictions.

We compare the structure and performance of private (non-GSE) mortgage-backed securities sold by large issuers vs. those sold by small issuers over the period 2000–2006. Securities sold by large issuers have less subordination—a greater fraction of the deal receiving AAA rating—than those sold by small issuers. Prices for AAA-rated and non-AAA rated tranches sold by large issuers fell more when the market turned down than those sold by small issuers, and this difference was concentrated among tranches issued between 2004 and 2006. These results suggest that rating agencies grant favorable ratings to large issuers, especially during market booms.