Miller (1977) hypothesizes that IPO underpricing arises because the issue price is based on the average opinion while the aftermarket price is set by a minority of optimistic investors. Using a unique data set of institutional bids for a large sample of Chinese IPOs, we show that the IPO issue price is positively related to the quantity-weighted average bid price and unrelated to the market-clearing bid price. In contrast, the first-day closing price is positively related to the market-clearing bid price and unrelated to the average bid price. Overall, our results provide strong support for Miller's explanation of IPO underpricing.

Using a sample of Chinese A-share listed firms from 2007‐2017, we examine the impact of short sales on a firm's financial constraints. We develop three conceptual frameworks, the negative information effect, the undervaluation effect, and the deterrent effect, based on the prevailing theories and conduct an in-depth empirical analysis using the difference-in-differences, propensity score matching, and instrumental variable methods. Our findings suggest that: (1) Short sales generally worsen a firm's financial constraints by reducing its ability of raising cheap and overvalued external capital. (2) A shortable firm's financial constraints deteriorate more seriously in the case of higher credit risk or information asymmetry. (3) When a firm becomes shortable, its negative media coverage increases, external financing cost rises, and the amount of new external financing decreases. (4) The adverse impact of short sales on financial constraints is more pronounced for inefficient state-owned firms and mainly concentrates in the short term. Collectively, these results support the underlying logic of the negative information effect. However, further analysis shows that: (1) The deterrent effect also exists but is much weaker than the negative information effect. (2) The strength of the two effects will “wan and wax” with time or circumstances. Thus, the deterrent effect may outweigh the negative information effect by easing a firm's financial constraints in some cases, such as in the long term after short sales deregulation and when short sales magnitude is low or the managers are more sensitive to the decline of stock price. Our paper provides new insights into the impact of shorts sales on financial constraints, revealing some unique Chinese features compared to the US market and offering valuable lessons to other emerging markets.