Klausner et al. survey the evidence. Conventional (non-SPAC) IPOs with 20+% price declines attract modestly more lawsuits than equivalently sized already-public companies with 20+% stock price drops attract 10b-5 lawsuits (18% vs. 13%).

The resulting IPO lawsuits are also dismissed less frequently, although at a higher rate than the strict liability scienter standard in Section 11 might lead one to guess (47% for IPOs, 58% for already-public companies).