Postprint version. Published in Finance Letters, Volume 3, Issue 6, January 1, 2005.
Copyright © 2005 Elsevier.
NOTE: At the time of publication, the author Sanjiv Jaggia was not yet affiliated with Cal Poly.
We document significant momentum effects in the high-tech IPO aftermarket beyond the initial (underpricing) run-up. Cumulative market-adjusted returns (CMARs) reveal a striking pattern. A local peak of just over 10 percent is reached around 20 trading days post-IPO coinciding with the expiry of the “quiet period”. A global peak (of about 33 percent) is reached after 105 trading days. The CMAR decays fairly rapidly thereafter possibly in anticipation of the expiry of the six-month lockup period. Further, we find strong evidence of a linkage between technical ex-ante observable variables and the momentum build-up. We conjecture that visceral factors may at least partially underlie the investor behavior that gives rise to the bubble-like CMAR pattern.