Competitive effect of IPO's in Tehran Security Exchange: an event study analysis

IPOs acknowledged as an important and continuous event in stock markets. A lot of research investigated why do company go public? How to price a new company? And the abnormal return of IPOs in the short and long term. In another aspect, we can consider IPOs as an economic event or even critical news and examine its effects on the existing companies' return. In this paper, we attempted to investigate investors' behavior around an IPO and the competitive effect of IPO's in the Tehran Security Exchange using event study methodology. For this purpose, we classified 235 IPO for 14 years based on their size, industry, P/E, and B/M. The results indicate that investors consider the big size and low P/E IPOs as a negative event on the existing portfolio. We also find that the initial filing of an IPO has a negative price impact on existing firms in the same industry.