Underpricing Anomaly in Initial Public Offerings: An Application on Borsa İstanbul Health Sector

The phenomenon of underpricing in initial public offerings has been one of the topics debated in the literature for a long time. Examining underpricing, which is an example of price anomalies, and analyzing its determinant factors are vitally important for the establishment of efficient capital markets. The aim of this study is to contribute to the existing literature on the underpricing anomaly observed in initial public offerings. For this purpose, the initial public offerings of companies in the health sub-sector whose stocks are traded in Borsa Istanbul for the period 2006 – 2021 are examined. The short-term price performance of the stocks included in the sample after the initial public offering is analyzed. The main problem for which the answer is sought in the study is whether an investor who buys stocks from the issuance in the initial public offering of the sample companies can get more returns than the market when they hold and sell these stocks for a short period of time. The change in the initial returns of the initial public offerings of health companies, especially as a result of increasing health awareness after Covid-19, is also examined. In the analysis, raw retıurn (RR), abnormal return (AR), cumulative abnormal return (CAR) and compound abnormal returns (BHAR) are calculated during the 1, 3 and 7 days, which are considered as analysis period. If the AR, CAR and BHAR calculated in the analysis are greater than 0 and the their values are statistically significant according to the t-test result, the existence of underpricing can be accepted. According to the results of the analysis, a underpricing anomaly has not been found out in the initial public offerings of the health companies that formed the sample. Based on this finding, it can be expected that investors who bought a stock in an initial public offering would not have an abnormal return if they held it in portfolio basket for 1, 3, and 7 days of the analysis period. It can be recommended that investors not to choose health sector companies while investing in the public offering in terms of obtaining positive higher returns.