Estudo de ofertas públicas de ações no Brasil e "underpricing" no período de 2003 a 2009

Abstract

The capital market in Brazil has experienced, especially from the year 2003 to 2009,several changes and significant growth due to the global economic and financial environment as well as internal factors highlighting the regulatory improvements, development and credibility. As a result of this growth, we have observed a large number of companies that became public especially from 2006 on. The stock price behavior during this period has showed significant short-term positive returns, even when compared to Ibovespa index rates (Sao Paulo s Stock Exchange).Some potential explanations for such events may be the stock issue below the correct price (underpricing), informational asymmetry, the winner's curse (Rock ,1986) or other market anomalies discussed in the financial theory. This research focused the study in two possible factors: (1) issue below the correct price, known in financial literature for underpricing, and (2) the risk and return function as explanatory for stock returns in IPO issued from 1st, 30.th, 60.th, 90.th and 180.th days considering the sample of companies which registered initial public offerings (IPO) from 2003 until December 2009 listed on the Bovespa and the Securities Commission (CVM) and which had daily close available prices. The objective for this study was to verify the existence of underpricing in the IPO process and whether the observed abnormal returns can be explained by the risk and return function. As for the conclusion, in line with results of other recent researches for Brazilian stock market, were observed positive returns in the short term and negative returns for long term concluding that underpricing is a practice adopted in IPO s in Brazil as well as in other developed capital markets.