Insider Transactions and Performance: The Portuguese Case

Abstract

This study investigates the relevance of stock buy/sell transactions by insiders in Portuguese companies' performance. To achieve this aim, the sample covers the period from 2013 to 2017. The data from buy/sell transactions by insiders were collected in the internal transaction reports delivered by the companies to the Portuguese Securities Market Commission for the same time interval. The results, using panel data methodology, suggest a negative relationship between the long/short positions and the companies' performance, although the volume traded is not significant. Therefore, the increased control of Portuguese companies by their managers signals the existence of conflicts of interest of the managers, whether due to financial reasons or to strengthen their continuity in the position. As far as the authors are aware, this is the first time that a study has been carried out using insider transactions for Portuguese companies and their influence on corporate performance.