Abnormal returns from insider trading - does insider trading generate abnormal returns for the Swedish stock exchange and large cap Stockholm?

Sammanfattning: This paper studies insider trading and abnormal returns on the Large Cap list of the Swedish stock exchange using a sample of 119 firms and 10528 individual transactions between the period 2016-2022. The study is built on the theoretical framework of the efficient market hypothesis and information asymmetry. The research questions are answered using an event study combined with a regression model for hypothesis testing. The results imply that insider trading generates abnormal returns. Furthermore, the study finds a difference in the extent of abnormal returns when comparing buy- and sell transactions. However, similar results are not found when comparing insiders of different seniority. When considering individual days, the results indicate that abnormal returns occur the day before, one- and two days after the day of which news of insider transactions are published.