Testing stock market efficiency from spillover effect of Panama leaks

On 3 April 2016, Mossack Fonseca provided the historically most significant leak of its shareholder’s data for owning offshore companies. Shareholders include many political and influential figures around the globe, which causes a moral hazard. The study analyses the effects of Panama leak events on five stock exchanges to ensure the market efficiency and investor perception related to the Panama leaks. Event study methodology is used on five occasions associated with Panama papers, i.e., the resignation of the Prime Minister of Iceland on 5 April 2016, Jurgen Mossack’s resignation on 7 April 2016, the resignation of the Spanish Minister of Industry on 15 April 2016, the 450 personalities of Pakistan that were nominated in Panama papers on 15 April 2016, and the formation of an inquiry commission to inquire into the matter. The market efficiency of five stock exchanges was checked, i.e., the KSE 100 of Pakistan, the OMXIPI exchange of Iceland, the IBEX 35 of Spain, the New York stock exchange (NYSE), and S&P 500. The market remains efficient for most events and investor behaviour changes for one or two days around the event day (this event has concise term significant abnormal returns in all stock exchanges or concise term significant abnormal macroeconomic effects are observed in all stock exchanges).