JSE efficiency and share price reaction to forced financial restatements

Abstract

This study uses an event study methodology to empirically examine share price reaction to financial restatement announcements resulting from investigations or recommendations by the GAAP Monitoring Panel and tests, in semi-strong form, the efficiency of the Johannesburg Securities Exchange (JSE). The results indicate that companies making such financial restatement announcements experience significant negative standardised abnormal returns ten days before and five days subsequent to the announcement. As evidenced by the significant negative standardised abnormal returns, it would appear that the announcements convey new information to the market. Although the lack of consecutive negative standardised abnormal returns around the announcement date would suggest that the JSE is efficient in semi-strong form, the five-day time lag between the announcement date and the significant negative standardised abnormal return supports the rejection of semi-strong form efficiency of the JSE.