AN EMPIRICAL ANALYSIS OF FIRM PERFORMANCE UNDER ISO 9000 CERTIFICATION

This study investigates the effect of the ISO 9000 certification on the performance of firms listed on the Athens Stock Exchange. The ISO 9000 certified firms are classified into two groups: the group of firms that hold the certification for all the years that are listed (always) and the group of firms that initiate the certification at some point after entering the stock market (starters). The effect of the ISO 9000 certification on firm performance is estimated by comparing the financial performance of both certified groups to the financial performance of a control group of non-certified firms using a difference-in-differences econometric approach. The ISO 9000 certification effect is further examined by comparing the financial performance between the two certified subgroups (always vs starters). The empirical findings indicate that the ISO 9000 certified firms significantly outperform the non-certified firms. Furthermore, the findings reveal that firms initiating the ISO 9000 certification after entering the stock market (starters) are more benefited from the certification in comparison to firms that are certified for all the years that are listed (always).