The reaction of the Portuguese stock market to ISO 9000 certification

In recent years, the ISO 9000 standard has experienced an extraordinary success. The number of certifications is still increasing worldwide and it is expected that this trend will last. In fact, ISO 9000 certification has become an important factor for doing business in the global market. However, there are many contradictory opinions regarding the real benefits of ISO registration. This paper contributes to this debate by empirically investigating the impact on the Portuguese stock market of achieving ISO 9000 certification. The analysis is based on the event study methodology. The findings suggest that the market positively anticipates the event. A favourable effect is also detected in achieving an early registration within the relevant sector or industry. A financial performance analysis covering a 5-year period centred on the year of the ISO 9000 certification was also carried out. The results suggest that the ISO 9000 certification have a powerful cost effect, decreasing the operating performance and the profitability in the year following the certification. Apparently, companies need one more year to recover those costs.