This article highlights one of the actual ISO 9001 issues � a phenomenon of decrease in certification in Slovenia and worldwide as well. Our case study in Slovenia was focused on future functioning and financial performance of organisations having their ISO 9001 certificates cancelled (CCOs). The study was performed as a longitudinal survey covering more than 55% of the Slovenian certification market and taking a four-year period from 2009 to 2012. CCOs were analysed upon a study of the literature and previous research. The results showed that their number and size did not differ significantly from year to year in the analysed period. Furthermore, majority of them showed decreasing financial results after certificate cancellation resulting in 45% of the organisations closing down in those four years. However, the number of cancellations was significantly related to the type of industry. The findings of our study might be important for managers and certification bodies, as they suggest that a cancelled ISO 9001 certificate could be understood as an early external signal indicating possible business problems in the organisation. Of course, we cannot simply generalise our findings only upon this case study; however, these findings can be a signal for further research.