**6. Conclusions**

The results of this study reflect that natural gas trading companies in the liberalized market distinguish in significantly di fferent business risks' portfolios from those that operate under monopoly conditions; there, the main risk concern is security of supply [86,87]. It is also di fficult to evaluate the business risks' importance for the natural gas trading companies acting in liberalized markets because they characterize in hierarchical structures, which means that they are prone to cascading e ffects.

Nevertheless, when assessing business risks, according to the probability of their manifestation and potential damage to the gas trading company, we have identified that business risks a ffecting such companies can be divided into primary risks (operating volume risk, purchase price risk, risk of customers' default, risk of supplier default) and secondary risks (personnel risk, product competition risk, technological risk, alternative energy risk, reputation risk).

The essential risk for the successful activity of natural gas trading companies is distinguished to be a risk of operating volume. As a result, in order to successfully operate in the liberalized natural gas trading market, natural gas trading companies should pay especially grea<sup>t</sup> attention to the managemen<sup>t</sup> and prognostication of the mentioned risk.

**Author Contributions:** M.M. created a research concept, theoretical background and methodology, G.C. completed survey and obtained results, G.G. drew conclusions and provided valuable comments throughout the whole document.

**Funding:** This research received no external funding.

**Conflicts of Interest:** Authors declare no conflict of interests.
