The system used for measuring diversification effects referred to in Article 121(5) of Directive 2009/138/EC shall only be considered adequate where all of the following conditions are met:
(a) the system used for measuring diversification effects identifies the key variables driving dependencies;
(b) the system used for measuring diversification effects takes into account all of the following:
(i) any non-linear dependence and any lack of diversification under extreme scenarios;
(ii) any restrictions of diversification which arise from the existence of a ring-fenced fund or matching adjustment portfolio;
(iii) the characteristics of the risk measure used in the internal model;
(c) the assumptions underlying the system used for measuring diversification effects are justified on an empirical basis.