(12)It is desirable to lay down rules defining the preconditions under which a management company may delegate, on the basis of mandates, specific tasks and functions to third parties so as to increase the efficiency of the conduct of its business. In order to ensure the correct functioning of the principles of mutual recognition of the authorisation and of the home country control, Member States permitting such delegations should ensure that the management company to which they granted an authorisation does not delegate globally its functions to one or more third parties, so as to become a letter box entity, and the existence of mandates does not hinder an effective supervision over the management company. However, the fact that the management company has delegated its own functions should in no case affect the liabilities of that company and of the depositary vis-à-vis the unit holders and the competent authorities.