28Where a holding company makes capital available to its subsidiaries, that activity may of itself be considered an economic activity, consisting in exploiting that capital with a view to obtaining income by way of interest therefrom on a continuing basis, provided that it is not carried out merely on an occasional basis and is not confined to managing an investment portfolio in the same way as a private investor (see, to that effect, Case C-155/94Wellcome Trust v Commissioners for Customs and Excise [1996] ECR I-3013, paragraph 36; and Case C-230/94Enkler v Finanzamt Homburg [1996] ECR I-4517, paragraph 20) and provided that it is carried out with a business or commercial purpose characterised by, in particular, a concern to maximise returns on capital investment.