Notwithstanding Article 28 and provided that the joint venture has been set up in order to carry out the activity concerned over a period of at least three years and that the instrument setting up the joint venture stipulates that the contracting entities, which form it, will be part thereof for at least the same period, this Directive shall not apply to contracts awarded by any of the following:

(a) by a joint venture, formed exclusively by a number of contracting entities for the purpose of carrying out activities within the meaning of Articles 8 to 14, to one of those contracting entities; or

(b) by a contracting entity to such a joint venture of which it forms part.