This Agreement does not cover procurement:

a by a joint venture, formed exclusively by a number of procuring entities for the purpose of carrying out activities within the meaning of paragraphs (a) to (e) of this Annex, from one of these procuring entities; or

b by a procuring entity from such a joint venture of which it forms part, 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 procuring entities, which form it, will be part thereof for at least the same period.