17. Utilities must provide the European Commission with the following information if the Commission so requests—
(a)the name of any undertaking or joint venture referred to in regulation 15 (exclusions: concession contracts awarded to an affiliated undertaking) or regulation 16 (exclusions: concession contracts awarded to a joint venture or to a utility forming part of a joint venture);
(b)the nature and value of any concession contract referred to in those regulations;
(c)proof, as considered necessary by the European Commission, that the relationship between the undertaking, joint venture or utility to which the concession contract is awarded and the utility or, as the case may be, joint venture, complies with the requirements of those regulations.