European Union – Public procurement. Article 2 of Directive (EC) 2004/18 should be interpreted as meaning that, failing any express legislative provision or specific condition in the call for tenders or in the tender specifications governing the conditions for the award of a public contract, related tenderers submitting separate offers in the same procedure were not obliged to disclose, on their own initiative, the links between them to the contracting authority. The Court of Justice of the European Union so held, among other things, in proceedings concerning the award of a public service contract relating to the collection of communal waste.