In Wall v Stadt Frankfurt am Main (Case C-91/08, judgment of 13 April 2010), the CJEU held that a change of subcontractor (even if the possibility of a change is provided for in the contract) may in exceptional cases constitute a material amendment to the contract where the use of a particular subcontractor was a decisive factor in awarding the contract. The case concerned a service concession contract for the operation, maintenance, servicing and cleaning of 11 municipal public lavatories. The successful contractor indicated in its tender that it would utilise Wall as a subcontractor to provide marketing of the advertising surfaces and related equipment. Following signature of the contract, the successful tenderer informed Wall that its services would not be required as it had received a more competitive offer from another subcontractor. The successful contractor sought the consent of the contracting authority under the contract to change subcontractor. Wall initiated proceedings and a preliminary reference was made to the CJEU. The Court relied on the Pressetext case in clarifying that a change in subcontractor could constitute a material change to the contract awarded contrary to the principles of equal treatment and transparency. It is a matter for the national court to determine whether the facts of the case give rise to a material change.