Settlement agreements bringing an end to a dispute cannot always be concluded.

On 7 September 2016, the Court of the European Union considered that "following the award of a public contract, a material amendment cannot be made to that contract without a new tendering procedure being initiated even in the case where that amendment is, objectively, a type of settlement agreement, with both parties agreeing to mutual waivers, designed to bring an end to a dispute the outcome of which is uncertain, which arose from the difficulties encountered in the performance of that contract.

The position would be different only if the contract documents provided for the possibility of adjusting certain conditions, even material ones, after the contract had been awarded and fixed the detailed rules for the application of that possibility".

"According to the Court, the principle of equal treatment and the obligation of transparency preclude, following the award of a public contract, the contracting authority and the successful tenderer from amending the provisions of that contract in such a way that those provisions differ materially in character from those of the original contract. Such will be the case if the proposed amendments would either extend the scope of the contract considerably to encompass elements not initially covered or to change the economic balance of the contract in favour of the successful tenderer, or if those changes are liable to call into question the award of the contract, in the sense that, had such amendments been incorporated in the documents which had governed the original contract award procedure, either another tender would have been accepted or other tenderers might have been admitted to that procedure".