To do so, contracting authorities should, before rejecting those tenders, request in writing details of the constituent elements of the tender which are considered relevant for the appraisal or verification of its apparent anomaly, such as: the economics of the manufacturing process, of the services provided or of the construction method; technical solutions chosen or exceptionally favourable conditions available to the tenderer for the supply of the products or services or for the execution of the work; originality of the work, supplies or services proposed by the tenderer; compliance with the environmental, labour and social obligations referred to in reg.56(2); compliance with the subcontracting obligations established in reg.71 and the possibility of the tenderer obtaining State aid [reg.69(2) PCR2015]. I will not touch upon the issue of abnormally low tenders tainted with State aid [for that, see A Sanchez Graells, 'Enforcement of State Aid Rules for Services of General Economic Interest before Public Procurement Review Bodies and Courts' (2014) 10(1) Competition Law Review 3-34].
In view of the evidence supplied by the tenderer upon consultation, the contracting authority shall verify those constituent elements and reach a final decision on whether to reject the apparently abnormally low tender or not [reg.69(3) PCR2015; for a discussion of the standard applicable to the justification of this decision, particularly in the context of a challenge to that decision, see Case T-638/11 European Dynamics Belgium and Others v EMA  pub. electr. EU:T:2013:530.].
It has been stressed by EU case law that this is ‘a fundamental requirement in the field of public procurement, which obliges a contracting authority to verify, after due hearing of the parties and having regard to its constituent elements, every tender appearing to be abnormally low before rejecting it’ [Case T-495/04 Belfass  ECR II-781 98. Similarly, Joined Cases C-285/99 and C-286/99 Lombardini and Mantovani  ECR I-9233 51]. Indeed, as the CJEU has clearly emphasised, this is a positive and unavoidable requirement, and ‘Article 55 of Directive 2004/18 [now art 69 dir 2014/24] does preclude … a contracting authority from claiming … that it is not obliged to request a tenderer to clarify an abnormally low price’ [Case C-599/10 Slovensko  ECR I-10873 34].
under a duty, first, to identify suspect tenders, secondly to allow the undertakings concerned to demonstrate their genuineness by asking them to provide the details which it considers appropriate, thirdly to assess the merits of the explanations provided by the persons concerned, and, fourthly, to take a decision as to whether to admit or reject those tenders [Joined Cases C-285/99 and C-286/99 Lombardini and Mantovani  ECR I-9233 55].Hence, the rules of the directive exclusively impose procedural guarantees to be complied with by contracting authorities prior to rejecting apparently abnormally low tenders, and, consequently, seem to be mainly oriented towards providing affected tenderers with the opportunity to demonstrate that their tenders are genuine—ie, are primarily a mechanism to prevent discretionary (or arbitrary) decisions by contracting authorities. In this regard, contracting authorities are obliged to take into account the explanations and proof provided by the affected tenderers and, consequently, cannot apply automatic or simple mathematic rules to reject apparently abnormal tenders—although the use of such rules to identify suspicious tenders should not be ruled out.
As stressed by the case law, the directives do not provide a definition of ‘abnormally low tenders’, or a method to calculate an ‘anomaly threshold’—which are issues consequently left to Member States’ domestic regulation, and should be determined for each contract according to the specific purpose it is intended to fulfill (ie, it must be tender-specific). Therefore, the rules of the directives seem to be adequately conceived as a check or balance to the general power of contracting authorities to reject abnormally low tenders—which is an instance of exercise of their broad discretion with regard to the factors to be taken into account for the purpose of deciding to award a contract, or not to award it to a given tenderer.
The justification for this empowerment of contracting authorities to reject abnormally low tenders seems to be that they should not be forced to award the contract under circumstances where there is a reasonable risk of non-performance of the contract or of financial instability or disequilibrium, or a risk of breach of applicable legislation by the contractor during the execution of the contract under the tendered conditions (particularly as regards labour and risk prevention legislation, which have now been transformed into mandatory rejection grounds for abnormally low tenders); since such an award would hardly satisfy the needs of the contracting authorities and/or would force them to assume certain risks that they might not be willing to accept. The appraisal of such risks must be undertaken by contracting authorities from a neutral or objective perspective and be sufficiently motivated [by analogy with reg.69(4) PCR2015].