DYKA Plastics NV v Fluvius System Operator CV (C-424/23)

Contents

Judgment of the Court (Fourth Chamber)16 January 2025^note(Reference for a preliminary ruling — Award of public works contracts — Directive 2014/24/EU — Article 42 — Technical specifications — Formulation — Whether the list at Article 42(3) is exhaustive in nature — Invitation to tender requiring drainage work to be carried out using pipes made of vitrified clay and made of concrete — Plastic pipes excluded — Article 42(4) — Reference to a type or to a specific production — Situations in which a reference must be accompanied by the words or equivalent)In Case C‑424/23,REQUEST for a preliminary ruling under Article 267 TFEU from the ondernemingsrechtbank Gent, afdeling Gent (Ghent Business Court, Ghent Division, Belgium), made by decision of 28 June 2023, received at the Court on 11 July 2023, in the proceedingsDYKA Plastics NVvFluvius System Operator CV,THE COURT (Fourth Chamber),composed of K. Lenaerts, President of the Court, acting as President of the Fourth Chamber, C. Lycourgos (Rapporteur), President of the Third Chamber, S. Rodin, D. Gratsias and O. Spineanu-Matei, Judges,Advocate General: M. Campos Sánchez-Bordona,Registrar: A. Lamote, Administrator,having regard to the written procedure and further to the hearing on 30 May 2024,after considering the observations submitted on behalf of:– DYKA Plastics NV, by S. Van Garsse and S. Verhoeven, advocaten,– Fluvius System Operator CV, by E. Gypen and G. Laenen, advocaten,– the Czech Government, by L. Halajová, M. Smolek and J. Vláčil, acting as Agents,– the Austrian Government, by J. Schmoll and C. Pesendorfer, acting as Agents,– the European Commission, by G. Gattinara and G. Wils, acting as Agents,after hearing the Opinion of the Advocate General at the sitting on 12 September 2024,gives the following

Judgment

1This request for a preliminary ruling concerns the interpretation of Article 42 of Directive 2014/24/EU of the European Parliament and of the Council of 26 February 2014 on public procurement and repealing Directive 2004/18/EC (OJ 2014 L 94, p. 65).

2The request has been made in proceedings between DYKA Plastics NV (‘DYKA’) and Fluvius System Operator CV (‘Fluvius’) concerning the award by Fluvius of public contracts for drainage works, in the context of which it requires the use of sewage pipes made of vitrified clay and of concrete.

Legal context

European Union law

3Recitals 74 and 92 of Directive 2014/24 state:(74) The technical specifications drawn up by public purchasers need to allow public procurement to be open to competition as well as to achieve objectives of sustainability. To that end, it should be possible to submit tenders that reflect the diversity of technical solutions, standards and technical specifications in the marketplace, including those drawn up on the basis of performance criteria linked to the life cycle and the sustainability of the production process of the works, supplies and services.Consequently, technical specifications should be drafted in such a way as to avoid artificially narrowing down competition through requirements that favour a specific economic operator by mirroring key characteristics of the supplies, services or works habitually offered by that economic operator. Drawing up the technical specifications in terms of functional and performance requirements generally allows that objective to be achieved in the best way possible. Functional and performance-related requirements are also appropriate means to favour innovation in public procurement and should be used as widely as possible. Where reference is made to a European standard or, in the absence thereof, to a national standard, tenders based on equivalent arrangements should be considered by contracting authorities. ………(92) When assessing the best price-quality ratio contracting authorities should determine the economic and qualitative criteria linked to the subject matter of the contract that they will use for that purpose. Those criteria should thus allow for a comparative assessment of the level of performance offered by each tender in the light of the subject matter of the contract, as defined in the technical specifications. ……’

4In Article 1 of that directive, entitled ‘Subject matter and scope’, paragraph 2 thereof states:‘Procurement within the meaning of this Directive is the acquisition by means of a public contract of works, supplies or services by one or more contracting authorities from economic operators chosen by those contracting authorities, whether or not the works, supplies or services are intended for a public purpose.’

5Article 18 of that directive, entitled ‘Principles of procurement’, provides at paragraph 1 thereof:‘Contracting authorities shall treat economic operators equally and without discrimination and shall act in a transparent and proportionate manner.The design of the procurement shall not be made with the intention of excluding it from the scope of this Directive or of artificially narrowing competition. Competition shall be considered to be artificially narrowed where the design of the procurement is made with the intention of unduly favouring or disadvantaging certain economic operators.’

6Article 42 of that directive, entitled ‘Technical specifications’ provides:1. The technical specifications as defined in point 1 of Annex VII shall be set out in the procurement documents. The technical specification shall lay down the characteristics required of a works, service or supply.Those characteristics may also refer to the specific process or method of production or provision of the requested works, supplies or services or to a specific process for another stage of its life cycle even where such factors do not form part of their material substance provided that they are linked to the subject matter of the contract and proportionate to its value and its objectives.…2. Technical specifications shall afford equal access of economic operators to the procurement procedure and shall not have the effect of creating unjustified obstacles to the opening up of public procurement to competition.3.Without prejudice to mandatory national technical rules, to the extent that they are compatible with Union law, the technical specifications shall be formulated in one of the following ways:(a) in terms of performance or functional requirements, including environmental characteristics, provided that the parameters are sufficiently precise to allow tenderers to determine the subject matter of the contract and to allow contracting authorities to award the contract;(b) by reference to technical specifications and, in order of preference, to national standards transposing European standards, European Technical Assessments, common technical specifications, international standards, other technical reference systems established by the European standardisation bodies or – when any of those do not exist – national standards, national technical approvals or national technical specifications relating to the design, calculation and execution of the works and use of the supplies; each reference shall be accompanied by the words “or equivalent”;(c) in terms of performance or functional requirements referred to in point (a), with reference to the technical specifications referred to in point (b) as a means of presuming conformity with such performance or functional requirements;(d) by reference to the technical specifications referred to in point (b) for certain characteristics, and by reference to the performance or functional requirements referred to in point (a) for other characteristics.4. Unless justified by the subject matter of the contract, technical specifications shall not refer to a specific make or source, or to a particular process which characterises the products or services provided by a specific economic operator, or to trade marks, patents, types or a specific origin or production with the effect of favouring or eliminating certain undertakings or certain products. Such reference shall be permitted on an exceptional basis, where a sufficiently precise and intelligible description of the subject matter of the contract pursuant to paragraph 3 is not possible. Such reference shall be accompanied by the words “or equivalent”.…’

7Annex VII to Directive 2014/24, entitled ‘Definition of certain technical specifications’, provides:‘For the purpose of this Directive:(1) ‘technical specification’ means one of the following:(a) in the case of public works contracts the totality of the technical prescriptions contained in particular in the procurement documents, defining the characteristics required of a material, product or supply, so that it fulfils the use for which it is intended by the contracting authority; those characteristics include levels of environmental and climate performance, design for all requirements (including accessibility for disabled persons) and conformity assessment, performance, safety or dimensions, including the procedures concerning quality assurance, terminology, symbols, testing and test methods, packaging, marking and labelling, user instructions and production processes and methods at any stage of the life cycle of the works; those characteristics also include rules relating to design and costing, the test, inspection and acceptance conditions for works and methods or techniques of construction and all other technical conditions which the contracting authority is in a position to prescribe, under general or specific regulations, in relation to the finished works and to the materials or parts which they involve;…’

Belgian law

8The first paragraph of Article 4 of the wet inzake overheidsopdrachten (Law on public procurement) of 17 June 2016 (Belgisch Staatsblad, 14 July 2016, p. 44219) provides as follows:‘Contracting authorities shall treat economic operators equally and without discrimination and shall act in a transparent and proportionate manner.’

9Article 5(1) of that law is worded as follows:‘A contracting authority may not design a public contract with the intention of excluding it from the scope of this Law or of artificially narrowing competition. Competition shall be considered to be artificially narrowed where the design of the procurement is made with the intention of unduly favouring or disadvantaging certain economic operators.…’

10Article 53(2) to (4) of that Law provides:2. Technical specifications shall afford equal access of economic operators to the procurement procedure and may not have the effect of creating unjustified obstacles to the opening up of public procurement to competition.3.Without prejudice to mandatory national technical rules, to the extent that they are compatible with EU law, the technical specifications shall be formulated in one of the following ways:1° in terms of performance or functional requirements, including environmental characteristics, provided that the parameters are sufficiently precise to allow tenderers to determine the subject matter of the contract and to allow contracting authorities to award the contract;2° by reference to technical specifications and, in order of preference, to national standards transposing European standards, European Technical Assessments, common technical specifications, international standards, other technical reference systems established by the European standardisation bodies or – when any of those do not exist – national standards, national technical approvals or national technical specifications relating to the design, calculation and execution of the works and use of the supplies; Each reference shall be accompanied by the words “or equivalent”;3° either in terms of performance or functional requirements as referred to in point 1°, with reference to the specifications mentioned in point 2° as a means of presuming conformity with such performance or functional requirements;4° or by reference to the specifications mentioned in point 2° for certain characteristics, and by reference to the performance or functional requirements referred to in point 1° for other characteristics.4. Technical specifications may not refer to a specific make or source, or to a particular process which characterises the products or services provided by a specific economic operator, or to trade marks, patents, types or a specific origin or production with the effect of favouring or eliminating certain undertakings or certain products.Such reference shall be permitted, on an exceptional basis, only:1° where a sufficiently precise and intelligible description of the subject of the contract pursuant to paragraph 3 is not possible;2° where justified by the subject matter of the contract.In the situation referred to in paragraph 2(1°), the reference must be accompanied by the words ‘or equivalent’.…’

The dispute in the main proceedings and the questions referred for a preliminary ruling

11Fluvius is a company incorporated under Belgian law which is, in the Flanders Region, responsible for the construction, management and maintenance of a number of public utility networks, including sewerage networks.

12When publishing public contract notices for the installation or replacement of sewers, Fluvius requires the use of vitrified clay pipes for sewage disposal systems and concrete pipes for rainwater disposal systems. The use of other materials is permitted only in specific technical circumstances.

13As a manufacturer and supplier of sewage pipes made of plastic, DYKA believes that its exclusion from the public procurement procedures organised by Fluvius infringes the principles of public procurement laid down in Articles 4, 5 and 53 of the Law on public procurement, which implement Articles 18 and 42 of Directive 2014/24.

14On 4 June 2020, DYKA gave Fluvius formal notice to adapt its calls for tender so that it would be possible to offer sewage pipes made of plastic in such calls for tenders.

15Furthermore, on 7 October 2020, DYKA requested Fluvius to state, in the tender documents relating to a public contract for the installation of sewerage in the municipality of Beringen (Belgium), the reasons why plastic pipes were excluded from that contract.

16In its reply dated 15 October 2020, Fluvius confirmed that only pipes made of vitrified clay, in respect of disposal of sewage, and pipes made of concrete, in respect of disposal of rainwater, would be accepted. It takes the view that it does not have to give further reasons for that choice of materials.

17DYKA brought an action before the ondernemingsrechtbank Gent, afdeling Gent (Business Court, Ghent, Ghent Division, Belgium), which is the referring court, requesting it to order Fluvius to put an end to that practice and to order it to pay compensation.

18Before that court, Fluvius maintains that it is legitimate, in particular from the point of view of sustainability, to opt by default, that is to say, in the absence of specific technical circumstances, for sewage pipes made of vitrified clay and of concrete. It takes the view, in essence, that such a requirement does not infringe the principles set out in Articles 18 and 42 of Directive 2014/24.

19The referring court observes that it follows from Article 42 of Directive 2014/24 that technical specifications must be drafted so as to avoid artificially narrowing down competition. As is apparent from Article 42(3), read in conjunction with recital 74 of that directive, the formulation of technical specifications in terms of functional and performance requirements generally allows the objective of opening up to competition to be achieved in the best way possible.

20That court does not rule out the possibility that Article 42(3) of Directive 2014/24 must be interpreted as meaning that the contracting authority is required to draw up the technical specifications in accordance with one of the methods listed in that provision. However, it appears that the formulation used by Fluvius, consisting of referring to pipes made of vitrified clay and of concrete, does not accord with any of those formulation methods and that, moreover, it has the effect of eliminating certain undertakings or certain products, which could fall within the prohibition laid down in Article 42(4) of that directive. It is possible that regard has not been had to the principles set out in Article 18(1) and Article 42(2) of that directive.

21In those circumstances, the ondernemingsrechtbank Gent, afdeling Gent (Business Court, Ghent, Ghent Division) decided to stay the proceedings and to refer the following questions to the Court of Justice for a preliminary ruling:(1) Must Article 42(3) of Directive [2014/24] be interpreted as meaning that the list of ways in which the technical specifications must be formulated is of an exhaustive nature and that, a contracting authority consequently is obliged to formulate the technical specifications of its public contracts in one of the ways listed in that provision?(2) Must Article 42(4) of Directive [2014/24] be interpreted as meaning that references to sewage pipes made of vitrified clay and concrete (depending on the specific type of sewage system) in the technical specifications of calls for tender are to be regarded as falling within one or more of the references listed in that provision, for example, as references to specific types, or to specific productions of pipes?(3) Must Article 42(4) of Directive [2014/24] be interpreted as meaning that references in the technical specifications of calls for tender to a single product, for example, to sewage pipes made of vitrified clay and concrete (depending on the specific type of sewage system) as constituting specific technical solutions, already produce the effect required by that provision (namely “favouring or eliminating certain undertakings or certain products”) since they have the effect of excluding a priori and thus disadvantaging, undertakings which offer alternative solutions to the specified product, despite the fact that different undertakings in competition with each other are able to offer the prescribed specified product, or is it necessary that there be no competition whatsoever with regard to the product in question, for example, sewage pipes made of vitrified clay and concrete (depending on the specific type of sewage system) and that the effect referred to can therefore be said to exist only if the product in question is characteristic of one particular undertaking which alone offers it on the market?(4) Must Article 42(2) of Directive [2014/24] be interpreted as meaning that an established infringement of Article 42(3) of Directive [2014/24] and/or of Article 42(4) of Directive [2014/24], by virtue of the unlawful use of references in the technical specifications of calls for tender, for example, to sewage pipes made of vitrified clay and concrete (depending on the specific type of sewage system), also at the outset implies an infringement of Article 42(2) of Directive [2014/24], as well as of the related Article 18(1) of Directive [2014/24]?’

Consideration of the questions referred

Preliminary observations

22As a preliminary point, it must be stated that, in its written observations, the European Commission queries the applicable directive.

23It should be recalled that a question referred for a preliminary ruling must be examined in the light of all the provisions of the Treaties and of secondary legislation which may be relevant to the issue raised. The fact that a national court’s question refers to certain provisions of EU law does not mean therefore that the Court of Justice may not provide the national court with all the guidance on points of interpretation that may be of assistance in adjudicating on the case pending before it, whether or not that court has referred to those points in its question (judgment of 16 June 2022, Obshtina Razlog, C‑376/21, EU:C:2022:472, paragraph 51 and the case-law cited).

24Fluvius is responsible for installing, managing and maintaining sewerage systems. The works related to that activity are, as a general rule, governed by Directive 2014/24, by virtue of Article 1(2) thereof.

25However, Article 10(1) of Directive 2014/25/EU of the European Parliament and of the Council of 26 February 2014 on procurement by entities operating in the water, energy, transport and postal services sectors and repealing Directive 2004/17/EC (OJ 2014 L 94, p. 243) provides that activities connected with the transport and distribution of drinking water or with the supply of drinking water fall within the scope of that directive. Article 10(2)(b) of Directive 2014/25 states, in that regard, that contracts or design contests awarded or organised by contracting entities carrying out an activity referred to in Article 10(1) of that directive and which are connected with the disposal or treatment of sewage also fall within the scope of that directive.

26It is not clear from the request for a preliminary ruling whether Fluvius, as a contracting authority, carries out an activity connected with the transport and distribution of drinking water or the supply of drinking water. However, at the hearing, Fluvius, supported by the Commission and DYKA, stated that it was not active in that area. Accordingly, it appears, subject to verification by the referring court, that Directive 2014/24 applies in the present case.

27In any event, it should be noted that the provisions relating to technical specifications in Directive 2014/24 and in Directive 2014/25 are substantially the same.

The first question

28By its first question, the referring court is asking, in essence, whether Article 42(3) of Directive 2014/24 must be interpreted as meaning that the list, in that provision, of the methods for formulating technical specifications is exhaustive.

29In that regard, it must be stated that, under Article 42(3) of Directive 2014/24, the technical specifications are to be drawn up in accordance with point (a) of that provision, in terms of performance or functional requirements, or in accordance with point (b) of that provision, by reference to technical specifications, and, in order of preference, to national standards transposing European standards, European Technical Assessments, common technical specifications, international standards, other technical reference systems established by the European standardisation bodies or – when any of those do not exist – national standards, national technical approvals or national technical specifications relating to the design, calculation and execution of the works and use of the supplies, or indeed, in accordance with points (c) or (d) of that provision, a combination of both ways. There is no hierarchy among the methods of formulation of the technical specifications listed in points (a) to (d) of Article 42(3) of that directive (see, to that effect, judgment of 25 October 2018, Roche Lietuva, C‑413/17, EU:C:2018:865, paragraphs 26 and 28).

30As is apparent from the phrase ‘the technical specifications shall be formulated in one of the following ways’, which precedes points (a) to (d), it is for the contracting authority to draw up the technical specifications in accordance with one of those points and not in accordance with another method. Consequently, Article 42(3) of Directive 2014/24 must, as was observed, in essence, in point 44 of the Advocate General’s Opinion, be understood as meaning that it provides an exhaustive list of the methods for formulating the technical specifications which must appear in the procurement documents. If the EU legislature had intended to allow additional methods, it would have expressed its intention by using wording to that effect, such as ‘may be formulated’.

31That interpretation is not invalidated by the clarification, which appears at the beginning of Article 42(3) of Directive 2014/24, that that provision is ‘without prejudice to mandatory national technical rules, to the extent that they are compatible with Union law’. While it is true that that clarification may, where there is a national technical rule, lead to situations in which contracting authorities may derogate from the rule laid down in Article 42(3), it does not alter, as such, the meaning of that rule. Where, as in the present case, no ‘mandatory national technical rule’ is relied upon, the technical specifications must, without prejudice to Article 42(4) of that directive, be formulated in accordance with one of the methods laid down in points (a) to (d) of Article 42(3) of Directive 2014/24.

32That interpretation is also not invalidated by the statement, in the second sentence of Article 42(4) of Directive 2014/24, that there may be situations ‘where a sufficiently precise and intelligible description of the subject matter of the contract pursuant to paragraph 3 [of Article 42 of that directive] is not possible’.

33According to the second and third sentences of Article 42(4) of that directive, the contracting authority may, in such cases, exceptionally refer to a specific make or source, to a particular process or to another specific element referred to in the first sentence of paragraph 4 of Article 42, by adding the words ‘or equivalent’.

34Where that exception applies, on account of a sufficiently precise and intelligible description of the subject matter of the contract not being possible in accordance with Article 42(3) of Directive 2014/24, the contracting authority may include in the technical specifications a reference to the elements to which a reference is in principle prohibited by the first sentence of Article 42(4) of that directive, in so far as that reference is accompanied by the words ‘or equivalent’.

35Furthermore, in so far as the first sentence of Article 42(4) of Directive 2014/24 states that the prohibition on using the references mentioned therein does not apply where such a reference is justified by the subject matter of the contract, it must be held that that situation involves a derogation – as with the situation provided for in the second sentence of Article 42(4) of that directive, referred to in paragraphs 32 to 34 of the present judgment – from the exclusive applicability of the methods for formulating the technical specifications listed in Article 42(3).

36That being the case, apart from the situations set out in Article 42(4) of that directive and in the absence of any mandatory national technical rule, within the meaning of Article 42(3), the list of methods for formulating technical specifications listed in Article 42(3)(a) to (d) of Directive 2014/24 must be regarded as being exhaustive.

37As is apparent from all the foregoing considerations, the interpretation set out in paragraph 30 of the present judgment, which follows clearly from the words ‘shall be formulated in one of the following ways’ found in Article 42(3) of Directive 2014/24, applies in principle, that is to say, without prejudice (i) to the clarification found at the beginning of that provision, and (ii) to those clarifications contained in Article 42(4) of that directive. In the light of the Court’s settled case-law, in accordance with which, where the meaning of a provision of EU law is absolutely plain from its very wording, the Court cannot depart from that interpretation (judgment of 4 October 2024, Agentsia po vpisvaniyata, C‑200/23, EU:C:2024:827, paragraph 56 and the case-law cited), there is no need to examine further the scope of Article 42(3) of that directive.

38Consequently, the answer to the first question is that Article 42(3) of Directive 2014/24 must be interpreted as meaning that the list, in that provision, of the methods for formulating technical specifications is exhaustive, without prejudice to mandatory national technical rules which are compatible with EU law, as referred to in that provision, and without prejudice to Article 42(4) of that directive.

The second and third questions

39By its second and third questions, which it is appropriate to examine together, the referring court is asking, in essence, whether Article 42(4) of Directive 2014/24 must be interpreted as meaning that contracting authorities may state, in the technical specifications of a public works contract, the materials of which the products proposed by the tenderers must be made.

40In that regard, it must be stated at the outset that, in a procedure for the award of a public works contract, the formulation of technical specifications is intended, in accordance with Article 42(1) of Directive 2014/24, to lay down ‘the characteristics required of a works’. In so far as they establish those characteristics, the technical specifications define, as is apparent from recital 92 of that directive, the very subject matter of the public contract.

41Those specifications may include, inter alia, in accordance with point 1(a) of Annex VII to that directive, the characteristics required ‘of a … product or supply, so that it fulfils the use for which it is intended by the contracting authority’. Those characteristics include, in particular, all the ‘technical conditions which the contracting authority is in a position to prescribe, under general or specific regulations, in relation to the finished works and to the materials or parts which they involve’.

42While contracting authorities enjoy a broad discretion in that regard, which is justified by the fact that they are better placed to know which supplies they need and the requirements which are necessary to achieve the desired results, Directive 2014/24 nonetheless sets certain limits with which they must comply. Contracting authorities must, in accordance with Article 42(2) of Directive 2014/24, read in conjunction with Article 18(1) thereof, ensure that the technical specifications afford equal access of economic operators to the procurement procedure and do not have the effect of creating unjustified obstacles to the opening up of public procurement to competition (see, to that effect, judgment of 25 October 2018, Roche Lietuva, C‑413/17, EU:C:2018:865, paragraphs 29 to 33).

43Similarly, it follows from recital 74 of that directive that technical specifications formulated with a view to the award of a public contract must open up that public contract to competition and therefore allow tenders to be submitted which reflect, inter alia, the diversity of technical solutions available in the marketplace (see, to that effect, judgments of 25 October 2018, Roche Lietuva, C‑413/17, EU:C:2018:865, paragraph 36, and of 24 October 2024, Obshtina Pleven, C‑513/23, EU:C:2024:917, paragraph 36).

44Recital 74 of that directive states that the formulation of technical specifications in terms of functional and performance requirements generally allows the objective of opening up to competition to be achieved in the best way possible and that, therefore, that method of formulation, which favours innovation in public procurement, should be used as widely as possible.

45Formulating the technical specifications in that manner, as referred to in Article 42(3)(a) of Directive 2014/24, allows any economic operator whose products meet the performance and functional requirements imposed by the contracting authority to submit a tender, irrespective, in particular, of the process used in manufacturing its products and the material of which those products are made.

46In order for the formulation method laid down in Article 42(3)(b) of Directive 2014/24 to ensure also sufficient opening up to competition, the EU legislature provided that the technical specifications formulated in accordance with that method must be accompanied by the words ‘or equivalent’.

47Since opening up to competition is thereby ensured where one of the methods referred to in Article 42(3)(a) and (b) of Directive 2014/24 is applied, it is also ensured in the cases referred to in Article 42(3)(c) and (d) of that directive, which consist of a combination of those two methods.

48By contrast, including a reference in technical specifications ‘to a specific make or source, or a particular process which characterises the products or services provided by a specific economic operator’, or ‘to trade marks, patents, types or a specific origin or production with the effect of favouring or eliminating certain undertakings or certain products’ is, in principle, prohibited under Article 42(4) of that directive.

49Such references, far from contributing to opening up a public contract to competition, have the effect of restricting competition.

50Nevertheless, on an exceptional basis, a contracting authority may, in the contract documents containing the technical specifications, include a reference mentioned in Article 42(4) of Directive 2014/24, provided that, as laid down, in essence, in the second sentence of that provision, the performance or functional requirements referred to in accordance with Article 42(3)(a) of that directive or the specifications– referred to in accordance with Article 42(3)(b) of that directive, or a combination of the two, do not, in themselves, make a sufficiently precise and intelligible description of the subject matter of the contract possible. In such a case, the contracting authority must, in accordance with the third sentence of Article 42(4) of that directive, accompany that reference with the words ‘or equivalent’.

51As is apparent, moreover, from the phrase ‘unless justified by the subject matter of the contract’, which is found in the first sentence of Article 42(4) of Directive 2014/24, the references referred to in that provision may also be made where that is legitimate in the light of the subject matter of the contract. Having regard to it being placed at the beginning of Article 42(4) and to the use of the word ‘unless’, that situation, which is distinct from the situation provided for in the second sentence of Article 42(4), must be understood as a circumstance which allows the contracting authority to disregard the very applicability of the normative content of paragraph 4, which contains the in principle prohibition set out in the first sentence of that paragraph, the exception to that prohibition laid down in the second sentence of that paragraph and the requirement, laid down in the third sentence thereof, to add, where that exception applies, the words ‘or equivalent’.

52Therefore, where a reference such as that mentioned in Article 42(4) of Directive 2014/24 is justified by the subject matter of the contract, it may be included in the technical specifications, without the prohibition set out in the first sentence of that provision or the conditions laid down in the second and third sentences thereof applying.

53That situation referred to by the words ‘unless justified by the subject matter of the contract’ must, if it is not to undermine the objective of opening up public procurement to competition, be interpreted restrictively, so that it covers only situations in which a requirement relating to the use of a product of a particular type or origin or of a particular trade mark, or obtained on the basis of a particular patent or particular process, follows inevitably from the subject matter of the contract.

54It is in the light of all the clarifications provided above concerning the scope of Article 42 of Directive 2014/24 that it will be for the referring court to assess whether or not Fluvius may limit, by means of the technical specifications which it formulates for the award of public contracts for sewerage works, those public contracts to economic operators which supply sewage pipes made of vitrified clay for the disposal of sewage and pipes made of concrete for the disposal of rainwater.

55While it will be for the referring court alone to apply the rules set out in Article 42, as interpreted by the Court, the Court may nevertheless provide guidance for the purpose of determining the extent to which those rules are capable of applying to a reference, such as that at issue in the main proceedings, consisting of a requirement to use pipes made of ‘vitrified clay’ and of ‘concrete’.

56In that regard, it must be stated, first, that the material of which a product is made cannot be classified as a ‘performance’ or ‘functional requirement’ within the meaning of Article 42(3)(a) of Directive 2014/24. While a material may contribute to the performance of a product or to its ability to meet a functional requirement, it does not constitute, in itself, a ‘performance’ or a ‘functional requirement’.

57In a situation such as that at issue in the main proceedings, where there are, in the economic sector concerned, products which are distinguishable according to their manufacture and, in particular, the material of which they are made, the requirement to use products made of a certain material must, as was observed in points 72 and 73 of the Advocate General’s Opinion, be classified as a reference to a ‘type’ or ‘specific production’ having ‘the effect of favouring or eliminating certain undertakings or certain products’ within the meaning of the first sentence of Article 42(4) of Directive 2014/24, since that reference leads to the elimination of undertakings which supply products made of a material other than that required.

58Second, it should be noted that, at the hearing before the Court, Fluvius stated, in response to a question put by the Court, that it had not had the technical specification at issue in the main proceedings, whereby the pipes for the disposal of sewage had to be made of vitrified clay and the pipes for the disposal of rainwater had to be made of concrete, accompanied by the words ‘or equivalent’.

59Should that be the case, which it is for the referring court to ascertain, it would follow – there being no need to examine whether pursuant to Article 42(3) of Directive 2014/24 a sufficiently precise and intelligible description of the subject matter of each contract at issue in the main proceedings was possible – that Fluvius could not properly rely on the exception laid down in point 1° of the second subparagraph of Article 53(4) of the Law on public procurement, which transposes the second sentence of Article 42(4) of that directive into Belgian law, since the requirement set out in the third sentence of Article 42(4), transposed into Belgian law by the third subparagraph of Article 53(4) of that law, would not be met.

60As regards, third, the situation referred to at the beginning of Article 42(4) of Directive 2014/24, interpreted in paragraphs 51 to 53 of the present judgment and transposed into Belgian law by point 2 of the second subparagraph of Article 53(4) of that law, it must be held that the requirement relating to the use of particular material for a public contract or part thereof may, in particular, follow inevitably from the subject matter of the contract where it is based on the aesthetic sought by the contracting authority, or on the need for a work to be in line with its environment, or where, in the light of a performance or functional requirement formulated pursuant to Article 42(3)(a) of that directive, the use of products made of that material is inevitable. In such situations, no alternative based on a different technical solution is conceivable.

61Where the use of a material does not follow inevitably from the subject matter of the contract, the contracting authority may not, without adding the words ‘or equivalent’, require a particular material to be used. It must then, in the context of technical specifications, refrain from requiring a particular material to be used, either by avoiding referring to such a material in the procurement documents or by referring to one or a number of materials while adding the words ‘or equivalent’. Thus, in accordance with the objective of opening up to competition pursued by Directive 2014/24, the contracting authority will need to apply the award criteria to a variety of tenders, which may include both those proposing products made of materials which are commonly used in the sector concerned and those proposing products made of materials which are less usual, or which are innovative. The contracting authority thereby provides interested economic operators with the opportunity to demonstrate that such materials are equivalent.

62In the light of the foregoing, the answer to the second and third questions is that Article 42(4) of Directive 2014/24 must be interpreted as meaning that contracting authorities may not, without adding the words ‘or equivalent’, state, in the technical specifications of a public works contract, the materials of which the products proposed by the tenderers must be made, unless the use of a particular material follows inevitably from the subject matter of the contract, it not being possible to contemplate an alternative based on a different technical solution.

The fourth question

63By its fourth question, the referring court is asking, in essence, whether Article 42(2) of Directive 2014/24, read in conjunction with Article 18(1) of that directive, must be interpreted as meaning that the obligation to afford economic operators equal access to public procurement procedures and the prohibition on creating unjustified obstacles to the opening up of public procurement to competition, set out in the latter provision, are necessarily infringed where a contracting authority eliminates certain undertakings or certain products by means of a technical specification which is incompatible with the rules set out in Article 42(3) and (4) of that directive.

64It is clear from the wording of Article 42(2) of Directive 2014/24 that the purpose of that provision is to recall, as regards the formulation of technical specifications, some of the rules set out in Article 18(1) of that directive, namely, first, the obligation to treat economic operators equally and, second, the prohibition on artificially narrowing competition (see, to that effect, judgment of 25 October 2018, Roche Lietuva, C‑413/17, EU:C:2018:865, paragraphs 32 to 33).

65That content of Article 42(2) of Directive 2014/24 is, in turn, given specific expression by Article 42(3) and (4) of that directive. As is apparent from the examination of the first to third questions referred for a preliminary ruling, those paragraphs also take as a basis, as is confirmed by recital 74 of Directive 2014/24, that obligation and that prohibition.

66Therefore, where certain undertakings or certain products are excluded on the basis of a technical specification which is incompatible with the rules set out in Article 42(3) and (4) of Directive 2014/24, that exclusion necessarily infringes the obligation, set out in Article 42(2) thereof, to ensure that technical specifications afford equal access to the procurement procedure and do not unduly restrict competition.

67Consequently, the answer to the fourth question referred is that Article 42(2) of Directive 2014/24, read in conjunction with Article 18(1) of that directive, must be interpreted as meaning that the obligation to afford economic operators equal access to public procurement procedures and the prohibition on creating unjustified obstacles to the opening up of public procurement to competition, set out in the latter provision, are necessarily infringed where a contracting authority eliminates certain undertakings or certain products by means of a technical specification which is incompatible with the rules set out in Article 42(3) and (4) of that directive.

Costs

68Since these proceedings are, for the parties to the main proceedings, a step in the action pending before the referring court, the decision on costs is a matter for that court. Costs incurred in submitting observations to the Court, other than the costs of those parties, are not recoverable.

Operative part

On those grounds, the Court (Fourth Chamber) hereby rules:

1.Article 42(3) of Directive 2014/24/EU of the European Parliament and of the Council of 26 February 2014 on public procurement and repealing Directive 2004/18/ECmust be interpreted as meaning that the list, in that provision, of the methods for formulating technical specifications is exhaustive, without prejudice to mandatory national technical rules which are compatible with EU law, as referred to in that provision, and without prejudice to Article 42(4) of that directive.

2.Article 42(4) of Directive 2014/24must be interpreted as meaning that contracting authorities may not, without adding the words ‘or equivalent’, state, in the technical specifications of a public works contract, the materials of which the products proposed by the tenderers must be made, unless the use of a particular material follows inevitably from the subject matter of the contract, it not being possible to contemplate an alternative based on a different technical solution.

3.Article 42(2) of Directive 2014/24, read in conjunction with Article 18(1) of that directive,must be interpreted as meaning that the obligation to afford economic operators equal access to public procurement procedures and the prohibition on creating unjustified obstacles to the opening up of public procurement to competition, set out in the latter provision, are necessarily infringed where a contracting authority eliminates certain undertakings or certain products by means of a technical specification which is incompatible with the rules set out in Article 42(3) and (4) of that directive.