1.

The request for a preliminary ruling from the Rechtbank van koophandel te Gent (Commercial Court, Ghent, Belgium), according to the wording of the question referred, concerns the interpretation of Article 45 TFEU on freedom of movement for workers.

2.

However, it is apparent from the decision to refer that the main proceedings and, therefore, the subject-matter of the request are in fact concerned with the free movement of goods and, more specifically, the prohibition of measures having an effect equivalent to quantitative restrictions on exports between Member States which is laid down in Article 35 TFEU.

3.

This request has been lodged in the course of a dispute between a company established in the Dutch-speaking region of the Kingdom of Belgium and a company established in Italy for failure by the latter company, which is connected to the Belgian company by a concession agreement, to pay a number of invoices. The invoices concerned were drawn up in Italian while, according to the referring court, under the Belgian legislation applicable to them, they should have been drawn up exclusively in Dutch, failing which they are be declared null and void by the courts of their own motion.

4.

In the light of the judgment in Las, ( 2 ) in which the Court ruled that the equivalent provisions of that legislation on employment contracts were incompatible with EU law, the referring court is uncertain whether the legislation is liable to produce a dissuasive effect also in relation to cross-border trading by Belgian companies established in the Flemish Region and consequently constitutes a prohibited restriction on the exercise of the freedoms of movement. Should that be the case, it then wonders whether such restrictive measures might be justified by one or more objectives in the public interest and, if so, whether they are proportionate to the objectives pursued.

5.

Under Article 4 of the Belgian Constitution, ( 3 )‘Belgium comprises four linguistic regions: the French-speaking region, the Dutch-speaking region, the bilingual region of Brussels-Capital and the German-speaking region’.

6.

Under Article 129(1)(3) of the Constitution, ‘[t]he Parliaments of the Flemish and French Communities, to the exclusion of the federal legislature, shall regulate by decree, each one as far as it is concerned, the use of languages for: … relations between employers and their staff, as well as company acts and documents required by the law and by regulations’. Those Communities are federal units of the Belgian State.

7.

Article 52(1) of the wetten op het gebruik van de talen in bestuurszaken (laws on the use of languages in administrative matters) ( 4 ) provides that ‘private industrial, commercial and financial undertakings shall use, for acts and documents required by the law and by regulations …, the language of the region in which they have their establishment or various establishments’.

8.

A vlaamse taaldecreet (decree on the use of languages) was adopted in 1973 by the Parlement van de Vlaamse Gemeenschap (Parliament of the Flemish Community) ( 5 ) on the basis of Article 129(1)(3) of the Constitution.

9.

Under Article 1 of that decree in the version in force at the material time in the main proceedings, that instrument ‘shall apply to natural and legal persons having an established place of business in the Dutch-speaking region’ and ‘shall regulate the use of languages with regard to relations between employers and employees, and with regard to company acts and documents required by the law’.

10.

Article 2 of the Decree provides that ‘the language to be used for relations between employers and employees, and for company acts and documents required by the law, shall be Dutch’. Article 5, first paragraph, adds that ‘[a]ll employers’ acts and documents required by the law shall be drawn up by the employer in the Dutch language …’.

11.

Article 10, first paragraph, of the Decree provides, in respect of penalties, that ‘[d]ocuments or acts which infringe the provisions of this Decree shall be null and void. Nullity shall be determined by the courts of their own motion’. The second and third paragraphs of that article provide that ‘[t]he judgment shall order that the relevant documents be replaced as a matter of course’ and that ‘[r]evocation of the nullity shall be effective only from the date of the substitution: for written documents, from the date of deposit of the substitute documents at the registry of the labour tribunal’.

12.

Following the judgment in Las, ( 6 ) various provisions of that decree were amended, although they did not come into force until 2 May 2014, ( 7 ) thus, after the facts arising in the main proceedings, and were concerned only with relations between employers and their employees, which are not the subject matter of this action.

13.

On 12 November 2010, New Valmar BVBA, which has its registered office in the Dutch-speaking region of the Kingdom of Belgium, and Global Pharmacies Partner Health Srl (‘GPPH’), a company established in Italy, concluded an agreement appointing GPPH as New Valmar’s exclusive concession-holder in Italy which would be valid until 31 December 2014.

14.

Under Article 18 of the concession agreement, the agreement was governed by Italian law and the courts in Ghent (Belgium) had jurisdiction to entertain any disputes that might arise between the parties.

15.

By registered letter of 29 December 2011, New Valmar terminated the agreement early, with effect from 1 June 2012.

16.

By a writ of summons of 30 March 2012, New Valmar brought an action before the Rechtbank van Koophandel te Gent (Commercial Court, Ghent) seeking an order requiring GPPH to pay to it a sum of approximately EUR 234192 in settlement of various outstanding invoices.

17.

GPPH filed a counterclaim seeking an order requiring New Valmar to pay EUR 1467448 in compensation for the wrongful termination of their concession agreement.

18.

Challenging the principal claim, GPPH contended that the invoices at issue were null and void on the ground that, although they are ‘acts and documents required by the law and by regulations’ within the meaning of the coordinated Laws and the Flemish Decree on the use of languages, those invoices infringed the public-policy rules contained in that legislation.

19.

It is also apparent from the decision to refer that, with the exception of the identifying particulars for New Valmar, and the value added tax (VAT) and bank details, all the standard information and the general terms and conditions on the invoices were set out in a language other than Dutch, namely in Italian, even though New Valmar is established in the Dutch-speaking region of the Kingdom of Belgium.

20.

On 14 January 2014, thus, in the course of the proceedings, New Valmar supplied to GPPH a translation into Dutch of the relevant invoices. The referring court states that such a translation is not equivalent to the ‘substitution’ required by the Flemish language legislation and that the contested invoices are and remain in their entirety null and void under Belgian law.

21.

New Valmar does not dispute that the invoices at issue fail to comply with that legislation. However, it claims inter alia that the legislation is contrary to EU law, in particular to Article 26(2) TFEU, and to Articles 34 and 35 TFEU concerning the free movement of goods.

22.

Against that background, by decision of 18 December 2014, received at the Court on 16 January 2015, the Rechtbank van Koophandel te Gent (Commercial Court, Ghent) decided to stay the proceedings before it and refer the following question to the Court of Justice for a preliminary ruling:

‘Must Article 45 TFEU be interpreted as precluding legislation of a federal unit of a Member State, such as, in the present case, the Vlaamse Gemeenschap in de federale Staat België (Flemish Community in the Federal State of Belgium), which requires every undertaking which has its place of establishment within the territory of that unit to draw up, pursuant to Article 52 of the [coordinated] Laws … in conjunction with Article 10 of the [Flemish Decree on the use of languages] …, invoices which are of cross-border character exclusively in the official language of that federal unit, on pain of nullity of those invoices, which nullity is to be determined by the courts of their own motion?’

23.

Written observations were submitted to the Court by New Valmar, the Belgian and Lithuanian Governments and the European Commission. New Valmar, the Belgian Government and the Commission were represented at the hearing held on 26 January 2016.

24.

Before addressing the substance of this request for a preliminary ruling, it is necessary to consider the merits of the question referred in various respects, taking account of the doubts expressed in the observations submitted to the Court.

25.

As the main proceedings have a cross-border element, it must first be verified that the provisions of Belgian law mentioned by the referring court are really intended to apply to the situation at issue in the main proceedings, as that court assumes to be the case. The Commission is right to raise the issues of conflicts of laws, even though the Court is not asked about this matter directly, as it is clear from the decision to refer that the concession agreement signed by the parties to these proceedings expressly provided that the agreement was to be subject to Italian law, not Belgian law which is the subject matter of the question referred for a preliminary ruling.

26.

In a contractual context, the choice of applicable law made by the parties must in principle be respected by the courts, in accordance with Article 3 of Regulation (EC) No 593/2008. ( 8 ) However, there are some qualifications attached to the fundamental principle of contractual autonomy, ( 9 ) in particular on account of the possible involvement of internationally mandatory provisions, or ‘overriding mandatory provisions’, in the strict circumstances provided for in Article 9 of that regulation, in which it is stated that recourse to such an exception must be reserved for ‘exceptional circumstances’. ( 10 )

27.

In the present case, it is possible for the Flemish language regime to be applicable in the main proceedings, notwithstanding the fact that the contracting parties chose Italian law, and thus, it is far from obvious that the request for a preliminary ruling is hypothetical, ( 11 ) in so far as the referring court considers the Flemish language regime that it proposes to apply to be an ‘overriding mandatory provision’ of the law of the forum within the meaning of Article 9 of Rome I, ( 12 ) a matter which it falls to that court to determine on the facts.

28.

In this regard, I would point out that Article 9(1) of Rome I defines the concept of overriding mandatory provisions as ‘provisions the respect for which is regarded as crucial by a country for safeguarding its public interests, such as its political, social or economic organisation’. Since that definition is not sufficient in itself to identify the national rules — among all the rules of a mandatory nature — that actually come under that concept, the courts of the Member States are required to state the grounds on which the relevant provisions of the law concerned must be applied in the specific circumstances, to the detriment of the law of another country. ( 13 ) In order to undertake such a classification, they must take into account an entire range of objective criteria, as the Court pointed out with regard to an instrument from which Rome I is derived. ( 14 )

29.

Assuming that the Flemish language regime must apply in the main proceedings, the content of the provisions applicable in this case must then be considered, bearing in mind the differences that can be identified between the presentation of the relevant national legislation set out in the decision to refer and that stemming from the written and oral observations of the Belgian Government.

30.

The Belgian Government does, after all, maintain that, contrary to what the referring court appears to acknowledge, that the Flemish language legislation does not lay down any statutory obligation or require any reference in the invoice to the terms of the invoice or the conditions of sale, or to include such references in Dutch. It submits that only the information required under VAT law ( 15 ) must necessarily be drafted in Dutch, pursuant to Article 2 of the Flemish Decree on the use of languages. ( 16 ) According to the Belgian Government, it is perfectly straightforward for the customer to understand those details which are for the most part expressed in figures or, where necessary, to consult a translation of the mandatory information in any of the languages of the European Union, since they correspond to those listed in a harmonised manner in Article 226 of Directive 2006/112/EC. ( 17 )

31.

According to settled case-law, where the content of the decision to refer is challenged by one of the parties to the preliminary ruling procedure, the Court must in principle confine its examination to the matters which the court or tribunal making the reference has decided to submit to it for consideration, in particular as regards the detailed rules for implementing the relevant national legislation that the referring court considers to be established, since the interpretation of provisions of national law is a matter exclusively for the courts of the Member States. ( 18 ) Therefore, irrespective of the criticism expressed by the Belgian Government with regard to the interpretation of national law adopted by the national court, this reference for a preliminary ruling must be considered in the light of that court’s interpretation of that law. ( 19 )

32.

However, the Court, when giving a preliminary ruling, may, where appropriate, provide clarification designed to give the national court guidance in its interpretation of a domestic law and in its assessment of its conformity with EU law. ( 20 ) In this case, in my view, it will fall to the referring court to ascertain more specifically the extent to which the language legislation concerned actually requires all the details set out in invoices issued by a company established in the Flemish Region to be drawn up exclusively in Dutch.

33.

Within the framework of the question it has referred, the Rechtbank seeks the guidance of the Court regarding the interpretation of Article 45 TFEU, which provides for the free movement of workers within the Union. However, it is clear to me that this is a substantive error, perhaps connected with the fact that the judgment in Las ( 21 ) — the authority to which the decision to refer principally refers — concerned that article.

34.

In any event, there is no doubt that the main proceedings do not fall within the scope of that provision, since they relate to the commercial relationship between a Belgian company on the one hand, and an Italian company on the other, with none of the documents in the case providing any link between the present dispute and the free movement of workers.

35.

The erroneous reference thus cited cannot, however, result in the inadmissibility of the request for a preliminary ruling, as the Belgian Government asserts as a principal claim. It is settled case-law that, in the procedure laid down by Article 267 TFEU, providing for cooperation between national courts and the Court of Justice, the latter may reformulate the questions referred to it in order to provide the referring court with a useful answer and which will enable it to determine the case before it. ( 22 )

36.

In this regard, it is for the Court to extract from all the information provided by the national court, in particular from the grounds of the decision to make the reference, the points of EU law which require interpretation in view of the subject matter of the dispute. ( 23 ) It is apparent from the grounds of the decision to make the reference that the applicant in the main proceedings, New Valmar, relied as its principal claim on the fact that the relevant national legislation infringes Article 26(2) TFEU and of Articles 34 and 35 TFEU and that, in the alternative, it requested the referring court to refer to the Court a question for a preliminary ruling specifically concerning those provisions of primary law relating to the free movement of goods.

37.

Like all the interested parties which submitted observations, namely New Valmar, the Belgian Government — in the alternative, the Lithuanian Government and the Commission, I therefore take the view that the question referred should be reformulated in such a manner that the request for a preliminary ruling in fact relates to the interpretation of the provisions of the FEU Treaty concerning the free movement of goods, and more specifically to Article 35 of the Treaty, for the reasons that I shall set out below.

38.

Although New Valmar relies on Article 26(2) TFEU and Articles 34 and 35 TFEU, it seems to me, however, that the latter provision alone corresponds directly to the subject-matter of the main proceedings and must therefore give rise to an interpretation in this case.

39.

It is clear from the decision to refer that this dispute, relating to the payment of invoices drawn up in Italian and not in Dutch, is concerned with supplies of goods by a party granting a concession which is established in Belgium to a concession-holder established in Italy. The question submitted to the Court therefore relates, in essence, to whether the linguistic requirements under the domestic legislation mentioned by the referring court may restrict such intra-Community exports of goods originating in Belgium.

40.

Article 26(2) TFEU merely makes a general reference to the principle of the free movement of goods, persons, services and capital within the internal market. Article 34 TFEU relates to measures having an equivalent effect to quantitative restrictions on imports and not to those relating to exports between Member States, which are prohibited by Article 35 TFEU. Therefore, national legislation such as that at issue in the main proceedings must be considered, in my opinion, more specifically in the light of Article 35 TFEU, as the Commission recommends.

41.

The Belgian Government alone submits that the conformity of the relevant national measures with EU law should be assessed exclusively in the light of the applicable rules of secondary law on VAT, and especially of Directive 2006/112, on the ground that the rules of primary law cannot be the reference standard as long as there is full harmonisation regarding the content of the invoices. ( 24 )

42.

It claims that Article 248a of that directive ( 25 ) allows Member States to require, in their domestic legislation, that invoices issued in a cross-border context be drafted in a language other than the language of the recipient. According to the Belgian Government, Directive 2006/112 even implies that invoices are, in principle, drawn up in the language of the Member State in which the undertaking issuing the invoice is established as, otherwise, the right conferred under Article 248a to request a translation into the official language of the Member State of destination of the goods, services or invoice would in that case be redundant. ( 26 )

43.

However, like the other interested parties submitting observations at the hearing, namely New Valmar and the Commission, I do not concur with the Belgian Government’s assessment for the reasons set out below.

44.

First of all, I should point out that the gradual harmonisation ( 27 ) by the directives successively adopted as regards VAT is not full but partial at this stage, as the Court has repeatedly held. ( 28 )

45.

As regards, more specifically, the ‘content of invoices’ required for VAT purposes by Directive 2006/112, although Section 4 which bears that title and comes under Chapter 3 on ‘[i]nvoicing’ comprises harmonising provisions in this area, in particular listing a series of mandatory information and prohibiting Member States from requiring invoices to be signed, ( 29 ) such harmonisation relates only to the content of invoices, not to the practical arrangement in accordance with which they must be drawn up. ( 30 ) Specifically, Section 4 lays down no binding provisions whatsoever as to the language that should be used in that context. Moreover, no other provisions of Directive 2006/112 set out harmonised language requirements for invoicing purposes.

46.

I would point out here that the scope of Article 248a of Directive 2006/112 is much narrower than that which the Belgian Government seeks to confer on that provision. After all, it is clear from its wording that the intention of the provision is not, by any means, to allow all Member States to require in principle that a specific language be used when drawing up invoices, and in particular not necessarily the language of the Member State in which the invoice is issued, as the Belgian Government maintains.

47.

Article 248a provides only for a possibility, not an obligation, for the Member State of destination to call for a straightforward translation into its official language, not for the invoice itself to be drafted in that language, ( 31 ) and only if considered to be necessary for the purpose of monitoring invoices which are stored by electronic means in another Member State, not on a systematic basis. ( 32 ) That article even expressly precludes the Member State of destination from imposing a general obligation that invoices be translated for control purposes, ( 33 ) bearing in mind that the mandatory translation of invoices ‘constitutes a not inconsiderable burden on businesses’, as was rightly pointed out in the course of the legislative work leading to the inclusion of that article in Directive 2006/112. ( 34 )

48.

Given that that provision represents a derogation in the light of the general tenor of Directive 2006/112, it must be applied strictly, the rule being and remaining that of the freedom of the parties to the economic relationship giving rise to cross-border invoices to choose the language to be used, as the Commission stated at the hearing. ( 35 )

49.

Consequently, in the absence of any exhaustive harmonisation by secondary EU law in the area covered by this request for a preliminary ruling, namely with regard to the language rules to be observed when drawing up cross-border invoices, the question referred should, in my opinion, be reformulated so as to relate to the interpretation of Article 35 TFEU. ( 36 )

50.

In essence, the question referred for a preliminary ruling, as reformulated, asks the Court to assess, first of all, whether national measures such as those mentioned have the effect of restricting trade between the Member States with the result that they constitute measures having an effect equivalent to a quantitative restriction on exports, for the purposes of Article 35 TFEU, and then, if so, whether such measures may nonetheless be regarded as compatible with EU law if they are justified by objectives in the public interest and are proportionate to those objectives.

51.

The referring court is unsure, in particular, whether the Court’s position in Las, ( 37 ) that the provisions on employment relations set out in the same language legislation as that at issue here were incompatible with freedom of movement for workers, ( 38 ) can be transposed to the circumstances of this case, which leads to an examination of that legislation in this instance with regard to the free movement of goods.

52.

As in the case giving rise to the Las judgment, ( 39 ) this case essentially concerns the potential incompatibility with EU law of a regime applicable in a Member State under which, where undertakings established in the territory of a federal unit of that State, in this case the Flemish Region of the Kingdom of Belgium, draw up certain documents, they must necessarily use the official language of that unit, that is to say, Dutch, failing which they must be declared null and void by the courts of their own motion, even though those documents are drawn up in the context of cross-border trade and the parties concerned might understand one another better if they were to use another language.

53.

In Las, in order to rule that such a regime was liable to have a dissuasive effect on non-Dutch-speaking employees and employers from other Member States and therefore constituted a restriction contrary to Article 45 TFEU, the Court held inter alia that such a measure, even though applicable without discrimination on grounds of nationality, was capable of rendering less attractive the exercise of the free movement of workers, given that only the Dutch text was authentic vis-à-vis the cross-border employment contracts concluded by employers established in the Flemish Region. ( 40 )

54.

That reasoning cannot be transposed automatically to the circumstances of this case because the Court’s assessment of conformity with Article 45 TFEU is not absolutely identical to the analysis that has to be undertaken in relation to Article 35 TFEU, the latter provision prohibiting measures having an effect equivalent to quantitative restrictions on exports, which are accordingly determined as such on the basis of criteria established in the case-law which are somewhat different from those applying to the free movement of workers.

55.

It is clear from the Court’s case-law that the measures prohibited under Article 35 TFEU are those ‘which have as their specific object or effect the restriction of patterns of exports and thereby the establishment of a difference in treatment between the domestic trade of a Member State and its export trade, in such a way as to provide a particular advantage for national production or for the domestic market of the State in question, at the expense of the production or trade of other Member States’. ( 41 )

56.

However, the Court relaxed that approach, in circumstances similar to those in this case, adding that ‘even if [national legislation] is applicable to all traders active in the national territory’, it can be considered to be a measure having an equivalent effect to a quantitative restriction on exports on condition that it is established that the ‘actual effect [of the legislation] is none the less greater on goods leaving the market of the exporting Member State than on the marketing of goods in the domestic market of that Member State’. ( 42 )

57.

Those are the criteria to be applied in this case for assessing whether the language legislation concerned may constitute a restrictive measure prohibited by Article 35 TFEU.

58.

In its request for a preliminary ruling, the referring court mentions various factors in support of the view that the Flemish language regime may constitute a restriction of the exercise of the freedoms of movement provided for in the Treaty. In opposition to the Belgian Government’s submissions, New Valmar and the Commission also put forward a series of arguments in favour of that critical approach, ( 43 ) that I too propose that the Court should adopt for the reasons set out below.

59.

The language regime at issue in the main proceedings is applicable without distinction, without consideration of the nationality of the parties concerned or even of the origin or destination of the goods, since it is binding on all undertakings established in the Dutch-speaking region of the Kingdom of Belgium. However, the absence of direct discrimination is not a sufficient criterion in itself, in the light of the Court’s case-law cited above, under which the conditions for implementing Article 35 TFEU may occasionally be fulfilled notwithstanding that finding. ( 44 ) In my opinion, in accordance with the criteria deriving from that case-law, a language regime such as that at issue in the main proceedings has a far greater effect on exports from the Member State concerned than on the marketing of goods in its domestic market.

60.

Practical problems arising here, in my opinion, have far greater impact in cross-border trade than in domestic trade because of the fact that the invoices must be drawn up in Dutch. The main drawback of not authorising another authentic version, thus having binding force, drawn up in a language freely chosen by the parties concerned, is that those parties are prevented from choosing a language of which they jointly have knowledge, and in particular a language more commonly used in international trade.

61.

The referring court rightly notes that recipients of such invoices will have difficulties in understanding them quickly, unless they are Dutch-speaking, which is, obviously, much less likely if the party concerned is established in another Member State ( 45 ) than if it is resident in Belgium, where Dutch is one of the official languages. ( 46 )

62.

The Belgian Government responds in this regard that a purchaser which does not understand an invoice drawn up in Dutch has the option either to request a translation from the outset or to challenge that invoice in cases of doubt. However, I take the view that the burden on an average purchaser of either of those approaches is likely to dissuade it either from concluding a contract with an undertaking established in the Flemish Region, if it manages to foresee that difficulty before signing the contract, or, at the very least, from trading with that undertaking again, if it becomes aware of that difficulty only once their transaction is ended.

63.

The Commission rightly points out that the sender of an invoice drafted in a required language may itself be more exposed, in those circumstances, to defaults on payments on account of the lack of actual or purported understanding which may be relied on by its foreign co-contracting party, as the Belgian Government indeed appears to acknowledge. Those specific circumstances arose in this case: the Italian company, potentially the debtor in respect of the contested invoices, relies on the Flemish language legislation, pursuing an approach which, to me, seems paradoxical ( 47 ) but still highly likely to lead to an outcome in its favour in the proceedings initiated by New Valmar.

64.

For its part, the Belgian Government maintains that the referring court was wrong to invoke the time lost and the expenses incurred in having the invoices translated from Dutch into a language understood by their recipient, on the grounds that this was almost certainly inevitable in international trade and that this burden would be placed on Flemish undertakings even if it was possible for them to draw up their invoices in the foreign language of their choice. However, this is not the case for exporters with internal resources enabling them to use directly, therefore without incurring any translation costs, a language of which they have specific knowledge. ( 48 ) By requiring the use of Dutch, the legislation concerned thus results in translation charges for those undertakings seeking to effect cross-border sales, which otherwise would not have been necessary.

65.

Even if it were established, as the Belgian Government claims, that the requirements arising from the legislation concerned do not require complete monolingualism but are confined to the mandatory details on VAT, any imposed bilingualism would, in any event, in itself constitute too great a material constraint, in my view, particularly so in the context of international trade. After all, the obligation to set out invoices, as required, in two languages, namely in Dutch for some mandatory details — according to information provided by the Belgian Government — and in another language chosen by the parties as regards the other details, constitutes a form of conduct that exporting Belgian undertakings find difficult to maintain in practice, especially where they export on a large scale and therefore issue large volumes of invoices to various foreign trading partners.

66.

As a result, that legislation produces a dissuasive effect with regard to intra-Community trade, not only for those undertakings established in the Flemish Region which seek to export their goods to other Member States, as alleged by New Valmar, but also for foreign companies seeking to conclude a transaction with those undertakings but which may be hampered by the uncertainty surrounding delivery, on account of the obligation to draw up the invoices in Dutch. I would add that significant legal uncertainty results from those national measures for the two parties also in view of the harsh penalties provided for therein, ( 49 ) uncertainty which, to my mind, is especially evident where the parties have chosen, as in the main proceedings, to apply the legislation of another Member State to their agreement.

67.

In challenging that analysis, the Belgian Government also argues that, even though the same language legislation is concerned, this case must be distinguished from that giving rise to the judgment in Las, ( 50 ) on the grounds that the main proceedings here are not directly connected with the conclusion of the agreement signed by the parties, since their subject matter is invoices and the legislation in question did not affect their freedom to choose the language in which they drew up their agreement.

68.

However, the referring court rightly states that the contested invoices are confirmation of accounts receivable from a previous contract ( 51 ) and that such legislation may prevent the contracting parties from understanding one another easily and correctly in the payment arrangements made in performance of their contract. Thus, in this instance there is a close relationship between those invoices and the implementation of the contract from which they derive. Furthermore, invoices themselves may also create legal obligations in addition to those arising from that contract. ( 52 ) Moreover, it is not unusual for trade relations to be established through the drawing up of an invoice, without any prior written contract. In those two sets of circumstances, the legislation at issue undeniably determines the language in which the exchange of consents occurs. Lastly, I would point out that despite the fact that the legislation is not intended to govern the drafting of the contracts themselves, it may actually have the effect, as I have already established, ( 53 ) of hampering the establishment or renewal of trade agreements with persons established in another Member State.

69.

Taking account of all those points, I submit that such national measures have a direct impact on intra-Community transactions. Therefore, this situation is not covered, in my view, by the Court’s case-law, under which national legislation is not in general declared contrary to EU law where ‘the restrictive effects which [that legislation] might have on the free movement of goods are too uncertain and too indirect to warrant the conclusion that it is liable to hinder trade between Member States’. ( 54 ) Here, I would mention, on the one hand, that the restrictive effect in point in these circumstances depends, not on a future and hypothetical event, but on the mere exercise of the right to freedom of movement for goods, and, on the other hand, that the scale of that effect in practice is irrelevant since any restriction, even minor, of that freedom is prohibited. ( 55 )

70.

Consequently, it seems to me that a language regime such as that at issue in the main proceedings, under which a specific official language must be used for the drafting of invoices by all undertakings established in one of the federal units of the Member State concerned, constitutes a measure having an effect equivalent to quantitative restrictions on exports for the purposes of Article 35 TFEU. It remains to be established whether such legislation may nonetheless be justified in the light of EU law. ( 56 )

71.

As the Court has consistently held, a national measure which restricts the exercise of one of the freedoms of movement laid down by the Treaty but which pursues a legitimate objective in the public interest may be declared to be compatible with EU law if, first, it is appropriate to ensuring the attainment of that objective and, secondly, it does not go beyond what is necessary to attain it. ( 57 )

72.

A national measure which, although applying without distinction as to the nationality of the parties concerned or the origin of the goods, is considered to be an obstacle to the free movement of goods may nonetheless be found to be in accordance with EU law, either because it is justified by one of the grounds of public interest contained in Article 36 TFEU and meets the requirements set out therein, ( 58 ) or because it meets overriding requirements in the public interest which have been acknowledged in the Court’s case-law while being appropriate for attaining the objective pursued and proportionate to that objective. ( 59 )

73.

As regards the first category of exceptions, even though the Commission proposes to include Article 36 TFEU in the answer to the question referred, none of the grounds of justification listed in that provision has been expressly cited, nor, moreover, do any of them seem to me to be particularly relevant in this case.

74.

Concerning the second category of exceptions, the Commission alone contemplates the possibility of taking consumer protection as the basis for legitimising restrictive measures such as those concerned in this case. ( 60 ) However, the Commission itself rightly takes the view that such an objective in the public interest cannot be relied upon in this case, as a ground capable of justifying a restriction on the free movement of goods, since the main proceedings are between two professional contracting parties, a relationship having no direct impact on consumers.

75.

Therefore, the question that arises primarily is whether and, where appropriate, to what extent the justifications recognised by the Court in the judgment in Las, ( 61 ) concerning the provisions of Flemish language legislation that applied at the material time to employment relations, can be extended to this case. In that judgment, the Court held that the three objectives to which the Belgian Government had recourse, namely to promote and encourage the use of one of the official languages of the Kingdom of Belgium, to secure the social protection of employees and to facilitate the related administrative controls, are included in the overriding reasons in the public interest capable of justifying a restriction on the exercise of the fundamental freedoms recognised in the Treaty.

76.

The first of those three grounds is also relied on in this case by the Belgian Government, which submits that the legislation concerned meets the need to safeguard the use of the official language of the Flemish Region. I can confirm that it is apparent from the case-law that promoting and encouraging the use of one or more official languages of a Member State constitutes a legitimate objective which, in principle, justifies a restriction on the obligations imposed by EU law. ( 62 ) This applies in particular to the prohibition of measures having an equivalent effect to quantitative restrictions on exports which is laid down in Article 35 TFEU. In view of the specific functions performed, in both the commercial and public spheres, by official documents such as invoices, ( 63 ) a measure such as that at issue in the main proceedings seems to me potentially capable of protecting the common use of such a language in those different areas, as the Lithuanian Government points out. ( 64 )

77.

Secondly. according to the Belgian Government, requiring that Dutch be used in drawing up those documents required by law guarantees the speed and effectiveness of the checks carried out by the competent VAT authorities. New Valmar rejects that line of argument, unlike the Lithuanian Government. I note that the Court has repeatedly held that the objective of facilitating and therefore of intensifying administrative and fiscal supervision may underpin restrictions on the fundamental freedoms enshrined in the Treaty. ( 65 ) Language legislation such as that referred to here is, in principle, capable of assisting the authorities responsible for conducting checks on company documents ( 66 ) and, accordingly, of guaranteeing compliance with the provisions of domestic law and EU law, especially in the area of indirect taxation. ( 67 )

78.

To my mind, the Belgian Government is right to invoke those two overriding reasons in the public interest as possible justification for the restriction on the free movement of goods that I consider to be established, but it still has to be ascertained whether legislation such as that at issue in the main proceedings, especially in the light of the penalties it imposes, is indeed proportionate to the objectives concerned. In my opinion, the proportionality criterion is not met in this case.

79.

The referring court is uncertain whether the negative answer given on account of a lack of proportionality in the judgment in Las, ( 68 ) which was concerned with the provisions of the language legislation at issue here applying to employment relations, can be transposed to this case, bearing in mind in particular that the rules on the penalties imposed in the event of infringement of that legislation, that is to say absolute nullity to be determined by the courts of their own motion, ( 69 ) are similar for the contested invoices.

80.

The Commission submits that the objections regarding the assessment of proportionality adopted in the judgment in Las ( 70 ) must be applied mutatis mutandis in this case. I shall make some observations on this matter, bearing in mind the differences established between the case which gave rise to that judgment and the present case.

81.

The first of the objections set out by the Court concerned the fact that the establishment of free and informed consent between the parties requires those parties to be able to draft their contract in a language other than the official language of that Member State where they do not have knowledge of that language. It is not clear whether that element of assessment is less important with regard to the main proceedings, which relate here not to the conclusion of a contract per se ( 71 ) but to the drafting of invoices, which are documents required by law and therefore not established exclusively by consent, even though they are an integral part of trade. However, I would point out that, irrespective of the fact that invoices ensure the performance of the initial contract, they can produce their own legal effects vis-à-vis the parties or serve themselves to aid the meeting of wills which forges the contractual relationship. ( 72 )

82.

The second of those objections alleged that the legislation at issue did not allow an authentic version of the cross-border employment contracts to be drawn up also in a language known by all the parties concerned. The decisive nature of that objection in this case also gave rise to a reservation inasmuch as the Belgian Government asserts, contrary to the decision to refer, that the mandatory use of Dutch is, in this instance, limited to the statutory information relating to VAT only and does not extend to all other information on the invoices, including details of a contractual nature. ( 73 ) It will, of course, fall to the referring court to establish whether this is the case under Belgian law, ( 74 ) but, in order to cater for that eventuality, I consider it necessary to give an answer to the question referred which takes into consideration the uncertainty accordingly prevailing with regard to the scale of the linguistic constraints imposed in these circumstances.

83.

Notwithstanding those considerations, I concur with New Valmar, the Lithuanian Government and the Commission that a language regime such as that at issue in the main proceedings does not meet the obligations under EU law inasmuch as it exceeds the measures strictly necessary to attain the public interest objectives mentioned above, ( 75 ) both in terms of the status conferred on the language concerned and in terms of the penalty imposed in the event of infringement of that legislation.

84.

It seems to me that the public interest objectives cited, namely those of promoting an official language and facilitating supervision, might just as easily be guaranteed by measures that are less detrimental to the free movement of goods than the requirement that a predetermined language must be used in company documents such as invoices, to the exclusion of any other official language of the Member States of the Union.

85.

I would point out that, assuming the accuracy of the Belgian Government’s claim that this obligation is confined to the statutory information relating to VAT, my position would be unchanged, for the practical reasons I have set out above ( 76 ) and for the reasons set out below.

86.

First of all, the fact must not be overlooked that the aims ( 77 ) of the obligation to issue invoices are not only to safeguard public interests, which justify, for example, the exercise of administrative or fiscal supervision by the competent national authorities, but also to protect private interests, in particular those of the purchaser which must be clearly informed as to the content of the delivery, two categories of interests which must be duly weighed in order to find a fair balance between them. Thus, where a law requires an invoice to be drafted in a given language, it is critical, in my view, for the recipient which has no knowledge of that language to have the possibility to benefit from another authentic version, so that it can understand more easily the details on that invoice ( 78 ) and therefore be assured that the vendor has met its contractual obligations.

87.

Considerations specific to transactions in international trade should also be included, in which respect it may be necessary to relax the statutory, in this instance linguistic, constraints so as not to hinder excessively cross-border trade. As observed by the Lithuanian Government and the Commission, there are specific problems in this area, such as those rightly described by New Valmar, ( 79 ) and commercial practices, ( 80 ) that should be taken into account as far as possible to promote that type of trade, in particular within the European Union. ( 81 ) These considerations are especially relevant as regards the particulars contained in invoices relating to freedom of contract, such as the general conditions of sale, but, in my opinion, it would also be helpful, if not indispensable, if mandatory particulars, such as those relating to VAT mentioned by the Belgian Government, could also be understood by all parties to the cross-border economic relationship.

88.

To my mind, language rules such as those at issue in the main proceedings go beyond what is strictly necessary to promote the use of Dutch and to enable the competent authorities to check the relevant details. It would, in my opinion, be sufficient in practice, where the parties concerned wish to draft invoices in another language, to require a translation into Dutch only of the statutory particulars or, as necessary, a subsequent translation if such a version is not submitted at the time checks are carried out.

89.

In this connection I would point out first of all that, as regards VAT, under the abovementioned provisions of Directive 2006/112 only the Member States of destination may demand a translation of certain invoices drafted in a foreign language, where that is necessary for control purposes. ( 82 )

90.

Furthermore, alternative approaches, deriving from other provisions applying also in Belgium, support that view. These are, on the one hand, equivalent, but not identical, provisions to those at issue here which have been adopted by the French Community of the Kingdom of Belgium, from which it follows that company documents such as invoices which are drawn up by persons established in the French-speaking region must in principle be drawn up in French, but ‘without prejudice to the complementary use of the language chosen by the parties’. ( 83 ) That possibility of additional recourse to a language other than the language of that region, a language which is chosen by the parties concerned and, therefore, of which they are all likely to have a better knowledge than of French, constitutes a less restrictive measure than that requiring the exclusive use of a specific language in the course of trade. ( 84 )

91.

On the other hand, in 2014 the Flemish Community itself amended the abovementioned Decree on the use of languages ( 85 ) with the result that its provisions on employment relations are less restrictive than they were at the material time in the case giving rise to the judgment in Las. ( 86 ) Article 5(1) of that decree still provides that the use of Dutch is the general rule in the Flemish Region, but Article 5(2) now allows, in respect of ‘individual employment contracts’, a ‘version having the force of law [to be drawn up] in one of the [official] languages [of the Member States of the European Union or of the European Economic Area (EEA)] understood by all the parties concerned’, on the condition that certain criteria governing connection with those territories are met. ( 87 )

92.

Language rules similar to either of those approaches, both of which are less intrusive on the free movement of goods than the legislation at issue in the main proceedings, while appropriate for guaranteeing the public interest objectives invoked by the Belgian Government, could, in my view, also be adopted in the circumstances of this case.

93.

Countering the claim that the language regime concerned lacks proportionality, the Belgian Government argues that the impact of the penalty imposed in the event of infringement, namely nullity to be declared by the courts of their own motion, is less significant in the case in point than in the case giving rise to the judgment in Las. ( 88 ) It asserts that, unlike the main proceedings in the latter case, in which the contract of employment which had not been drawn up in Dutch had to be annulled, in this case only the validity of the contested invoices can be affected, not the validity of the concession agreement binding the parties concerned. Since the invoices would merely confirm accounts receivable as a result of the agreement concluded between the parties, a declaration that they are null and void would not prevent recovery of those receivables and, moreover, it would be possible to substitute new, valid invoices for those which do not comply with the legislation.

94.

New Valmar contends that, even though the impact of the nullity is tempered by the option afforded to the vendor of drawing up substitute invoices during the proceedings, the beneficial effects of that tempering measure are, however, only theoretical. According to New Valmar, the fact that new invoices have to be sent to the debtor, and not Dutch copies of the original invoices, would have a number of adverse consequences. On the one hand, from a tax perspective, the VAT exemption established for intra-Community deliveries would not apply to the substitute invoices because that exemption is valid only when the goods leave the national territory, not on a deferred basis. On the other hand, from a civil-law perspective, default interest payable to the vendor on overdue invoices would not start to run until the date of substitution, while a debtor which did not challenge the original invoices in the period prescribed by the law would still have the option of lodging a complaint regarding the substitute invoices. ( 89 )

95.

In my view, the penalties laid down by the legislation at issue in the main proceedings are not indispensable for attaining the objectives in the public interest cited by the Belgian Government, since annulling invoices not drafted in Dutch does not contribute directly either to promoting that language or to facilitating actual administrative or fiscal supervision. Furthermore, these drastic penalties are, to my mind, clearly excessive.

96.

As the Lithuanian Government and the Commission have pointed out, absolute nullity, which entails the loss from the outset of the legal effects of such invoices and must be declared by the courts of their own motion, may be a source of considerable legal uncertainty for the two parties to the economic relationship concerned, which may be detrimental to cross-border trade, even though such trade is to be encouraged under EU law.

97.

This observation appears to me to be particularly true as regards the vendor. In view of the information at the Court’s disposal, it cannot be ruled out a priori that, because of the obligation to issue a substitute invoice in Dutch, the vendor will encounter not only VAT-related problems, or face the loss of default interest relating to the original invoice, but will also encounter limitation issues surrounding the issuing of the new invoice, as New Valmar claims. ( 90 ) Furthermore, undertakings which have remitted invoices in a language other than that required may be exposed, as is the case in the main proceedings, to an entirely opportunistic challenge on the validity of those documents recording their claims. ( 91 ) Moreover, the recipient of the unlawful invoices might also be penalised by this system of penalties, albeit to a lesser degree, in that the invoices annulled may lose all or part of their probative value. ( 92 )

98.

Even though it is for the referring court to assess whether those potentially negative consequences actually arise in these circumstances, in the light of the law applicable in the main proceedings, I submit, in any event, that the methods chosen in the language regime concerned are wholly excessive. After all, to attain the objectives pursued, it would, in my view, be possible to resort to less restrictive penalties on the free movement of goods.

99.

In the light of all those factors, I am of the opinion that Article 35 TFEU must be interpreted as precluding legislation of a federal unit of a Member State, such as that at issue in the main proceedings, which requires every undertaking which has its place of establishment within the territory of that unit to draw up invoices which are of a cross-border character, at least as regards some of their mandatory particulars if not in their entirety ( 93 ), exclusively in the official language of that federal unit, failing which they will be declared null and void by the courts of their own motion.

100.

In the light of the foregoing considerations, I propose that the Court should answer the question referred by the Rechtbank van Koophandel te Gent (Commercial Court, Ghent, Belgium) as follows:

Article 35 TFEU must be interpreted as precluding legislation of a federal unit of a Member State, such as that at issue in the main proceedings, which requires every undertaking which has its place of establishment within the territory of that unit to draw up invoices which are of a cross-border character — if only for some of their mandatory particulars — exclusively in the official language of that federal unit, failing which they will be declared null and void by the courts of their own motion.