The Société des produits de maïs SA, the plaintiff in the main proceedings, imports, exports, buys, processes and sells maize and various maize products.

It exported from France to other Member States of the European Economic Community various processed maize products, that is to say:

Monetary compensatory amounts were charged on those exports under Commission Regulation No 562/76 of 24 March 1976 (Official Journal 1976 L 79, p. 4), as amended by subsequent regulations.

Since Regulation No 652/76 and the subsequent regulations amending it were held to be invalid by the Court of Justice in its judgment of 15 October 1980 (Case 145/79 Roquette [1980] ECR 2917), the Société des produits de maïs, by a document dated 30 December 1980, brought an action against the Administration des Douanes et Droits Indirects before the Tribunal d'instance, Paris (First Arrondissement), for the reimbursement of the improperly levied monetary compensatory amounts on the ground that they had no basis in law. Those amounts are as follows:

together with interest thereon at the legal rate.

In its defence the Administration des Douanes contended, on the one hand, that the plaintiff had not shown that the compensatory amounts fixed by the regulation in question in respect of the derived products clearly exceeded the amounts fixed in respect of the quantity of maize used in the manufacture of those derived products, and, on the other hand, that the Court had decided in the aforementioned judgment of 15 October 1980 that the fact that Regulation No 652/76 and the subsequent regulations amending it are invalid does not enable the charging or payment of monetary compensatory amounts by the national authorities on the basis of those provisions to be challenged as regards the period prior to the date of the judgment.

The Tribunal d'instance considered that by deciding in its judgment that there could be no reimbursement of sums charged prior to the date of the judgment, the Court largely deprived its declaration of invalidity of its relevance, that the judgment was completely contrary to the Court's previous case-law and finally that it raised important questions with regard to the application of Article 177 and the second paragraph of Article 174 of the EEC Treaty. It therefore decided, by judgment of 7 June 1983, in the interests of efficient administration of justice and of clarity, to stay the proceedings and refer the following questions to the Court of Justice for a preliminary ruling:

The order making the reference was registered at the Court Registry on 16 June 1983.

In accordance with Article 20 of the Protocol on the Statute of the Court of Justice of the EEC, written observations were submitted by the Commission of the European Communities, represented by its Legal Adviser, F. Lamoureux, and by the Société des produits de maïs, represented by A. Desmazières des Sechelles of the Paris Bar.

Upon hearing the report of the Judge-Rapporteur and the views of the Advocate General, the Court decided to open the oral procedure without any preparatory inquiry. Nevertheless the Court requested both the Commission and the plaintiff in the main proceedings to reply in writing to a number of questions.

The Commission, whilst emphasizing that the documents forwarded to the Court did not indicate when the exports at issue had taken place, considers it necessary to point out that, apart from maize starch (tariff subheading 11.08 A I), the products to which the main proceedings relate are different from those concerned in Case 145/79 and that in the judgment making the reference the national court referred, in the case of some products, to general tariff headings of the Common Customs Tariff and not to specific subheadings, whereas the contested regulations fixed monetary compensatory amounts for products falling within certain subheadings and not within general headings. In addition the Commission considers that there were a number of errors and a certain amount of confusion in the judgment making the reference: subheading 17.02-23 does not cover any product either in the Common Customs Tariff or in the Nomenclature of Goods for External Trade Statistics of the Community and Statistics of Trade between States (hereinafter referred to as Nimexe); subheading 17.02-28.0 and 17.02-28.1 are Nimexe codes which correspond to subheading 17.02 B II (b) of the Common Customs Tariff; finally heading 29.04-77.001 is a Nimexe code corresponding to subheading 29.01 C III (b) 1 of the Common Customs Tariff.

Considering in turn the products in question, it states that broken maize and gluten both fall within subheading 23.02 A I (bran of maize or rice). With regard to the other maize products subheading 11.08 A I covers maize starch, subheadings 17.02 B I (A) I, 17.02 B I (b), 17.02 B II (a) and 17.02 B II (b) glucose and glucose syrup, subheading 35.05 A dextrins and subheading 29.04 C III (b) 1 (corresponding to Nimexe code 29.04-77.001) glucitol (sorbitol).

With regard to the first question the Commission recalls that in the aforementioned Case 145/79 the Court of Justice declared Regulation No 652/76 invalid in particular on the ground that the Commission had exceeded the limits placed upon it by Regulation No 974/71 by fixing compensatory amounts applicable to maize starch on the basis of the intervention price of maize without deducting the production refund, when the compensatory amounts on other products processed from maize in respect of which no production refund was provided for were also calculated on the basis of the intervention price of maize. The Commission drew the appropriate inference from that judgment and, with effect from the date thereof, amended the monetary compensatory amounts applicable to products in respect of which it had not taken into account the amount of the production refund by adopting Regulation No 3013/80 of 21 November 1980 (Official Journal 1980 L 312, p. 12) as regards the products covered by the common organization of the market in the cereals sector and Regulation No 3224/80 of 11 December 1980 (Official Journal 1980 L 340, p. 1) as regards certain processed agricultural products not covered by Annex II to the Treaty. It emphasizes that new compensatory amounts were fixed in respect of all the products in question, except for those falling within subheading 23.02 A I, because it took the view that the ground on which the Court declared invalid the fixing of the compensatory amounts applicable to maize starch extended to a series of products in respect of which the amounts were fixed on a basis other than that of the intervention price of maize after deduction of the production refund. It should therefore be declared, in reply to the first question, that, with regard to the fixing of the monetary compensatory amounts applicable to the products falling within subheadings 11.08 A I, 17.02 B I, 17.02 B II, 23.03 A I, 29.04 C III (b) 1 and 35.05 A, Regulation No 652/76 is invalid for the reasons given in the judgment of 15 October 1980.

With regard to products falling within subheading 23.02 A I (broken maize and gluten), the Commission recalls that in Case 145/79 the Court decided that Regulation No 652/76 might also be invalid in so far as the sum of the monetary compensatory amounts applicable to products obtained by processing a given quantity of a basic product in a specific manufacturing process was clearly in excess of the monetary compensatory amount fixed for that given quantity of the basic product. It observes, however, that the plaintiff in the main proceedings does not specify the type of manufacturing process in which the quantities of bran at issue were obtained according to the type and quality of the main products sought and, in addition, fails to demonstrate that the sum of the monetary compensatory amounts applicable to the derived products, including bran, was clearly in excess of the compensatory amount applicable to the quantity of maize from which those products were obtained.

It follows, according to the Commission, that the Court should also state, in reply to the first question, that consideration of the question referred to it has disclosed no factor of such a kind as to affect the validity of Regulation No 652/76 with regard to the fixing of the monetary compensatory amounts applicable to the products falling within tariff subheading 23.02 A I.

With regard to the second, third and fourth questions, the Commission notes that the Court has already declared in its judgment of 15 October 1980 that the fact that the provisions are invalid does not enable the charging or payment of monetary compensatory amounts by the national authorities on the basis of those provisions to be challenged as regards the period prior to the date of the judgment. In those circumstances it takes the view that, in the light of the grounds of the judgment making the reference, what is at issue is not so much the problem of the applicability of the Court's answer to all similar cases as the question whether an analogous application of the second paragraph of Article 174 in the context of a preliminary ruling declaring a measure to be invalid is well founded.

In that respect it recalls that the Tribunal d'instance, Lille, the court a quo in Case 145/79, objected to the limits placed by the Court of Justice upon the invalidity of Regulation No 652/76 and argued in its judgment of 15 July 1981, with regard to the analogous application of the second paragraph of Article 174, that after it had interpreted Community law for the purpose of replying to questions referred to it for a preliminary ruling and had exhausted its powers, the Court took the step, for which there was no basis in law, of adding to the opinion it had thereby given a comment based on a provision which was not applicable to the situation under consideration. Far from amounting to a complementary statement which assisted it in its task of interpretation, the step taken by the Court constitutes the deliberate expression of a choice whereby preference is given to the principle of legal certainty over that of legality and to the authority of the Community legal order over the national legal order. According to the Commission the questions contained in the judgment making the reference have the merit of making it possible to debate before the Court the question of an analogous application of the second paragraph of Article 174, which had not been possible in Case 145/79 since the question had not been raised by the Commission until the hearing.

The Commission notes that it had on many occasions asked the Court to apply the second paragraph of Article 174 and considers it sufficient, on the one hand, to recall the general reasons which justify the position adopted by the Court in the context of a judgment declaring a measure to be invalid and, on the other hand, to stress that the limitation of the effects of a declaration of invalidity must, in principle, be without prejudice to claims submitted to the national authorities before the date of the Court's judgment.

With regard to the justification of the application by analogy of the second paragraph of Article 174 in judgments declaring legislation to be invalid, the Commission is of the opinion that such application meets a twofold need: to ensure that Community law is applied uniformly and to safeguard legal certainty. In that respect it emphasizes that it is consistent with the aims of Article 177 to recognize that preliminary rulings on the interpretation of the Treaty or the validity of acts of the institutions have general effects, or at least effects extending beyond the case in question, since Article 177 is intended to guarantee the uniform application of Community law by national courts. With regard to judgments declaring a measure to be invalid, as the Court has stated in its judgment of 13 April 1981 in Case 66/80 (International Chemical Corporation [1981] ECR 1191), there are particularly imperative requirements concerning legal certainty in addition to those concerning the uniform application of Community law.

The idea that preliminary rulings extend beyond the context of the main proceedings in question involves the recognition that they have effect ex tunc. That solution, adopted with regard to the effect of interpretative judgments, has also been applied to judgments declaring a measure to be invalid. The attribution of effect ex tunc to declarations of invalidity, whilst it assimilates judgments declaring a measure to be void still closer to judgments declaring a measure invalid, may involve serious and sometimes unforeseeable consequences in relation to the past by calling into question again legal relationships which have been settled, especially in a Member State whose legislation provides for lengthy limitation periods.

The upsetting of established legal relationships as a result of a judgment declaring a measure invalid may be the exact counterpart of the effect of a judgment declaring a measure to be void and in those circumstances there is no reason why the court should not, if need be, limit the retroactive effect of its decision, just as it may do when it declares a measure to be void.

By inserting the second paragraph of Article 174 in the Treaty its authors, reflecting the position which exists in most legal systems, acknowledged that in exceptional cases the conflict inherent in every legal system between legal certainty and equity may be resolved by protecting relationships formed under the law as it previously stood, even if it was invalid. Article 174 therefore operates as a safety valve. In fact, according to the Commission, such a solution extends beyond the strict confines of proceedings for a declaration that a measure is void and must guide the Court whenever it is faced with the possibility that difficulties, sometimes inextricable, may arise from the fact that, as regards the past, a legal situation is called into question again.

The Commission emphasizes that the general grounds of legal certainty on which the second paragraph of Article 174 is based have already led the Court to hold, in its judgment of 8 April 1976 in Case 43/75 (Defienne II [1976] ECR 455), that the direct effect of Article 119 cannot be relied on in order to support claims concerning periods prior to the date of the judgment. The Court adopted the same approach in the Roquette case. In the Defienne II case the Court emphasized that although the practical consequences of any judicial decision must be carefully taken into account, it would be impossible to go so far as to diminish the objectivity of the law and compromise its future application on the ground of the possible repercussions which might result, as regards the past, from such a judicial decision.

The fact that the Treaty has not expressly provided for the possibility of restricting in time the effects of judgments declaring a measure invalid cannot be relied upon as a ground for concluding that in the Roquette case the Court exceeded its jurisdiction and substituted itself for the legislature. Such an analysis, quite apart from excluding the possibility of the Court's filling a gap in the Treaty in accordance with the system of Community law, in fact challenges the whole sytem of legal protection against unlawful measures adopted by the legislature, a system to which the mechanism of cooperation between the Court of Justice and national courts provided for by Article 177 is geared.

Finally the Commission considers that the criticism in French academic writing of the application by analogy of the second paragraph of Article 174 is based, in fact, on a confusion between, on the one hand, the aims of the objection of illegality as structured in French law for the purpose of ensuring strict separation of the areas of jurisdiction of the various hierarchies of courts and, on the other hand, the aims of Article 177 which envisages, not the separation of areas of jurisdiction, but cooperation in order to ensure that Community law is applied uniformly.

The solution adopted by the Court in the Defrenne II case and expressed in German law in the final sentence of paragraph 79 (2) of the Gesetz über das Bundesverfassungsgericht [Law concerning the Federal Constitutional court] and in Paragraph 183 of the Verwaltungsgerichtsordnung [code of procedure before the administrative courts], whereby an application by analogy of the second paragraph of Article 174 must protect the special position of those who have challenged the legality of the invalidated regulation prior to the date of the judgment declaring it invalid, is justified, in the Commission's opinion, by the need to ensure effective legal protection for individuals who have initiated contentious proceedings in good time.

Nevertheless the Commission accepts that there may be limits to the extent to which that exception, namely the case of claims brought prior to the judgment declaring the regulation invalid, to the application by analogy of the second paragraph of Article 174 may be taken into account. Such is the case where the restriction in time of the effects of a judgment does not impose any real burden on the persons concerned or where the court states, as it did in its judgments of 15 October 1980, that the recovery of sums paid but not owed would be capable of causing considerable differences in treatment, thereby causing further distortions in competition.

On the basis of the foregoing observations the Commission proposes that the Court should reply to the second, third and fourth questions in the following manner:

The Société des produits de maïs, the plaintiff in the main proceedings, considers that the first two questions referred to the Court call for little comment, since the Court, in its judgment of 15 October 1980, declared that Regulation No 652/76 and the subsequent regulations were invalid:

According to the plaintiff in the main proceedings the solution arrived at in that judgment also applies to the products referred to by it in its application for the reimbursement of monies paid but not owing.

In that respect it notes first that the products obtained by processing maize are virtually standard products, the manufacture of which requires a quantity of maize which is virtually the same from one manufacturer to another, which explains why the Commission fixes the prices and compensatory amounts applicable to derived products by reference to the prices and compensatory amounts applicable to the basic products. It goes on to state that, like any other exporter of maize products, it is able to show, on the one hand, that the compensatory amounts charged in respect of exports of maize starch and maize glucose were fixed on a basis other than that of the intervention price of maize after deduction of the production refund on starch and, on the other hand, that the compensatory amounts charged in respect of its exports of dextrose and modified products were fixed at a figure appreciably higher than the compensatory amount fixed for the quantity of maize from which they were processed. Finally, although no express reference was made to this point in the Roquette judgment, the rule that compensatory amounts applicable to products obtained by the processing of a given quantity of maize cannot be higher than the amount fixed for that given quantity should also apply to exports of gluten (heading No 23.03) and broken maize (heading No 10.03, now 23.02).

In that respect it emphasizes that gluten and broken maize are products derived from processing maize, that is to say they are secondary products obtained in the course of manufacturing starch, glucose, dextrose, or modified products, and that since a compensatory amount is charged on the primary product it follows that if an amount is also charged on the secondary product the total compensatory amount will, by definition, clearly exceed the compensatory amount charged on the basic product which has been utilized.

Consequently, it considers that the answer to be given to the national court should confirm the invalidity of Regulation No 652/76 as declared in the judgment of 15 October 1980 whilst stating that the said regulation, and the subsequent regulations amending it, are also invalid:

With regard to the last two questions the plaintiff in the main proceedings, like the Commission, considers that, notwithstanding the third paragraph of the operative part of the judgment in the Roquette case, it would be useful for the thorny problem of the effect in time of judgments in proceedings for a preliminary ruling on validity to be debated before the Court.

In that respect it emphasizes that the solution adopted by the Court in that judgment has been the subject of sharp criticism in academic legal writing (Dalloz 1981, Jurisprudence p. 168, note signed Y.L.; Dalloz 1982, Jurisprudence p. 10, note by Boulouis; Joliet, Le Droit Institutionnel des Communautés Européennes — Le Contentieux, p. 233; Labayle, in Revue Trimestrielle du Droit Européen 1982, p. 484 and Actualité Juridique du Droit Administratif 1983, p. 168) and has been resisted to a considerable extent by French courts (Tribunal d'instance, Lille, 15 July 1981, Dalloz 1982, Jurisprudence p. 9; Tribunal d'instance, Douai, 19 January 1983, Gazette du Palais, 1 June 1983, Jurisprudence p. 3).

According to the plaintiff in the main proceedings it is desirable that the Court should revise its position and return to its previous case-law (in particular its judgment of 12 June 1980 in Case 130/79 Express Dairy Foods Limited [1980] ECR 1887, following the proposals in the Opinion of Mr Advocate General Capotorti).

The second paragraph of Article 174 of the EEC Treaty should not be applied by analogy in the context of proceedings under Article 177 of the Treaty. Once it has been declared invalid in a preliminary ruling, a regulation can be nothing else but null and void both as regards the parties and as regards the national court which referred the question to the Court of Justice for a preliminary ruling.

According to the plaintiff in the main proceedings that view is justified by the following considerations :

The plaintiff in the main proceedings, Société des produits de maïs SA, represented by A. Desmazières de Séchelles, and the Commission of the European Communities, represented by F. Lamoureux, acting as Agent, presented oral argument at the sitting on 11 July 1984.

The Advocate General delivered his opinion at the sitting on 14 November 1984.