CJEC, gr. chamber, September 19, 2006, No C-356/04

THE COURT (Grand Chamber)

1 This reference for a preliminary ruling relates to the interpretation of Article 3a(1)(a), (b) and (c) of Council Directive 84-450-EEC of 10 September 1984 concerning misleading and comparative advertising (OJ 1984 L 250, p. 17), as amended by Directive 97-55-EC of the European Parliament and of the Council of 6 October 1997 (OJ 1997 L 290, p. 18) ('the Directive').

Legal context

2 Article 1 of the Directive states:

'The purpose of this Directive is to protect consumers, persons carrying on a trade or business or practising a craft or profession and the interests of the public in general against misleading advertising and the unfair consequences thereof and to lay down the conditions under which comparative advertising is permitted.'

3 As provided in Article 2(2) of the Directive, 'misleading advertising' means:

'any advertising which in any way, including its presentation, deceives or is likely to deceive the persons to whom it is addressed or whom it reaches and which, by reason of its deceptive nature, is likely to affect their economic behaviour or which, for those reasons, injures or is likely to injure a competitor'.

4 Article 2(2a) of the Directive defines comparative advertising as:

'any advertising which explicitly or by implication identifies a competitor or goods or services offered by a competitor'.

5 Article 3 of the Directive states:

'In determining whether advertising is misleading, account shall be taken of all its features, and in particular of any information it contains concerning:

(a) the characteristics of goods or services, such as their availability, nature, execution, composition, method and date of manufacture or provision, fitness for purpose, uses, quantity, specification, geographical or commercial origin or the results to be expected from their use, or the results and material features of tests or checks carried out on the goods or services;

(b) the price or the manner in which the price is calculated, and the conditions on which the goods are supplied or the services provided;

(c) the nature, attributes and rights of the advertiser, such as his identity and assets, his qualifications and ownership of industrial, commercial or intellectual property rights or his awards and distinctions.'

6 Article 3a(1) of the Directive provides:

'Comparative advertising shall, as far as the comparison is concerned, be permitted when the following conditions are met:

(a) it is not misleading according to Articles 2(2), 3 ...;

(b) it compares goods or services meeting the same needs or intended for the same purpose;

(c) it objectively compares one or more material, relevant, verifiable and representative features of those goods and services, which may include price;

...'

7 Article 4(1) of the Directive states:

'Member States shall ensure that adequate and effective means exist to combat misleading advertising and for the compliance with the provisions on comparative advertising in the interests of consumers as well as competitors and the general public.

...'

8 Article 6 of the Directive states:

'Member States shall confer upon the courts or administrative authorities powers enabling them in the civil or administrative proceedings provided for in Article 4:

(a) to require the advertiser to furnish evidence as to the accuracy of factual claims in advertising if, taking into account the legitimate interest of the advertiser and any other party to the proceedings, such a requirement appears appropriate on the basis of the circumstances of the particular case and in the case of comparative advertising to require the advertiser to furnish such evidence in a short period of time; and

(b) to consider factual claims as inaccurate if the evidence demanded in accordance with (a) is not furnished or is deemed insufficient by the court or administrative authority.'

The main proceedings and the questions referred for a preliminary ruling

9 Lidl Belgium GmbH & Co KG ('Lidl') and Etablissementen Franz Colruyt NV ('Colruyt') each operate in Belgium a chain of stores which essentially retail basic consumables, under the names Lidl and Colruyt respectively.

10 On 19 January 2004, Colruyt sent its customers a mailshot ('the letter at issue') worded as follows:

'...

Last year, 2003, you were able once again to make significant savings with Colruyt.

On the basis of our average price index for the past year we have calculated that a family spending EUR 100 each week in Colruyt stores:

- saved between EUR 366 and EUR 1 129 by shopping at Colruyt's rather than at any other supermarket (such as Carrefour, Cora, Delhaize, etc.);

- and saved between EUR 155 and EUR 293 by shopping at Colruyt's instead of a hard discounter or wholesaler (Aldi, Lidl, Makro).

On the reverse side you will see the evolution of the price differential vis-à-vis other stores in the course of 2003. The figures indicate that the price differential between Colruyt and the other stores has increased even further over the last few months.

In order to be able to continue to guarantee the lowest prices, we compare daily 18 000 prices in other stores. In addition, we also collect all promotions. Our data are thus very much up-to-date. We store all the prices in our central computer.

Each month we use those prices to calculate the price differential between Colruyt and the other stores. We refer to this as our price index which is certified by Quality Control (Instituut voor Kwaliteitscontrole), an independent body.

The result: at Colruyt's you enjoy, every day and at any time of the year, the lowest prices. In 2004 also we remain true to this guarantee.'

11 The reverse side of the letter at issue features two charts. The first sets out the price differential between Colruyt and its competitors as at 22 December 2003, a differential which is stated to have been calculated by it on the basis of a daily comparison of the prices, including promotional prices, of comparable products sold in each Colruyt store and in the competing stores located in the region. The second illustrates the development of that differential over the whole of 2003.

12 In addition, the following text appears on the checkout receipts issued at stores operated by Colruyt:

'How much did you save in 2003?

If you spent EUR 100 at Colruyt's each week, then, according to our price index, you will have saved:

- between EUR 366 and EUR 1 129 in comparison with another supermarket (such as Carrefour, Cora, Delhaize, etc.);

- between EUR 155 and EUR 293 in comparison with a hard discounter or wholesaler (Aldi, Lidl, Makro).'

13 Both the letter at issue and the checkout receipts also refer to Colruyt's website where further explanation can be found of the system of price comparison applied by it and the method of calculating the price index.

14 In addition, some of Colruyt's advertising leaflets and checkout receipts contain the following statement regarding a selection of basic consumables sold in Colruyt stores, recognisable by their red labelling on which the word 'BASIC' appears:

'BASIC: Absolutely the lowest prices in Belgium.

Even cheaper than the comparable selection of the hard discounters (Aldi, Lidl) and the "Eerste prijs/1er prix" products of other supermarkets (such as Carrefour, Cora, etc.).

You will recognise the BASIC products by their red labelling and the word BASIC.'

15 Certain advertising leaflets also contain the following wording:

'BASIC = Absolutely rock-bottom prices:

In addition to a significant overall price reduction we can offer you from now on a large number of products that you can compare with those of the typical hard discounters (like Aldi and Lidl) and with the "Eerste prijs/1er prix" products of other supermarkets. These are our BASIC products: everyday basic products at absolutely rock-bottom prices.'

16 Lidl brought proceedings before the Rechtbank van Koophandel te Brussel (Brussels Commercial Court) for an order requiring the cessation of those various advertising practices which it considers to be contrary to Article 23a of the Belgian Law of 14 July 1991 on commercial practices and consumer information and protection as amended by the Law of 25 May 1999 (Moniteur belge/Belgisch Staatsblad of 23 June 1999, p. 23670). That provision transposed Article 3a of the Directive into national law.

17 In Lidl's submission, the advertising at issue is not objective, not verifiable and misleading. As regards, first, the advertising relating to the general level of prices, that advertising does not specify the products being compared, the number of them or their prices. Moreover, the general price level, calculated on the basis of a select sample of products sold by Colruyt, is extended by extrapolation to that advertiser's entire product range. Finally, the advertising does not differentiate individually between the advertiser's various competitors by a specific reference to the general price level of each of them, but refers to them in groups, placing them imprecisely within a range of price levels. As regards, second, 'BASIC' products, the advertising at issue identifies neither the products being compared nor their prices.

18 It was in those circumstances that the Rechtbank van Koophandel te Brussel decided to stay proceedings and refer the following questions to the Court for a preliminary ruling:

'(1) Must Article 3a(1)(a) of [the] Directive ... be construed as meaning that the comparison of the general price level of advertisers with that of competitors, in which an extrapolation is made on the basis of a comparison of the prices of a sample of products, is impermissible inasmuch as this creates in any event the impression that the advertiser is cheaper over its entire range of products, whereas the comparison made relates only to a limited sample of products, unless the advertisement makes it possible to establish which and how many products of the advertiser, on the one hand, and of the competitors used in the comparison, on the other, have been compared, and makes it possible to ascertain where each competitor concerned by the comparison is positioned in the comparison and what its prices might be in comparison with those of the advertiser and of the other competitors used in the comparison?

(2) Must Article 3a(1)(b) of [the] Directive ... be construed as meaning that comparative advertising is allowed only if the comparison relates to individual goods or services that meet the same needs or are intended for the same purpose, to the exclusion of product selections, even if those selections, on the whole and not necessarily in regard to every component, meet the same needs or are intended for the same purpose?

(3) Must Article 3a(1)(c) of [the] Directive ... be construed as meaning that comparative advertising in which a comparison of the prices of products, or of the general price level, of competitors is made will be objective only if it lists the products and prices being compared of the advertiser and of all the competitors in the comparison and makes it possible to ascertain the prices being charged by the advertiser and its competitors, in which case all products used in the comparison must be expressly indicated for each individual supplier?

(4) Must Article 3a(1)(c) of [the] Directive ... be construed as meaning that a feature in comparative advertising will satisfy the requirement of verifiability in that article only if that feature can be verified as to its accuracy by those to whom the advertising is addressed, or is it sufficient if the feature can be verified by third parties to whom the advertising is not addressed?

(5) Must Article 3a(1)(c) of [the] Directive ... be construed as meaning that the price of products and the general price level of competitors are in themselves verifiable features?'

Consideration of the questions

Preliminary observations

19 It should be noted at the outset, first, that two separate methods of comparative advertising are at issue in the main proceedings.

20 The first method involves comparing the general level of the prices charged by competing chains of stores in respect of their ranges of comparable products and inferring therefrom the amount that consumers can save on an annual basis depending on whether they purchase their basic consumables each day from one rather than another of those chains ('the first method of comparison at issue'). Those general price levels are determined monthly, then annually, on the basis of a daily record of the individual prices of a very wide sample of basic consumables, whether identical (branded products) or similar (unbranded products or the chain's own brand), sold by both the advertiser and each of its competitors. In order to determine the general price levels, the individual prices thus recorded are weighted according to the quantities of each product that are purchased from the advertiser.

21 The second method of advertising is based on the assertion that all of the advertiser's products that have a red label bearing the word 'BASIC' are sold by it at the lowest price in Belgium ('the second method of comparison at issue'). This selection of products consists of, first, branded products and, second, products sold unbranded or under the advertiser's own brand name. The price comparison relates, in the case of the first category, exclusively to identical branded products sold by both the advertiser and its competitor and, in the case of the second category, to products of comparable quality sold by the advertiser and its competitor.

22 The second preliminary point to note is that, given the objectives of the Directive and in particular the fact that, as the second recital in the preamble to Directive 97-55 points out, comparative advertising helps to demonstrate objectively the merits of the various comparable products and thus stimulate competition between suppliers of goods and services to the consumer's advantage, it is settled case-law that the conditions required of comparative advertising must be interpreted in the sense most favourable to it (Case C-112-99 Toshiba Europe [2001] ECR I-7945, paragraphs 36 and 37, and Case C-44-01 Pippig Augenoptik [2003] ECR I-3095, paragraph 42; see also Case C-59-05 Siemens [2006] ECR I-0000, paragraphs 22 to 24).

Order in which the questions are to be examined

23 Since the first question relates in a more specific way to the concept of misleading advertising and is asked exclusively in relation to the first method of comparison at issue, it is justified to deal first with the other four questions which, in a more general manner, relate to the other conditions under which comparative advertising is permitted and concern each of the methods of comparison at issue.

Question 2

24 By its second question, the referring court essentially seeks to ascertain whether Article 3a(1)(b) of the Directive must be interpreted as meaning that comparative advertising relating collectively to selections of basic consumables sold by two competing chains of stores rather than to individual products sold by them is capable of satisfying the condition, laid down by that provision, that it must 'compare goods or services meeting the same needs or intended for the same purpose'.

25 As is apparent from the second recital in the preamble to Directive 97-55, the harmonisation by the directive of the conditions governing the use of comparative advertising is to help to demonstrate objectively the merits of the 'various comparable products'. As stated in the ninth recital in its preamble, this requirement that the products be comparable is intended in particular to prevent comparative advertising from being used in an anti-competitive and unfair manner.

26 Article 3a(1)(b) of the Directive sets out that requirement, laying down that, if comparative advertising is to be permitted, the competing goods being compared must meet the same needs or be intended for the same purpose, that is to say they must display a sufficient degree of interchangeability for consumers.

27 It is true, therefore, that in order to satisfy the condition laid down by that provision, all comparative advertising must, in the interests of both consumers and competitors, rest in the final analysis on the comparison of pairs of products satisfying that requirement of interchangeability.

28 On the other hand, Article 3a(1)(b) of the Directive cannot be interpreted as meaning that every comparative advertisement must refer exclusively to such pairs of comparable products, viewed separately, and cannot relate collectively to two sets of such comparable products.

29 The Court has previously pointed out that the choice as to the number of comparisons which the advertiser wishes to make between the products which he is offering and those offered by his competitors falls within the exercise of his economic freedom (Pippig Augenoptik, paragraph 81).

30 Nothing permits the view immediately to be taken that such freedom does not also extend to the ability to make a comparison relating to the whole or part of the comparable product ranges sold by an advertiser and his competitor.

31 First, the wording of Article 3a(1)(b) of the Directive in no way dictates such an interpretation.

32 Second, as recalled in paragraph 22 of the present judgment, the conditions required of comparative advertising must be interpreted in the sense most favourable to it.

33 Having regard, in particular, to the fact that comparative advertising helps to stimulate competition between suppliers of goods and services to the consumer's advantage, the benefit of such advertising to consumers must thus necessarily be taken into account in assessing the requirement of comparability laid down by Article 3a(1)(b) of the Directive (see, to similar effect in relation to Article 3a(1)(g) of the Directive, Siemens, paragraphs 23 and 24).

34 In this regard it must be accepted, as the Advocate General has observed in points 35 and 36 of his Opinion, that the possibility of making a collective comparison relating to a selection of comparable products allows the advertiser to provide consumers with advertising information containing global and summarised data that may prove particularly useful to them.

35 That is especially true in a sector such as the mass distribution sector in which consumers usually make multiple purchases designed to meet their everyday needs. From the viewpoint of such purchases, comparative information relating to the general level of the prices charged by chains of stores or to the level of the prices charged by them in respect of a given selection of products which they sell is liable to prove more useful to consumers than comparative information limited to the prices of some particular product or other. That is indeed the reason why consumer-protection associations regularly carry out surveys of the general price levels of such stores.

36 Accordingly, in so far as the selections of products of two competitors to which the comparison relates each consist of products which, when viewed individually, satisfy the requirement of comparability laid down by Article 3a(1)(b) of the Directive, a matter which is for the referring court to establish, such selections can themselves be regarded as meeting that requirement.

37 That may be so in particular in the case of selections composed of comparable products sold by two competing chains of stores where it is asserted that the products comprising the advertiser's selection have the common feature of being cheaper than the - comparable - products comprising his competitor's. Such pairs of comparable products do not cease to meet the same needs or to be intended for the same purpose simply because they are compared collectively from the point of view of that common comparative feature.

38 The requirement laid down by Article 3a(1)(b) of the Directive may also be satisfied when a comparison is made of the general price level of all the comparable basic consumables sold by two competing chains of stores with a view to inferring therefrom the amount liable to be saved by consumers who make their purchases of such goods from one rather than the other of those chains. In such a situation, both the pairs of comparable products sold by those competing chains and the whole formed by those comparable products when they are acquired together in the context of the purchase of basic consumables are capable of satisfying the condition that they meet the same needs or are intended for the same purpose.

39 Having regard to all of the foregoing, the answer to the second question should be that the condition under which comparative advertising is permissible that is laid down by Article 3a(1)(b) of the Directive must be interpreted as not precluding comparative advertising from relating collectively to selections of basic consumables sold by two competing chains of stores in so far as those selections each consist of individual products which, when viewed in pairs, individually satisfy the requirement of comparability laid down by that provision.

Question 3

40 By its third question, the referring court seeks to ascertain whether Article 3a(1)(c) of the Directive must be interpreted as meaning that the requirement, laid down by that provision, that the advertising 'objectively compares' the features of the goods concerned signifies, in the event of comparison of the prices of a selection of basic consumables sold by chains of stores or of the general level of the prices charged by them in respect of the range of comparable products which they sell, that all the products and prices compared, that is to say both those of the advertiser and those of all of his competitors involved in the comparison, must be expressly listed in the advertisement.

41 As is apparent from the second recital in the preamble to Directive 97-55, the harmonisation by that directive of the conditions governing the use of comparative advertising is, in particular, to help to demonstrate 'objectively' the merits of the various comparable products.

42 The seventh recital in the preamble to Directive 97-55 states that the conditions for permitted advertising should include criteria of objective comparison of the features of goods and services.

43 Read in the light of those two recitals, Article 3a(1)(c) of the Directive must be interpreted as laying down two types of requirement relating to the objectivity of the comparison.

44 First, and as appears from the seventh recital in the preamble to Directive 97-55, the cumulative criteria requiring the product's feature in respect of which the comparison is made to be material, relevant, verifiable and representative, as laid down by that provision, help to ensure that the comparison is objective. However, the third question referred for a preliminary ruling does not directly concern those criteria; the criterion of verifiability is covered in the fourth and fifth questions.

45 Second, Article 3a(1)(c) of the Directive, echoing the second recital in the preamble to Directive 97-55, expressly states that features which meet the four criteria referred to above must in addition be compared objectively.

46 As the Advocate General has observed in point 44 of his Opinion, this last requirement is essentially intended to preclude comparisons which result from the subjective assessment of their author rather than from an objective finding.

47 It follows that an obligation to set out expressly in the advertisement the various products which comprise the selections compared and their prices cannot apply here by virtue of such a requirement. Data such as the price of an article or the general level of the prices charged by a chain of stores in respect of a range of products do not appear capable of being the subject of subjective assessment, nor can whether the assessment is objective or subjective be affected by whether or not the products and prices to which the comparison relates are expressly listed.

48 It should, moreover, be noted that Article 2(2a) of the Directive defines comparative advertising as any advertising which explicitly or by implication identifies a competitor or goods or services offered by a competitor, so that advertising may be classified as comparative within the meaning of the Directive where a competitor's products or services, although not explicitly referred to in the advertising, are identified by it by implication.

49 Furthermore, having regard to the interpretative principles recalled in paragraph 22 of the present judgment, it must be stated that in the case of advertisements relating, as is true of the two methods of comparison at issue, to a large number of goods sold by various competing chains of stores, to require that each of the products compared be, in all circumstances, expressly mentioned in that advertisement could affect the very practicability of such advertising methods.

50 Lidl nevertheless relied on the fact that the Court has previously held that any obligation to restrict each price comparison to the average prices of the products offered by the advertiser and those of rival products would be contrary to the objectives of the Community legislature, the Court observing in this regard that comparative advertising must help to demonstrate objectively the merits of the various comparable products and that such objectivity implies that the persons to whom the advertising is addressed are capable of knowing the actual price differences between the products compared and not merely the average difference between the advertiser's prices and those of his competitors (Pippig Augenoptik, paragraphs 81 and 82).

51 It must be pointed out that the Court did not in any way intend by that statement to preclude generally any possibility of comparative advertising that relates to the general level of the prices charged by two competitors in respect of a comparable range of products. In so far as the claimed difference in the general price level is indeed based on real price differences recorded between comparable products and the criterion of comparison thus adopted satisfies, in the light of the advertisement's context, the various requirements laid down by the Directive, in particular by Article 3a(1)(c), such a method of comparative advertising cannot be precluded.

52 First, a comparison designed to demonstrate the difference in the general level of the prices charged by two competing chains of stores in respect of a range of comparable products necessarily presupposes that the actual prices of the comparable products sold by the two competitors are individually compared first.

53 Second, while it is indeed clear that the comparative criterion of the average difference between the prices charged by two competitors or that of the general level of the prices charged by them will appear entirely irrelevant in certain factual contexts which, such as that in Pippig Augenoptik which concerned advertising for pairs of spectacles, relate to an advertisement addressed to consumers called upon to make a single purchase in a shop selling only a certain category of products, the position may be entirely different in other factual contexts. That may be the very situation in the specific context of the present case in which, as is apparent from paragraph 35 above, the general price level is liable to be a particularly relevant criterion of comparison.

54 Having regard to all of the foregoing, the answer to the third question should be that the requirement, laid down by Article 3a(1)(c) of the Directive, that the advertising 'objectively compares' the features of the goods at issue must be interpreted as not signifying, in the event of comparison of the prices of a selection of comparable basic consumables sold by competing chains of stores or of the general level of the prices charged by them in respect of the range of comparable products which they sell, that the products and prices compared, that is to say both those of the advertiser and those of all of his competitors involved in the comparison, must be expressly and exhaustively listed in the advertisement.

Question 5

55 By its fifth question, which it is appropriate to examine third, the referring court seeks to ascertain whether Article 3a(1)(c) of the Directive must be interpreted as meaning that the prices of products, and the general level of the prices charged by chains of stores in respect of their selections of comparable products, constitute verifiable features for the purposes of that provision.

56 As regards the prices of products sold by two competitors, such as, in particular, those referred to by the second method of comparison at issue, it must be stated at the outset that Article 3a(1)(c) of the Directive expressly confirms that the prices of two articles may be included among the features which are simultaneously material, relevant, verifiable and representative and the comparison of which is accordingly in principle permissible in so far as the other conditions that the Directive lays down in order for comparative advertising to be permitted are satisfied. The eighth recital in the preamble to Directive 97-55 likewise confirms that the comparison of the price only of goods and services must be possible if this comparison respects certain conditions, in particular that it not be misleading.

57 As the Court has previously pointed out, the comparing of rival offers, particularly as regards price, is indeed inherent in comparative advertising (Pippig Augenoptik, paragraph 80).

58 It follows that the price of a product constitutes a verifiable feature within the meaning of Article 3a(1)(c) of the Directive.

59 In the light, in particular, of the interpretative principle recalled in paragraph 22 of the present judgment, nothing appears moreover to preclude the same from being true of the general level of the prices charged by chains of competing stores in respect of comparable selections of basic consumables, and of the amount liable to be saved by consumers who purchase such goods from one rather than the other of those competing chains.

60 As soon as the prices of the particular comparable products comprising the selection offered by competing chains of stores have been taken into account for the purpose of determining the general level of the prices charged by them in respect of that comparable selection, both the individual price of each particular product thus taken into account and those general price levels, the amount which consumers who purchase their basic consumables from one rather than the other of those competing chains can expect to save and, finally, the validity of the methods of calculation adopted for those purposes are in principle capable of being subject to verification.

61 It must be pointed out, however, that in order for the prices of the goods comprising a selection of products or the general level of the prices charged by a chain of stores in respect of its selection of comparable goods to be verifiable, it is a necessary precondition that, even though, as is apparent from paragraph 54 of the present judgment, the goods whose prices have been thus compared are not required to be expressly and exhaustively listed in the advertisement addressed to the consumer, they must nevertheless be capable of being individually and specifically identified on the basis of the information contained in that advertisement. The prices of goods can necessarily only ever be verified if it is possible to identify the goods.

62 In light of all of the foregoing, the answer to the fifth question should be that Article 3a(1)(c) of the Directive must be interpreted as meaning that the following constitute, for the purposes of that provision, 'verifiable' features of goods sold by two competing chains of stores:

- the prices of those goods;

- the general level of the respective prices charged by such chains of stores in respect of their selection of comparable products and the amount liable to be saved by consumers who purchase such products from one rather than the other of those chains, in so far as the goods in question do in fact form part of the selection of comparable products on whose basis that general price level has been determined.

Question 4

63 By its fourth question, the referring court seeks to ascertain whether Article 3a(1)(c) of the Directive must be interpreted as meaning that a feature mentioned in comparative advertising satisfies the requirement of verifiability laid down by that provision only if the persons to whom the advertising is addressed are in a position to verify that feature as to its accuracy themselves.

64 It should be noted, first, that while that provision requires, in order to ensure objectivity of comparative advertising, that features compared by the advertising be verifiable, that is to say capable of proof, it does not, on the other hand, contain any detail for the purpose of determining the precise conditions in which, and by whom, those features must be capable of verification as to their accuracy.

65 Second, the objectives pursued by the Directive do not permit the inference that verification of the compared features as to their accuracy should be a possibility available particularly to consumers as opposed to other interested parties, including the competitors involved in the comparison.

66 In this regard, the seventh recital in the preamble to Directive 97-55 states that the establishment of the conditions under which comparative advertising is permitted, which should include criteria of objective comparison of the features of goods and services, must enable it to be determined which practices relating to comparative advertising may distort competition, be detrimental to competitors and have an adverse effect on consumer choice.

67 Article 4 of the Directive, for its part, obliges the Member States to ensure that adequate and effective means exist for securing compliance with the provisions on comparative advertising in the interests of consumers as well as competitors and the general public.

68 Third, the penultimate recital in the preamble to the Directive states that the advertiser should be able to prove, by appropriate means, the material accuracy of the factual claims he makes in his advertising, and may in appropriate cases be required to do so by the appropriate court or administrative authority.

69 More specifically, Article 6 of the Directive obliges the Member States to confer on the administrative authorities or courts called upon to ensure compliance with the Directive the power to require the advertiser, when the circumstances of the particular case so demand and taking into account the legitimate interest of the advertiser and any other party to the proceedings, to furnish evidence as to the accuracy of factual claims in advertising and 'in the case of comparative advertising to require the advertiser to furnish such evidence in a short period of time'. This provision also requires those administrative authorities and courts to be conferred the power to consider factual claims to be inaccurate if the evidence so demanded is not furnished or is deemed insufficient.

70 It follows that, while the advertiser must indeed be in a position to prove, in a short period of time, the factual accuracy of the comparison which he has made, the Directive does not, on the other hand, require him to make such proof available to all interested parties before his advertisement appears.

71 However, the possibility that consumers can obtain from the advertiser, in administrative or judicial proceedings, proof of the factual accuracy of claims in the advertising is not capable of releasing the advertiser, when the products and the prices compared are not set out in the advertisement, from the obligation to indicate, in particular for the attention of the persons to whom the advertisement is addressed, where and how they may readily examine the details of the comparison with a view to verifying their accuracy or having it verified.

72 Such an obligation makes it possible, in accordance with the objective of consumer protection pursued by the Directive, for the persons to whom an advertisement of that kind is addressed to be in a position to satisfy themselves that they have been correctly informed with regard to the purchases of basic consumables which they are prompted to make.

73 Such accessibility of the details of the comparison nevertheless does not mean that the accuracy of the features compared must in all circumstances be capable of being verified by those to whom the advertising is addressed acting in person. It is sufficient for the details allowing such verification to be accessible to those persons under the conditions set out in paragraph 71 of this judgment, in such a way that they may, as a general rule, carry out the desired verification themselves or, more exceptionally and if such verification demands a skill which they do not possess, have it carried out by a third party.

74 Having regard to all the foregoing considerations, the answer to the fourth question should be that Article 3a(1)(c) of the Directive must be interpreted as meaning that a feature mentioned in comparative advertising satisfies the requirement of verifiability laid down by that provision, in cases where the details of the comparison which form the basis for the mention of that feature are not set out in the advertising, only if the advertiser indicates, in particular for the attention of the persons to whom the advertisement is addressed, where and how they may readily examine those details with a view to verifying, or, if they do not possess the skill required for that purpose, to having verified, the details and the feature in question as to their accuracy.

Question 1

75 By its first question, the referring court essentially seeks to ascertain whether an advertisement containing a comparison of the general level of the prices charged by a chain of stores with that of competing chains in respect of their ranges of comparable products and setting out the amount that can be saved by consumers purchasing their basic consumables from one of them must be regarded as misleading advertising for the purposes of Article 3a(1)(a) of the Directive when that general price level is determined on the basis of only some of the products sold by the advertiser, on the ground that such advertising would necessarily give consumers the impression that the advertiser is cheaper over his entire range of products. The referring court wonders, however, whether the fact that the advertising makes it possible to establish, in respect of both the advertiser and his competitors, which and how many products are being compared in order to determine the general level of the prices charged by each of them might prevent the advertising from being in any way misleading. It also raises the question whether it matters from the latter point of view that the advertising indicates the general price level of each of the various competitors involved in the comparison both in relation to the advertiser and between themselves.

76 Article 2(2) of the Directive defines misleading advertising as any advertising which in any way, including its presentation, deceives or is likely to deceive the persons to whom it is addressed or whom it reaches and which, by reason of its deceptive nature, is likely to affect their economic behaviour or which, for those reasons, injures or is likely to injure a competitor.

77 It is for national courts to ascertain in the circumstances of each particular case, and bearing in mind the consumers to which the advertising is addressed, whether the latter may be misleading (see, in particular, Case C-373-90 X [1992] ECR I-131, paragraphs 15 and 16).

78 Those courts must take into account the perception of an average consumer of the products or services being advertised who is reasonably well informed and reasonably observant and circumspect (see X, paragraphs 15 and 16; Case C-210-96 Gut Springenheide and Tusky [1998] ECR I-4657, paragraph 31; Case C-220-98 Estée Lauder [2000] ECR I-117, paragraph 27; Case C-99-01 Linhart and Biffl [2002] ECR I-9375, paragraph 31; and Pippig Augenoptik, paragraph 55). In the present instance, both the advertising methods at issue are addressed not to a specialist public but to end consumers who purchase their basic consumables in a chain of stores.

79 In carrying out the requisite assessment, national courts must also take account of all the relevant factors in the case (Estée Lauder, paragraphs 27 and 30), having regard, as follows from Article 3 of the Directive, to the information contained in the advertising and, more generally, to all its features.

80 The Court has thus held that an omission may render advertising misleading, in particular where, bearing in mind the consumers to which it is addressed, the advertising seeks to conceal a fact which, had it been known, would have deterred a significant number of consumers from making a purchase (X, paragraph 15).

81 With regard, more specifically, to price comparisons, the eighth recital in the preamble to Directive 97-55 states that the comparison of the price only of goods and services should be possible if this comparison respects certain conditions, in particular that it not be misleading.

82 The Court has thus already been led to state that advertising relating to the lower prices of cars that are parallel imports can be considered to be misleading only if it is established that the decision to buy on the part of a significant number of consumers to whom the advertising in question is addressed was made in ignorance of the fact that the lower price of the vehicles was matched by a smaller number of accessories on the cars sold by the parallel importer (X, paragraph 16).

83 Analogously, comparative advertising relating to the general level of the prices charged by competing chains of stores in respect of their comparable ranges of products and to the amount that can be saved by consumers purchasing their basic consumables from one of those chains rather than the other should, for example, be considered to be misleading if it is established, in the light of all the relevant circumstances of the particular case, that the decision to buy on the part of a significant number of consumers to whom that advertising is addressed is made in the mistaken belief that all the advertiser's products have been taken into account in calculating the general price level, and the amount of savings, that are claimed by the advertising. The same must be true if it is established that such a decision is made in the mistaken belief that that amount will be saved by consumers irrespective of the nature and quantity of the products which they acquire from the advertiser or, for example, in the mistaken belief that all the advertiser's products without exception are cheaper than those of his competitors.

84 Such advertising will also be misleading if it is established that the collective reference which it contains to a range of amounts that may be saved by consumers who purchase their basic consumables from the advertiser rather than from competing chains of stores and the failure to specify individually the general level of the prices charged by each of those chains in competition with the advertiser and the amount that can be saved in relation to each of them are such as to deceive a significant number of persons to whom the advertising is addressed as to the amount that they are actually liable to save by purchasing their basic consumables from the advertiser rather than from some particular competitor or other, and to affect their economic behaviour to that extent.

85 Accordingly, the answer to the first question should be that Article 3a(1)(a) of the Directive must be interpreted as meaning that comparative advertising claiming that the advertiser's general price level is lower than his main competitors', where the comparison has related to a sample of products, may be misleading when the advertisement:

- does not reveal that the comparison related only to such a sample and not to all the advertiser's products,

- does not identify the details of the comparison made or inform the persons to whom it is addressed of the information source where such identification is possible, or

- contains a collective reference to a range of amounts that may be saved by consumers who make their purchases from the advertiser rather than from his competitors without specifying individually the general level of the prices charged, respectively, by each of those competitors and the amount that consumers are liable to save by making their purchases from the advertiser rather than from each of the competitors.

86 It is for the referring court to determine whether the advertisements at issue in the main proceedings display such characteristics.

Costs

87 Since 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.

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

1. The condition under which comparative advertising is permissible that is laid down by Article 3a(1)(b) of Council Directive 84-450-EEC of 10 September 1984 concerning misleading and comparative advertising, as amended by Directive 97-55-EC of the European Parliament and of the Council of 6 October 1997, must be interpreted as not precluding comparative advertising from relating collectively to selections of basic consumables sold by two competing chains of stores in so far as those selections each consist of individual products which, when viewed in pairs, individually satisfy the requirement of comparability laid down by that provision.

2. Article 3a(1)(c) of Directive 84-450, as amended by Directive 97-55, must be interpreted as meaning that the requirement, laid down by that provision, that the advertising 'objectively compares' the features of the goods at issue does not signify, in the event of comparison of the prices of a selection of comparable basic consumables sold by competing chains of stores or of the general level of the prices charged by them in respect of the range of comparable products which they sell, that the products and prices compared, that is to say both those of the advertiser and those of all of his competitors involved in the comparison, must be expressly and exhaustively listed in the advertisement.

3. Article 3a(1)(c) of Directive 84-450, as amended by Directive 97-55, must be interpreted as meaning that the following constitute, for the purposes of that provision, 'verifiable' features of goods sold by two competing chains of stores:

- the prices of those goods;

- the general level of the respective prices charged by such chains of stores in respect of their selection of comparable products and the amount liable to be saved by consumers who purchase such products from one rather than the other of those chains, in so far as the goods in question do in fact form part of the selection of comparable products on whose basis that general price level has been determined.

4. Article 3a(1)(c) of Directive 84-450, as amended by Directive 97-55, must be interpreted as meaning that a feature mentioned in comparative advertising satisfies the requirement of verifiability laid down by that provision, in cases where the details of the comparison which form the basis for the mention of that feature are not set out in the advertising, only if the advertiser indicates, in particular for the attention of the persons to whom the advertisement is addressed, where and how they may readily examine those details with a view to verifying, or, if they do not possess the skill required for that purpose, to having verified, the details and the feature in question as to their accuracy.

5. Article 3a(1)(a) of Directive 84-450, as amended by Directive 97-55, must be interpreted as meaning that comparative advertising claiming that the advertiser's general price level is lower than his main competitors', where the comparison has related to a sample of products, may be misleading when the advertisement:

- does not reveal that the comparison related only to such a sample and not to all the advertiser's products,

- does not identify the details of the comparison made or inform the persons to whom it is addressed of the information source where such identification is possible, or

- contains a collective reference to a range of amounts that may be saved by consumers who make their purchases from the advertiser rather than from his competitors without specifying individually the general level of the prices charged, respectively, by each of those competitors and the amount that consumers are liable to save by making their purchases from the advertiser rather than from each of the competitors.