ECJ on disclosure of evidence in antitrust damages cases - “plausibility” as lower, but not merely formal, standard of proof

The disclosure of evidence under Article 5(1) was one of the key innovations introduced by Directive 2014/104/EU. Many of the issues surrounding it remain unresolved. In its judgment of 29 January 2026 in case C-286/24 (Meliá Hotels International / Associação Ius Omnibus), the European Court of Justice (ECJ) has now clarified important questions concerning disclosure under Article 5(1) of Directive 2014/104/EU.

Background to the proceedings

The request for a preliminary ruling arose from proceedings before the Supreme Court of Portugal (Supremo Tribunal de Justiça) between the consumer protection organisation Associação Ius Omnibus (“Ius Omnibus”) as claimant and Meliá Hotels International S.A. (“Meliá”) as defendant.

Ius Omnibus had brought a special declaratory action for the disclosure of documents – without yet having filed the intended collective action for damages – which under national Portuguese law is allowed before filing an action for damages. The background was a Commission decision finding an infringement of Article 101 TFEU in the form of a vertical restriction by object committed by Meliá.

The referring court asked whether Article 5(1) of Directive 2014/104/EU also applies to such prior actions for access to evidence brought before an action for damages. It further sought clarification of the standard underlying the “plausibility” requirement in Article 5(1). In particular, it asked whether a Commission decision finding a vertical infringement by object is sufficient to establish the plausibility of a claim for damages.

Applicability of Article 5(1) of Directive 2014/104/EU to prior actions for information

The ECJ confirmed that Article 5(1) applies not only to actions for damages already pending, but also to a prior action for access to evidence, as long as their purpose is to prepare for a later action and provided that national law allows such an action (paragraph 48).

The Court emphasised that the Directive lays down uniform minimum rules on disclosure “in proceedings relating to an action for damages”, which may also encompass preparatory proceedings aimed at obtaining evidence (paragraphs 38–45). Interpreting that wording broadly and teleologically, the Court held that the disclosure mechanism would be deprived of much of its practical effect if claimants were required to bring damages actions without access to the information necessary to substantiate them (paragraphs 41–44).

At the same time, the Court made clear that this does not create an unlimited right to information (paragraphs 45–47). Even in the case of a separate prior action, national courts have to examine whether the substantive requirements of Article 5(2) and (3) are met. In particular:

• The request must be sufficiently specific and clearly defined (paragraph 46; as previously in ECJ, judgment of 10 November 2022, C-163/21, paragraph 64 – PACCAR and Others).
• It must be necessary and proportionate in relation to preparation of an action (paragraph 46; as previously in ECJ, judgment of 10 November 2022, C-163/21, paragraph 64 – PACCAR and Others).
• Non-specific requests for disclosure – so-called “fishing expeditions” – remain inadmissible (paragraph 47).

National courts thus retain a central gatekeeping role in balancing the legitimate interests of all parties and preventing abusive use of disclosure requests.

The standard of “plausibility” within the meaning of Article 5(1) of Directive 2014/104/EU for access to evidence

Under Article 5(1), a claimant must submit a reasoned justification containing reasonably available facts and evidence sufficient to establish the plausibility of its claim for damages.

The ECJ held that “plausibility” is an autonomous concept of EU law. It does not require the claimant to show that it is more likely than not that the conditions for liability are met. Rather, it is sufficient that the assumption that those conditions are satisfied is “reasonably acceptable” (paragraphs 77 and 88). The standard of proof for disclosure is therefore lower than that for the merits of the main action on the merits; otherwise, exercising the right to compensation guaranteed under EU law would be rendered excessively difficult (paragraph 79). The claimant must base its justification on facts and evidence that are “reasonably available” to it. The ECJ sees this as a deliberate limitation of the burden of proof in order to address the typical information asymmetry in antitrust cases (paragraphs 85 and 86).

However, the ECJ stressed that “plausibility” must always refer to all three cumulative conditions for liability: existence of an infringement of competition law, the existence of damage and a causal link between the two (paragraphs 77 and 82; as previously in ECJ, judgment of 22 June 2022, C-267/20, paragraphs 58 and 60 – Volvo und DAF Trucks).

A Commission decision finding an infringement of EU competition law in the form of a vertical restriction by object is not in itself a substitute for demonstration of plausible damage and a plausible causal link by the applicant and therefore does not automatically lead to a right to disclosure (paragraphs 64 to 67, 72). However, it may be given weight in the context of the plausibility check (paragraphs 68 and 69).

Impact on actions for information under German law

Under German law, too, a claim for disclosure of information and evidence based on substantive law (Section 33g(1) GWB) may, in principle, be brought independently prior to an action for damages.

In practice, however, the relevance of such stand-alone actions before German courts is likely to remain limited. Sections 33g GWB, 89b GWB and 142 ZPO already enable requests for disclosure to be made within pending damages proceedings. Given this procedural framework, separate preliminary proceedings are neither necessary nor particularly attractive from a German point of view, especially in light of the duration of proceedings. This applies even more because the feature of necessity of information or evidence ultimately results in a purely practical link between disclosure requests and substantiation duties assumed by the court in the main action.

Whether the reference to prima facie evidence („Glaubhaftmachung“) in Section 33g(1) GWB (in conjunction with Section 294 ZPO) must now be assessed differently in light of the ECJ’s interpretation of “plausibility” remains open. Following the judgment, it would suffice that the existence of damage and a causal link between the infringement and the damage be “reasonable”, and thus be made plausible, without having to demonstrate or prove a preponderance of probability. However, it is unlikely that this would be significantly less than what is currently required when establishing a prima facie case.

Bottom line

Despite the standard of proof being lowered, the ECJ is also setting clear limits to disclosure. Evidence must be described with sufficient precision, and non-specific searches for information, so-called “fishing expeditions”, remain inadmissible (paragraph 47).

Even after the ECJ’s decision, claimants are still required to structure their submissions carefully and to specify the evidence sought as precisely as possible (see also recitals 16 and 23 of Directive 2014/104/EU). A meaningful line of defence against overly broad, unspecific or disproportionate disclosure requests thus remains intact.

The ECJ does not make any express statements regarding horizontal competition infringements in its decision. It therefore remains to be seen whether national courts can impose lower requirements for demonstrating plausible damage where horizontal cartels are involved.

Noerr provides regular advice on relevant antitrust damages cases and private enforcement of European law with its interdisciplinary team. Our Noerr Competition Outlook 2026. gives a broad overview of current developments in the fields of antitrust damages and antitrust law.