In the Truck Cartel case, the Spanish Supreme Court has refined the evidentiary framework governing antitrust damages actions. According to its judgment of 27 January 2026 (STS 71/2026), accounting documentation may constitute sufficient evidence to prove the purchase price and, consequently, the existence and quantification of harm, even in the absence of original invoices.
This ruling forms part of the Court’s broader effort to balance procedural rigor with the principle of effectiveness in the private enforcement of competition law.
Background: a familiar dispute with an evidentiary twist
The case arises from a follow-on damages action against Renault Trucks following the European Commission’s 2016 decision on the trucks cartel. As in many similar claims, the dispute did not concern only the existence of harm, but also its quantification and, in particular, the proof of the purchase price of vehicles acquired by the claimants many years earlier.
The Audiencia Provincial had denied compensation for two trucks on the basis that the claimants could not produce the original invoices and relied solely on internal accounting records. The Supreme Court overturned this approach.
Accounting records as valid proof of purchase price
A central holding of the Court is the recognition of accounting documentation as probative evidence, even without additional supporting documents.
The Court’s reasoning rests on two key elements. First, where the authenticity of accounting documents is not challenged, they must be treated as fully probative under Articles 319 and 326 of the Civil Procedure Act. In this case, the defendant did not contest the authenticity of the accounting entries at the preliminary hearing, which is decisive for their evidentiary value.
Second, the Court rejects the requirement imposed by the lower court that such documentation be corroborated through additional evidence or linked to formal accounting books. Imposing such a requirement amounts to an excessive and unjustified evidentiary burden.
As a result, the Supreme Court confirms that accounting entries can suffice to establish the acquisition price, particularly in the absence of contrary evidence.
Passage of time and the principle of effectiveness
The Court places significant weight on the temporal context of cartel damages litigation. Many of the relevant transactions took place around twenty years before the claim was brought to trial.
Against this background, the Court considers it unreasonable to require claimants to retain invoices beyond the statutory six-year retention period under the national Commercial Code. Requiring documentation whose preservation is no longer legally mandated would, in practice, impose a stricter obligation than that provided for by law.
Denying probative value to accounting records in such circumstances would make the exercise of the right to damages resulting from an infringement of EU competition law “practically impossible or excessively difficult”, thereby infringing the EU principle of effectiveness.
This reasoning aligns with the Court’s prior case law: procedural requirements cannot be applied in a way that effectively recreates or extends expired legal obligations. The judgment thus reinforces the idea that evidentiary rules must facilitate, rather than hinder, competition damages actions.
A broader evidentiary approach: flexibility over formalism
The judgment reflects a broader trend toward evidentiary flexibility in cartel damages litigation. It implicitly acknowledges the structural asymmetry between claimants and defendants, particularly in access to historical pricing data.
A key element of the decision is the treatment of the claimant’s accounting documents. The Court attaches decisive importance to the fact that their authenticity was not challenged at the appropriate procedural stage, with the result that they must be accepted as evidence of the prices recorded in the claimant’s accounts. In this respect, the judgment highlights the procedural consequences of failing to properly contest documentary evidence in due time.
At the same time, the Court’s reasoning provides some indications, albeit indirectly, as to what may be required from a defendant seeking to rebut the claimant’s case. In particular, while the defendant was not deprived of the opportunity to contest the existence of harm, the Court found that it had not adduced sufficiently convincing evidence capable of undermining the presumption of damage or the reasoning on which it was based. In this context, it should not be understood as a complete absence of defence, but rather as a failure to effectively engage with the evidentiary basis of the claim, by not putting forward a robust alternative explanation and relying on expert evidence that does not adequately address the premises underlying the presumption.
That said, caution is warranted not to overinterpret the judgment. The Court does not articulate a general standard of what would constitute a sufficient substantive rebuttal, nor does it specify in abstract terms the type of evidence that would be required for that purpose. The assessment remains closely tied to the particular circumstances of the case, including the characteristics of the cartel and the weaknesses identified in the defendant’s expert report.
Even so, the decision suggests that, in practice, overcoming the evidentiary framework applicable in cartel damages actions may prove demanding for defendants. Where a presumption of harm is grounded in well-established factual and economic considerations, it is unlikely to be displaced by purely formal objections or by evidence that does not directly confront its underlying logic.
Implications for ERP and CRM data as evidence
Although the case concerns traditional accounting records, its reasoning extends naturally to modern forms of business documentation, including ERP systems and CRM databases.
Several implications can be drawn. First, there is a clear functional equivalence: digital records that reflect transaction data should be treated similarly to accounting entries. In practice, such records may even offer a higher degree of detail and traceability than traditional accounting documents, which can enhance their evidentiary value.
Second, where such data is generated and maintained in the ordinary course of business, it may carry significant weight as evidence, particularly if its authenticity is not sufficiently contested. This is especially so given that such systems are typically used to comply with tax and corporate record-keeping obligations and may, in some cases, be subject to external verification or auditing.
Third, courts should be cautious about requiring additional corroboration where underlying documents are no longer reasonably available.
In this sense, the Court’s approach is technologically neutral yet forward-looking, accommodating evolving forms of record-keeping without imposing outdated evidentiary expectations.
Conclusion
STS 71/2026 represents a further step toward a pragmatic and claimant-oriented evidentiary standard in Spanish cartel damages litigation. By affirming the probative value of accounting documentation, the Supreme Court reduces the risk that formal evidentiary hurdles undermine substantive rights.
More fundamentally, the judgment can be understood as addressing the structural information asymmetry inherent in cartel cases, where key evidence often lies in the hands of the infringing parties and where the passage of time may limit the availability of primary documents. In this context, the Court’s approach contributes to ensuring the practical effectiveness of the prohibition of cartels, by preventing evidentiary standards from rendering damages actions excessively difficult.
More broadly, the judgment signals a degree of judicial openness to a wider range of business records as valid means of substantiating harm. For practitioners, the message is clear: well-structured internal data, even in the absence of original invoices, may suffice where its authenticity is not sufficiently contested and its evidentiary value is not effectively undermined.
As private enforcement continues to evolve, this flexible evidentiary approach is likely to play a decisive role in shaping future competition damages claims in Spain.
By Amelia Mora and Till Schreiber
