Courts throughout Europe increasingly adopt a minimum damages approach in antitrust cases, unanimously presuming at least a 5% overcharge, driven by grounds of compensation, effectiveness and deterrence. Recent judgments – from the CAT (UK) to the Spanish Supreme Court, Norway’s courts, the Court of Appeal in Stuttgart, the Dieselgate rulings of the German and Austrian Supreme Courts, and finally the European Court of Justice – point to a converging practice and a structured approach to quantifying damages across the EU.
Introduction
The full effectiveness of the competition rules laid down in Articles 101 and 102 of the Treaty on the Functioning of the European Union (TFEU) requires that anyone can seek compensation before national courts for harm resulting from violations of those provisions. This is well established in the case law of the Court of Justice of the EU (CJEU). The EU Antitrust Damages Directive (Directive 2014/104) further stipulates a legal presumption – already recognised by many national courts – that infringements in the form of cartels (e.g., price fixing, market sharing or customer allocation) cause harm.
The quantification of that harm, however, remains highly contentious in all cartel damages proceedings. Only a few Member States provide for a statutory presumption regarding the amount (see Romania: 20% overcharge, Hungary and Latvia: 10%), and these presumptions are rebuttable. Defendants regularly argue that they fall within the (empirically rare) exceptional category of cases in which a cartel had no, or only marginal, market effects – even where long‑running collusion has been proven despite the constant risk of antitrust penalties.
By contrast, claimants must quantify the harm suffered to substantiate their damages claims, or at least provide sufficient evidence to enable a judicial estimation. This is often costly, and claimants frequently lack access to the necessary data and evidence. Sometimes, economic expert opinions are required, the cost of which may even exceed the expected compensation (notwithstanding other litigation risks). This often deters claimants from pursuing legitimate claims for damages at all, thereby undermining in practice the effective enforcement of EU competition law.
A new development, however, may shift this dynamic. Where it is sufficiently likely, based on the facts of the infringement and the market conditions, that a claimant has suffered harm, courts across Europe increasingly accept the notion of a “minimum amount”. To address the shortcomings of economic damage analyses and ensure the effectiveness of EU competition law, those courts unanimously assume at least a “5% overcharge” on cartelised goods or services. Recent CJEU case law appears to support this approach.
Starting point: truck cartel
The emergence of the 5% benchmark can be traced primarily to the well‑known truck cartel, which has significantly shaped the development of private antitrust enforcement throughout Europe.
Reino Unido
Following the European Commission’s 2016 infringement decision finding that several truck manufacturers had colluded for 14 years in setting gross list prices, the London Competition Appeal Tribunal (CAT) delivered its judgment on 7 February 2023 (Royal Mail & BT v DAF [2023] CAT 6). It awarded £38.5 million in damages and interest to Royal Mail and BT against DAF. Convinced that an overcharge existed, the CAT ultimately wielded the “broad axe” to place a value on it. After extensive hearings, neither party’s experts nor their regression models persuaded the tribunal. According to the CAT, “no regression model” would yield a definitive solution due to data imperfections and the complexity of the task.
In the end, the CAT’s “fair and reasonable” solution was Solomonic: it assumed a 5% overcharge on the value of commerce (VoC) for both Royal Mail and BT for the entire relevant period – roughly half of what the claimants had argued, while DAF denied any damage whatsoever.
DAF’s appeals were subsequently dismissed ([2024] EWCA Civ 181 y UKSC 2024/0052).
España
The approach taken by the CAT reflects an emerging European convergence toward judicial estimation of cartel harm where precise quantification proves impracticable. In a landmark judgment of 12 June 2023 (ECLI:ES:TS:2023:2475), the Spanish Supreme Court (Tribunal Supremo, TS) held that the characteristics of the truck cartel – its subject matter, participants, market coverage, duration and geographical scope – were sufficient to presume significant harm. However, the court considered an exact quantification of that harm impossible. Referring to the CAT’s reasoning in Royal Mail and the limitations of the extensive and costly expert hearings conducted there, as well as to the effectiveness of Article 101 TFEU, the TS thus estimated a “minimum percentage of 5%” of the costs of the affected lorries as the amount of harm.
According to the TS, this minimum is both foreseeable y prudently set for a cartel of this nature. Defendants may, however, demonstrate that the actual harm was lower, while:
“As long as it is not proven that the amount of the damage was higher than the minimum percentage of 5%, the plaintiff cannot claim compensation in excess of that percentage.”
Thus, the 5% overcharge serves as a lower bound, which injured parties may rely upon where they cannot prove a higher amount – e.g., because their economic expert reports, if any, are inadequate (further details aquí).
In fact, on 18 December 2025, the TS accepted a higher overcharge in another truck cartel case (ECLI:ES:TS:2025:5861; s.a. this case report). Upholding a judgment of the Court of Appeal of A Coruña, the TS confirmed that the expert opinion of the plaintiff in that case convincingly demonstrated an overcharge of 16.35%, while the expert opinion of the defendant, which assumed “zero damages”, was not credible in view of the facts established by the European Commission. The Appeal Court only applied a one‑third reduction to account for uncertainties in the plaintiff’s report, arriving at a final overcharge of slightly above 10%.
Noruega
A similar approach is reflected in the ruling of the Borgarting lagmannsrett of 17 March 2025, which also attracted some attention. This Norwegian appellate court found that the truck cartel had caused an overcharge of 10% of the chassis value for trucks purchased by Posten Bring, a state‑owned postal and logistics group, in Norway. For trucks purchased by subsidiaries in Sweden and Slovakia, the court set the overcharge at 5%, noting that Posten had supplied less evidence concerning those markets.
Over the course of 34 hearing days, the court had examined testimony from 18 economic experts. The results of the various regression models diverged widely, and none produced a reliable conclusion, underscoring that econometric precision cannot be required where inherent data limitations make such models unstable or misleading. The court therefore aligned itself with the CAT’s caution against “spurious accuracy” in Royal Mail.
Instead, the court assessed all available evidence – including the Commission’s infringement decision, economic theory and cartel meta‑studies – and awarded Posten approximately NOK 117 million (around €10 million) plus interest in damages.
Norway’s Supreme Court declined to hear the defendants’ appeals (for all of that, see this case report).
German appeal court (Stuttgart, 2025): “regular corridor of 5% to 25%” cartel overcharge
The next significant development in this line of case law is the sentencia of the Higher Regional Court (Oberlandesgericht, OLG) of Stuttgart of 20 November 2025. This decision is a must-read not only because it concerns a cartel other than the truck cartel (namely, the European bathroom fittings cartel), but also because the OLG developed a comprehensive model for estimating cartel overcharges and pass‑on.
Like the other courts discussed above, the OLG expressed fundamental doubts about the suitability of regression analyses and other economic models (e.g. cost-based price control) for quantifying cartel‑induced harm in legal disputes. Requiring such analyses in every case, the court noted, would make the enforcement of damages claims excessively difficult. Gathering the necessary data is contentious, complex, time‑consuming and costly – without guaranteeing a clear or reliable outcome. The court emphasised that the “inevitable degree of uncertainty” in establishing the hypothetical competitive price must not be borne by the injured parties, since that uncertainty stems directly from the illegal collusion.
Therefore, relying on Article 17(1) of Directive 2014/104, the OLG reaffirmed the court’s power to estimate harm. To do so, it developed a “methodologically independent” and structured five‑step test aimed at ensuring a realistic and procedurally efficient quantification, based on economic meta‑studies, empirically validated principles and the facts of the specific case. By establishing such a framework, the OLG reduces evidentiary burdens while maintaining analytical structure and transparency in judicial damage estimation. The five steps are:
- Establishing the existence of an antitrust‑related price effect, i.e., an overcharge (taking into account the presumption of cartel‑induced harm);
- Classifying the overcharge within an “estimation corridor;”
- Refining the estimate within that corridor through a detailed assessment of relevant factors (including aspects of the collusion, how it was organised, market conditions, and demand);
- Assessing pass‑on of the overcharge to the claimant (where the claimant is an indirect purchaser); and
- Considering the passing‑on defence. This involves determining whether the defence fails from the outset – in line with the case law of the Federal Court of Justice – as its acceptance would effectively eliminate the defendants’ liability in circumstances where indirect customers are not expected to bring their own claims, such as in cases of dispersed damages (as in the present case before the OLG).
The second step is particularly important in the present context (for a broader case review, see aquí). According to the OLG, once a price effect has been established, it can generally be assumed that the overcharge at the first market level (i.e., in transactions between cartelists and their direct customers) falls “typically within a regular corridor of 5% to 25%” of the price paid. This range corresponds to a standard deviation of 10 percentage points around the reference value of 15%, which economic meta‑studies (Connor, Oxera, Smuda, Boyer/Kotchoni) identify as a conservative median of cartel‑induced price increases in Europe. This reinforces that the corridor is grounded not in abstraction but in empirical reality. Germany’s Federal Court of Justice has also accepted the 15% figure as a lump‑sum benchmark for cartel damages under standard business terms (as in Rails Cartel VI).
The “regular corridor” does not prevent courts from estimating damages outside this range in exceptional cases. However, such deviations should be rare, especially with regard to the lower limit. As the OLG explained:
“The lower value of 5% appears plausible and economically sound in the case of a cartel where, according to the first stage of assessment, a significant price effect can be assumed with a high degree of probability. It can therefore serve as a basis for estimating minimum damage if the circumstances of the case allow sufficient conclusions to be drawn about the occurrence of damage, but doubts remain as to whether it falls within the lower corridor (less than 5%).”
The OLG expressly allowed an appeal to the Federal Court of Justice.
In parallel: the “compensation bracket” in Dieselgate (CJEU, 2025)
Starting point: Germany
In the context of the so‑called diesel emissions scandal (Dieselgate), the Federal Court of Justice (Bundesgerichtshof, BGH) had already applied the idea of channelling compensation for breaches of EU law into a defined estimation range, on its own initiative and in an even stricter manner. This illustrates that the underlying normative rationale is not sector‑specific but flows from the general EU‑law requirement of effectiveness, especially in terms of deterrence.
Following the CJEU’s Mercedes‑Benz Group ruling of 2023 (C-100/21), the BGH held in a judgment of 26 June 2023 that the purchaser of a motor vehicle equipped with a defeat device prohibited under EU law – namely, Regulation (EC) No 715/2007 and Directive 2007/46/EC (Framework Directive) – may claim damages under national law for having bought the vehicle at a price higher than would have been paid absent the infringement. The amount of the damage is to be assessed by the trial judge. However, according to the BGH, the loss could never be below 5% nor exceed 15% of the purchase price.
The BGH justified this range by normative grounds, referring to the “requirements of EU law” identified by the CJEU: sanctions for a violation of the relevant EU provisions must be “effective, proportionate and dissuasive”. Damages exceeding 15% would be disproportionate in cases involving illegal defeat devices, which the BGH described as “objectively comparatively minor” infringements. At the same time, the lower limit of 5% is justified by the preventive function of damages and, therefore, the effectiveness principle:
“For reasons of effectiveness under EU law, the estimated damage cannot be less than 5% of the purchase price paid. […] The damage estimation must lead to a sanction that is also tangible for the vehicle manufacturer in terms of amount. […] It is sufficient if, on the one hand, each sanction taken individually is associated with a not insignificant loss in relation to the manufacturer’s earnings associated with the transaction and, on the other hand, the sanctions for many legal infringements as a whole can bring about a change in behaviour in terms of compliance with all legal acts. This is the case with a lower assessment limit for damages of 5% of the purchase price paid.”
(Omissions added)
Confirmation in Austria
The BGH’s reasoning has been expressly adopted in Austria. In a decision of 28 September 2023, the Austrian Supreme Court (Oberster Gerichtshof) confirmed that adequate compensation for Dieselgate cases lies within a range of 5% (“as the lower limit for reasons of effectiveness under EU law”) and 15% (“as the upper limit for reasons of proportionality under EU law”) of the price paid, “even disregarding the evidence submitted by the party (e.g. expert opinions).”
Approval by the European Court of Justice
Soon thereafter, a lower German court referred the issue back to the CJEU. The referring court questioned whether a blanket 5-15% range might violate the effectiveness principle, given that the reduction in vehicle value caused by defeat devices would often exceed the schematic upper limit of 15%.
In its judgment of 1 August 2025 (C-666/23), the CJEU essentially confirmed the BGH’s approach. It reiterated that sanctions for violations of EU law must be effective, proportionate and dissuasive. On that basis alone, the Court held:
“[104] [T]he determination by a Member State of such a compensation bracket, consisting of a minimum and a maximum percentage of the purchase price, with a view to fixing the amount of adequate compensation which the purchaser of the vehicle concerned must receive, cannot, as a matter of principle, be regarded as contrary to EU law either, provided that that bracket does not lead to inadequate compensation for the loss or damage suffered by the purchaser of a vehicle fitted with a defeat device. […]
[106] It is for the referring court to ascertain whether or not the compensation bracket […] makes it practically impossible or excessively difficult [for the claimants] to obtain adequate compensation for the loss or damage suffered.”
(emphasis, omissions, and clarification in square brackets added)
This means that EU law does not preclude the establishment of a minimum percentage – such as 5% – when estimating damages. At the same time, compensation must not be capped at a level that fails to provide adequate reparation for the harm actually suffered. In short, the CJEU endorses the principle of minimum damages for reasons of effectiveness.
The wheel turns full circle: back to both the truck cartel and Stuttgart
At first glance, the marketing of a car fitted with an illegal defeat device and conduct prohibited under competition law may appear unrelated. Yet in both situations, the infringements give rise to claims for compensation under EU law for the financial losses suffered. This raises the question of whether, and to what extent, the Dieselgate case law also applies in cartel cases (for this, see already aquí), especially in light of the above‑mentioned decisions of the Spanish Supreme Court (TS) and the “regular corridor” approach taken by the Stuttgart OLG.
Indeed, the Regional Court (Landgericht, LG) of Stuttgart has provided a convincing answer in a series of 2025 judgments concerning the truck cartel. In its decision of 27 February 2025, for example, the LG held (emphasis added):
“[437] In the present case, the reasons of effectiveness under EU law also require a minimum damage of 5%. Cartel damages are not only subject to an estimate [pursuant to Section 287 of the German Code of Civil Procedure], but their effective enforcement and assessment are also required by primary law and laid down in Articles 4 and 17(1) of Directive 2014/104 (see also its Recitals 3 and 45). It can be left open whether, in this case or in general in actions for antitrust damages, there is a need for a normative limitation of the discretion to estimate damages in accordance with the case law of the BGH in the ‘diesel scandal’ case in the sense of a minimum damage threshold ([reference to the BGH judgment of 26 June 2023 mentioned above]). Nevertheless, it can be stated that the requirement for an ‘effective, proportionate and dissuasive sanction’ laid down in Article 46 of the Framework Directive and Article 13(1) of Regulation (EC) No 715/2007 does not constitute a special feature of illegal defeat devices. Rather, violations of EU law are generally to be sanctioned in this way, including in competition law (see Krüger, Mit Voll(ab)gas zum kartellrechtlichen Mindestschaden?, Neue Zeitschrift für Kartellrecht [NZKart] 2024, p. 152 […]). Claims for damages serve not only to compensate private parties for damages, but also the public interest in the practical effectiveness of Article 101 TFEU and Section 1 [German] Competition Act ([reference to, e.g., CJEU, judgment of 6 October 2021, C‑882/19, Sumal, paras. 34 et seqq.]). Furthermore, it must be taken into account that the prevention objective (which also characterises antitrust damages) has long been recognised as a factor in assessing compensation for non‑material damages.”
(emphasis, omissions, and clarifications in square brackets added)
Comment
First, it must be stressed that assuming minimum damages does not give claimants carte blanche. The prerequisite remains that the occurrence of harm caused by the competition law infringement must first be established. This is consistent across all the case law discussed above.
Second, the CJEU’s 2025 Dieselgate ruling reiterates that financial compensation for a breach of EU law must be adequate. This means the harm actually suffered must be made good in full under national rules (see already the 1993 CJEU’s Marshall judgment, paras. 26 et seqq.). The same principle applies to infringements of EU competition law (see Article 3 of Directive 2014/104). As the Stuttgart LG notes, damages must also comply with the requirement that sanctions be effective, proportionate and dissuasive. Against this background, the reasoning of various national courts which – within their power to estimate the harm (see Article 17(1) Directive 2014/104) – have set a lower threshold for cartel damages appears conclusive.
Third, an overcharge of 5% of the purchase price paid marks a widely accepted and reasonably conservative lower bound for minimum damages, at least in cases of hardcore infringements such as cartels. Plaintiffs remain free to claim higher amounts if they can sufficiently substantiate them, for example through robust economic analysis. Therefore, despite judicial scepticism towards complex econometric models, expert input remains valuable.
Fourth, conversely, an overcharge of less than 5% can only be justified in exceptional circumstances and only where it is beyond doubt. No credible analysis may point to an equally high or higher overcharge. This reflects the very purpose of minimum damages within the framework of adequate compensation.
Moreover, minimum damages are not solely compensatory but also aim to ensure full compliance with the law. In the Mercedes‑Benz Group ruling – on which the BGH built its compensation bracket – the CJEU made the avoidance of unjust enrichment (i.e., over-compensation) expressly “subject to” the effectiveness principle of EU law (paras. 93-94). From a broader effectiveness perspective, assessing the lower limit for cartel damages may therefore also require taking into account the considerable obstacles faced by many claimants, such as the asymmetry of confronting multiple, often economically powerful defendants and numerous experts. Viewed from this angle as well, a minimum overcharge of 5% is both justified and, if anything, conservative.
By Carsten Krüger
