Private Enforcement of the DMA: Germany Takes the Lead with the 1&1 Mail & Media/Google (Gmail) Case

Private enforcement of the Digital Markets Act (DMA) is now a reality, and the judgment of the Regional Court of Mainz (Case 12 HK O 32/24) in the 1&1 Mail & Media/Google (Gmail) case, delivered on 12 August 2025, represents one of its first judicial expressions in Germany. This decision follows the path opened by the judgment of the Higher Regional Court of Cologne of 23 May 2025 (Case 15 U K 2/25, see blogpost here), marking the beginning of a new phase in which the public enforcement of the DMA will have to coexist – hopefully peacefully – with its private enforcement.

In the absence of a harmonised European framework for private DMA damages actions similar to Directive 2014/104/EU, this judgment applies the domestic legal regime originally designed for the private enforcement of antitrust law and extended to the DMA through the Eleventh Amendment to the GWB. Instead of relying on damages actions, however, the case relies on injunctive relief. Everything suggests that Germany’s particularly proactive approach to the regulation of digital platforms will also extend to the development of private enforcement under the DMA.

The Ruling of the Regional Court of Mainz

In its judgment of 12 August 2025, the Regional Court of Mainz ordered Alphabet/Google to cease the preferential treatment granted to its email service (Gmail) over competing providers during the registration process for the creation of a Google account, within the context of setting up and using Android devices.

According to the Court, Alphabet/Google’s conduct infringed the anti-tying clause in Article 5(8) DMA, as it made access to the gatekeeper’s core services (such as Google Play, YouTube or Chrome) conditional upon subscribing to its email service. Arguably, the conduct could also have been assessed under the self-preferencing prohibition in Article 6(5) DMA.

Although the judgment adopts the form of a negative injunction (cease and desist), its implementation in practice requires Alphabet/Google to adapt the registration process for the relevant services, by designing new choice screens for end users. The mode of compliance is left to Alphabet/Google’s discretion. However, the Court cautions that, if the option to register by phone number – introduced by the defendant during the proceedings – is retained, the automatically generated Gmail address must neither be visible nor usable to users.

Beyond the substantive interpretation of the DMA, the case raises several issues of great interest from the perspective of its private enforcement. In competition law, damages actions following a finding of infringement by a competition authority (follow-on actions) have traditionally prevailed. By contrast, the claimants in this case (providers of alternative email services) brought an injunction action rather than a damages action without relying on any prior decision of the European Commission (a move that was also more successful for abuse of dominance private enforcement cases in the past). At first sight, this already raises some doubts, as several authors have expressed their disapproval of the possibility of bringing stand-alone actions under the DMA, given the inherent risk of internal market fragmentation.

Between Cooperation and Judicial Autonomy

A particularly interesting aspect of the case concerns Alphabet’s/Google’s request for a stay of the proceedings. The defendant argued that the design of its registration process was the subject of a “regulatory dialogue” in which the European Commission had even assessed the measures positively. A national decision to the contrary, it claimed, could breach the duty to respect Commission decisions under Article 39(5) DMA, the principle of sincere cooperation enshrined in Article 4(3) TEU, and the case-law stemming from Masterfoods.

Judicial decisions handed down in horizontal civil proceedings between private parties produce, once final, res judicata effects inter partes. This does not preclude the European Commission as the sole public enforcer of the DMA from subsequently adopting an administrative (vertical) decision of erga omnes effect that contradicts the national judgment. Such duplication opens the door to potential conflict: hypothetically, the Commission could validate the measures initially adopted by Google, contradicting the ruling of the Mainz Court.

However, the Regional Court of Mainz rejected the request for suspension, arguing that “irrespective of whether the Commission has already initiated proceedings in this sense, there is no statement as to what decision the Commission intends to adopt.” In fact, there is no evidence of any decision having been adopted or even envisaged within a formally initiated procedure. At first glance, the so-called “regulatory dialogue” with the European Commission amounts to nothing more than an exchange of information or informal contact, insufficient to justify the suspension of the action. The Commission, which was aware of the case, could have clarified this point but chose not to intervene as amicus curiae under Article 39(3) DMA. Yet, the Commission generally very rarely engages in amicus curiae submissions in national courts. The judges in Mainz interpreted this institutional silence as an absence of conflict. This more relaxed reading of Article 39(5) appears reasonable, as it prevents gatekeepers from invoking cooperation with EU institutions as a dilatory strategy.

Validity and Applicability of the Ruling Within the EU

The court stated – rather boldly – that “the ruling was also not limited in its tenor to apply within Germany, as the DMA applicable here has Europe-wide effect (…) Ultimately, the validity of the judgment for the European Union is likely to arise from the meaning and purpose of the regulations.”

Although its intentions may be legitimate – being based on the uniformity and effet utile of the Regulation – such statements are misguided. As any other EU Regulation, the DMA is directly applicable (Article 288 TFEU), and the national judge who applies it acts as an organ of the Union, but this does not mean that its ruling has binding effects beyond its own Member State.

In competition law, final judgments delivered in other Member States are regarded merely as “prima facie evidence of an infringement” in the context of follow-on damages actions (Article 9(2) of Directive 2014/104/EU). Ultimately, uniformity in the interpretation of EU law is ensured through the case-law of the Court of Justice, to which national courts may refer questions under Article 267 TFEU.

Nevertheless, the interpretation of the DMA by a national court forms part of the European legal acquis and may therefore be taken as a reference by other courts across the Union. This interpretative or persuasive reach is probably what underlies the Court’s words, even if they are not entirely accurate.

What is clear, however, is that beyond the strictly legal dimension, the ruling may have a European impact in practice. Compliance with the order may lead Google to modify the registration process for all users across the EU. Failing to do so could expose the company to parallel litigation in other Member States, where courts might follow the same reasoning.

This pattern is common among digital platforms operating beyond national borders, as domestic litigation often escalates to the European level. We saw this, for instance, when Google introduced a “Reject All” button in its cookie banners following the CNIL’s enforcement action in France, or when Meta launched its “pay-or-consent” model as a result of its litigation with the Bundeskartellamt, initially limited to Germany.

In conclusion

This judgment marks an important step in the private enforcement of the DMA, as the Court has faced novel questions for which there are few, if any, precedents. In these circumstances, the European Commission missed an opportunity to intervene at a time when – given the still nascent nature of private enforcement under the DMA – greater institutional involvement would be most welcome to provide legal certainty. This attitude suggests that the cooperation mechanisms provided for in the DMA may fall into the same disuse as their antitrust counterparts in Articles 15, 16 Regulation 1/2003.

Furthermore, although the Court may have overstated its point when referring to the “validity of the judgment for the European Union”, it is likely that its ruling will, in practice, influence Alphabet/Google’s behaviour and guide the actions of other national courts and even the European Commission itself.