Federal Supreme Court, 21.07.2026, 2C_393/2026
Facts
The German Federal Central Tax Office submitted a request for administrative assistance to the Federal Tax Administration (FTA) under the double taxation convention between Switzerland and Germany (DTC CH-DE). The request concerned the German company B.________ GmbH, which, in collaboration with the Swiss company A.________ AG, operates a business model for delivering goods to Swiss end customers. The requesting authority highlighted the complexity of the business relationships, the centralized data management via A.________ AG's software, and the lack of cooperation in verifying transfer prices, thereby justifying its request for information held by the Swiss authorities regarding A.________ AG. (A.)
On December 11, 2025, the FTA issued a final decision granting the request for assistance and ordering the transmission of the required information. Both companies, A.________ AG and B.________ GmbH, appealed this decision to the Federal Administrative Court (FAC), requesting its annulment and the rejection of the assistance request. (B. and B.a.)
In a judgment dated June 18, 2026, the FAC partially upheld the appeal. It ordered the FTA to perform certain redactions and to explicitly draw the requesting authority's attention to the usage restrictions and confidentiality obligations provided for inArt. 27 para. 2 DTC CH-DE. Otherwise, the FAC dismissed the appeal. Both companies then filed an appeal in public law matters with the Federal Supreme Court, seeking the annulment of the FAC's judgment and the rejection of the assistance request. (B.b. and C.)
Legal Grounds
The Federal Supreme Court reviews its jurisdiction and the other admissibility requirements for an appeal of its own motion and with full power of review. UnderArt. 83 let. h of the Federal Supreme Court Act (FSCA), an appeal in public law matters is inadmissible against decisions concerning international administrative assistance, with the exception of administrative assistance in tax matters. (consid. 1.)
For administrative assistance in tax matters, the admissibility of the appeal is governed byArt. 84a FSCA. Such an appeal is only admissible if the case raises a legal issue of principle or if it is, for other reasons, a particularly important case within the meaning of Art. 84 para. 2 FSCA. It is incumbent upon the appellant to demonstrate how one of these conditions is met, unless this is manifestly the case. (consid. 1.1.)
A legal question of principle arises if the decision can serve as a guide for practice, particularly for a large number of similar cases, or if it is a novel issue requiring clarification by the highest judicial authority. A particularly important case is admitted only with restraint, notably in the event of a violation of fundamental procedural principles or serious procedural failures abroad. The Federal Supreme Court has broad discretion in determining whether such a case exists. (consid. 1.1.1. and 1.1.2.)
The interpretation of a request for administrative assistance must be carried out in light of the principle of good faith, as enshrined inArticle 26 of the Vienna Convention on the Law of Treaties. The requested State must choose, among possible interpretations, the one that ensures the effective application of the convention and does not contradict its purpose and object, so as not to hinder the exchange of information. (consid. 1.3.1.)
Application to the specific case
The appellants first raised a legal question regarding data protection, arguing that the transmission of information before the concerned third parties were notified deprived them of an effective remedy within the meaning ofArticle 13 ECHR. The Federal Supreme Court notes that this issue has already been settled by its case law. It has indeed already ruled that the rights of third parties not involved in the assistance procedure are sufficiently protected by the legal remedies provided under data protection legislation. There is therefore no reason to re-examine this question, which does not possess the character of a principle. (consid. 1.2, 1.2.1. and 1.2.2.)
Secondly, the appellants contested the transmission of tax returns of A.________ AG on the grounds that they had not been specifically requested by the German authority, which they claimed amounted to unauthorized "spontaneous" assistance. The Federal Supreme Court reduces this issue to a matter of interpreting the assistance request. It reiterates that this interpretation must be conducted according to the principle of good faith. The question of whether the tax returns were implicitly covered by the request is a matter of assessment specific to the case at hand, lacking general significance. As the case law on the method of interpretation is well-established, this does not constitute a legal question of principle. (consid. 1.3, 1.3.2. and 1.3.3.)
Finally, the appellants alleged the violation of several procedural guarantees (right to be heard, prohibition of arbitrariness, good faith), but without demonstrating how this would constitute a qualified violation of fundamental procedural principles, nor asserting the existence of a particularly important case within the meaning of Art. 84a LTF. The Federal Supreme Court therefore concludes that this admissibility requirement is also not met. (consid. 1.4.)
Outcome
The Federal Supreme Court finds that none of the admissibility requirements provided for in Art. 84a LTF are met. Consequently, it does not enter into the merits of the public law appeal. (consid. 1.5. and 1.)
Court costs, amounting to CHF 5,000, are charged to the appellants, in equal shares and jointly and severally. No legal costs are awarded. (consid. 2. and 3.)