Administrative assistance after 2009

The Tax Administrative Assistance Act

The procedural rules for implementing the new treaty clauses were at first laid down in an ordinance. Parliament then adopted the Federal Act on International Administrative Assistance in Tax Matters (Tax Administrative Assistance Act) of 28 September 2012, which entered into force on 1 February 2013. The act governs the execution of assistance under double taxation agreements and other international agreements providing for the exchange of tax information.¹ Three of its provisions illustrate the balance that Switzerland sought to strike between cooperation and the protection of the persons concerned.

Article 3(c) of the act defines group requests as requests for information about several persons who have acted according to an identical pattern of behaviour and who are identifiable by precise specifications. The concept, anticipated by the UBS agreement, thus became part of the general law. Article 7 sets out grounds on which the Federal Tax Administration refuses to enter into a request, among them fishing expeditions and requests that violate the principle of good faith, in particular because they rest on information obtained through acts that are punishable under Swiss law. Article 21a allows the authority, in exceptional cases, to inform the persons concerned only after the transmission of the information, if the requesting state shows that prior notification would defeat the purpose of the assistance. In such cases, a subsequent appeal can only lead to a declaration of unlawfulness.²

Group requests and the courts

The courts developed the practice of assistance through a series of judgments, several of which concerned banks headquartered in Zurich. The most important for the city was the French request concerning UBS. France’s tax authority requested the identities and account balances of approximately 40,000 UBS account holders, on the basis of account numbers that had come from data seized by German authorities in a criminal investigation of 2012 and 2013. On 26 July 2019, by a majority of three to two, the Federal Supreme Court allowed the assistance. The majority held that it sufficed for a list-based request if the suspicion of tax violations extended to part of the group concerned, that the request did not constitute a fishing expedition, and that the explicit assurances of France regarding the principle of speciality were adequate.³ The concern about speciality reflected the parallel criminal proceedings for laundering the proceeds of tax fraud that French prosecutors were conducting against UBS at the time.

The judgment was significant for the financial centre because it confirmed that the principle of good faith did not exclude assistance merely because the requesting state had received the underlying data from another state. The Tax Administrative Assistance Act excludes requests founded on information obtained through acts punishable in Switzerland. The court, however, distinguished between data that the requesting state had obtained through its own active conduct, such as a purchase, and data that had come to it in other ways. That distinction has occupied the courts ever since.⁴ For the practitioner advising a client with a legacy account in Zurich, the lesson was that the procedural protections of the act offered delays and occasional victories but no reliable protection against disclosure.

Notes

1. Federal Act on International Administrative Assistance in Tax Matters (Steueramtshilfegesetz, StAhiG) of 28 September 2012, SR 651.1, Articles 1, 3(c), 7 and 21a, text available at https://www.lexfind.ch/tolv/168654/de. ↩
2. Ibid., Articles 3(c), 7 and 21a. The Federal Council’s report of 18 December 2013 (n. above) describes the admission of group requests as a consequence of the international standard and explains that such requests identify persons through patterns of behaviour. ↩
3. Federal Supreme Court, judgment 2C_653/2018 of 26 July 2019, summarised in “2C_653/2018: Amtshilfe an Frankreich zur Feststellung der Identität von UBS-Kunden”, daten:recht (Walder Wyss), https://datenrecht.ch/amtshilfe-an-frankreich-zur-identitaet-von-ubs-kunden/. ↩
4. Swiss Federal Supreme Court, judgment of 17 March 2017, BGE 143 II 224, https://servat.unibe.ch/dfr/bge/c2143224.html, consideration 6.4: a requesting state “qui achèterait des données bancaires qu’il utiliserait ensuite pour former des demandes” would not act in good faith. The case concerned a French request linked to the data taken by Hervé Falciani from the Geneva subsidiary of HSBC. The details of the later case law lie outside the scope of this chapter. ↩

For general information only. This article does not constitute legal or tax advice, does not replace advice on an individual case and creates no lawyer-client relationship. It reflects the legal position as of September 2025.