Article 47: the criminal protection of banking secrecy

The original provision

Article 47 stood in the penal chapter of the Act, among provisions that punished the publication of false accounts, the refusal to provide information to the auditors and other breaches of the statute. Its structure was simple. Anyone who, as a member of a bank’s governing bodies, as an employee, agent, liquidator or commissioner of a bank, as an observer of the Banking Commission or as a member or employee of a recognised audit firm, breached the duty of silence or professional secrecy, and anyone who induced or attempted to induce such a breach, was liable to a fine or to imprisonment.¹ Three features of the provision deserve emphasis, because they explain both its later reputation and its limits.

First, Article 47 did not define the secret it protected. It presupposed the existence of a duty of secrecy grounded elsewhere, in the contract between bank and client and in the protection of personality, attaching a criminal sanction to its breach. Matthias Michlig, in a detailed analysis of the offence, points out that the provision was formulated with a deliberately open scope and that the Federal Council itself, in its dispatch on the revision of the Act in 1970, stated that banking secrecy followed from the general provisions of the Code of Obligations.² The criminal norm therefore reinforced a civil-law obligation. It did not create a new substantive right.

Second, the provision was addressed to insiders. It bound the people who worked in or for a bank and the people who supervised or audited it. It did not, in its original form, punish an outsider who received information from a disloyal employee and made use of it, unless the outsider had induced the breach. This gap, which remained open for eighty years, became acutely relevant when data carriers with client information began to be sold to foreign tax authorities after 2006.

Third, Article 47 did not prevail over other federal or cantonal duties to testify or to provide information to an authority. The duty of secrecy applied between the bank and private third parties and, in principle, also between the bank and foreign authorities. It gave way where Swiss law required disclosure, for example in criminal proceedings, in debt enforcement and bankruptcy, in inheritance matters or, within limits, in tax proceedings. The reservation in favour of statutory duties to testify and to inform, which is today found in paragraph 5 of Article 47, has always been essential to a correct understanding of the provision.³ Banking secrecy was never an absolute shield in Swiss domestic law. Its protective force was greatest where Swiss law provided no route to the information. That was above all the case for foreign tax authorities and, in the ordinary assessment procedure, for Swiss tax authorities as well.

The revisions of 1971, 2009 and 2015

The provision was restructured in the course of the general revision of the Banking Act that Parliament adopted in 1971. The circle of persons bound by secrecy was brought up to date, while the offence was given the form that, in its essentials, it still has today: intentional disclosure of a secret entrusted to a person in a bank capacity or observed in that capacity, the attempt to induce such a disclosure, and a separate offence for negligent breach.⁴ The offence was prosecuted ex officio by the cantonal authorities, without any need for a complaint by the client. After further amendments in 2004 and 2009, the Federal Supreme Court has had to distinguish between the versions in force from 1 July 2004 and from 1 January 2009 when judging conduct that stretched over several years.⁵ The amendment in force from 1 January 2009 accompanied the creation of the Swiss Financial Market Supervisory Authority and raised the maximum penalty for intentional breach to a custodial sentence of three years, with a fine of up to 250,000 francs for negligent breach.⁶

The most important change of recent decades concerned the data trade. From 2006 onwards employees of several Swiss banks, and of Swiss banks’ foreign subsidiaries, copied client data and sold or passed them to the tax authorities of Germany and other states. Because Article 47 in its old form punished only the insider, the buyers and intermediaries were outside its reach unless they had instigated the breach. On 16 September 2014 the National Council, as the first chamber, adopted by 126 votes to 58 an amendment based on a parliamentary initiative from the ranks of the FDP. Its supporters described data theft as a serious violation of the clients’ privacy and a threat to confidence in the financial centre, while the Social Democrats and the Greens objected that the higher penalties sent entirely the wrong signal at a time when Switzerland was moving to the automatic exchange of information. The reform raised the maximum penalty to five years for anyone who obtains a financial advantage for himself or another through the breach, introduced a penalty of up to three years for third parties who pass on or exploit secrets disclosed to them in breach of the duty, and made corresponding changes to the Collective Investment Schemes Act and the Stock Exchange Act.⁷

The new provisions entered into force on 1 July 2015.⁸ The key text is Article 47 paragraph 1 letter c, which punishes anyone who intentionally discloses to further persons, or exploits for himself or another, a secret that was disclosed to him in breach of letter a. The Federal Supreme Court quoted this new wording in the course of a judgment on the proceeds of a data sale that it delivered a few months before the revision took effect.⁹ Paragraph 1bis contains the aggravated offence with its five-year maximum. The current text also provides that the breach remains punishable after the end of the employment or professional relationship.¹⁰

Article 47 in the courts

Three decisions illustrate how the courts have applied the provision in the era of data leaks. The first concerns the sale of client data of a Swiss bank to the tax investigation office of Wuppertal. A bank employee had extracted the data and passed them to an accomplice, who sold them to the German authorities for about 2.5 million euros and died during the Swiss proceedings. The Federal Supreme Court upheld the forfeiture of the proceeds against his heirs. It held that the sale fulfilled the elements of qualified economic espionage under Article 273 of the Swiss Criminal Code, an abstract endangerment offence that protects Swiss territorial sovereignty and the national economy and does not require that any state or private interest was actually harmed.¹¹ The case shows that the prosecution of data sales does not rest on Article 47 alone. Economic espionage, a much older offence, reaches conduct that the banking secrecy provision in its old form did not.

The second decision concerned Rudolf Elmer, the former chief operating officer of the Cayman Islands subsidiary of the Zurich bank Julius Bär. After leaving the bank in 2003 Elmer had passed client data to the Swiss tax authorities, to WikiLeaks and to the media. In its judgment of 10 October 2018 the Federal Supreme Court held that Article 47 did not apply to him, because he had worked for a Cayman Islands institution that was not subject to Swiss banking law, even though it provided part of the wealth management services of a Swiss bank. He was convicted of other offences, including forgery and threats.¹² For the Zurich financial centre the ruling marked a territorial limit. Article 47 protects secrets entrusted to Swiss banks and their Swiss staff, and group structures that book client relationships abroad fall outside its protection unless the facts establish a Swiss banking capacity.

The third decision concerns the press. When an international network of journalists coordinated by the Süddeutsche Zeitung published data on some 18,000 accounts at Credit Suisse in February 2022 under the name “Suisse Secrets”, Swiss media declined to participate because of the risk of prosecution under letter c.¹³ The Federal Supreme Court later held, in a judgment of 12 December 2024, that the freedom of the press guaranteed by Article 10 of the European Convention on Human Rights could justify the conduct of journalists under the general justification of Article 14 of the Criminal Code. Following this ruling, the Zurich public prosecutor closed an investigation against the financial journalist Lukas Hässig, while the Geneva Attorney General Olivier Jornot dismissed proceedings against three Tamedia journalists in November 2025.¹⁴ The extension of 2015, designed to deter data traders, thus met its constitutional limit in the reporting of matters of public interest.

Notes

1. Paraphrase of the original Article 47 BankG (AS 51, p. 117), following the reproductions in the commentary literature. The original penalties were a fine of up to 20,000 francs or imprisonment of up to six months, or both. ↩
2. Matthias Michlig, “Bankgeheimnisverletzung (Art. 47 BankG)”, Aktuelle Juristische Praxis (AJP/PJA) 8/2014, pp. 1055–1062, https://www.michligknutti.ch/05-aufsatz-bankgeheimnis-1-.pdf, quoting the dispatch of 1970: “Das Bankgeheimnis ergibt sich somit aus den allgemeinen Bestimmungen des Obligationenrechtes” (p. 1057). ↩
3. Art. 47 para. 5 BankG as reproduced in BGE 145 IV 114, https://entscheide.weblaw.ch/cache.php?link=BGE-145-IV-114&q=%22145+iv+114%22&sel_lang=de: “Vorbehalten bleiben die eidgenössischen und kantonalen Bestimmungen über die Zeugnispflicht und über die Auskunftspflicht gegenüber einer Behörde.” The same reservation stood in Art. 47 para. 4 of the version in force until 2008 (consolidated version of 27 December 2006 on LexFind, https://www.lexfind.ch/tolv/141673/de). ↩
4. Michlig, “Bankgeheimnisverletzung” (2014), pp. 1056–1058, on the history of the provision and the formulation of 1971. ↩
5. Federal Supreme Court, judgment of 10 October 2018, BGE 145 IV 114, headnote referring to “Art. 1 und Art. 47 (in den ab 1. Juli 2004 und ab 1. Januar 2009 geltenden Fassungen) BankG”, https://entscheide.weblaw.ch/cache.php?link=BGE-145-IV-114&q=%22145+iv+114%22&sel_lang=de. ↩
6. Federal Act on Banks and Savings Banks (SR 952.0), consolidated version of 1 January 2009 on LexFind, https://www.lexfind.ch/tolv/141675/de: Art. 47 “Fassung gemäss Anhang Ziff. 15 des Finanzmarktaufsichtsgesetzes vom 22. Juni 2007, in Kraft seit 1. Jan. 2009”, with a fine of up to 250,000 francs for negligent breach in para. 2. The version in force until 2008 provided for imprisonment of up to six months or a fine of up to 50,000 francs (consolidated version of 27 December 2006, https://www.lexfind.ch/tolv/141673/de). ↩
7. Schweizer Radio und Fernsehen (SRF), “Bankgeheimnis: Datenklau soll härter sanktioniert werden”, 16 September 2014, https://www.srf.ch/news/schweiz/schweiz-bankgeheimnis-datenklau-soll-haerter-sanktioniert-werden. ↩
8. David Zollinger, “Die Verwendung von Bankdaten durch Medienschaffende”, medialex, 8 July 2022, https://medialex.ch/2022/07/08/die-verwendung-von-bankdaten-durch-medienschaffende/, which contrasts the version in force before 1 July 2015 with the extended version. ↩
9. Federal Supreme Court, judgment 6B_508/2014 of 25 February 2015, https://entscheidsuche.ch/dok/CH_BGer/CH_BGer_006_6B-508-2014_2015-02-25.html, citing the new letter c: whoever intentionally “ein ihr oder ihm unter Verletzung von Buchstabe a offenbartes Geheimnis weiteren Personen offenbart oder für sich oder einen anderen ausnützt”. ↩
10. Art. 47 paras. 1bis and 4 BankG as reproduced in BGE 145 IV 114, https://entscheide.weblaw.ch/cache.php?link=BGE-145-IV-114&q=%22145+iv+114%22&sel_lang=de: para. 1bis punishes with a custodial sentence of up to five years whoever obtains a pecuniary advantage for himself or another through an act under para. 1 let. a or c, and para. 4 provides that the breach “ist auch nach Beendigung des amtlichen oder dienstlichen Verhältnisses oder der Berufsausübung strafbar”. ↩
11. Federal Supreme Court, judgment 6B_508/2014 of 25 February 2015 (see above), on forfeiture, Article 273 paragraph 2 of the Swiss Criminal Code and the principle of state protection under Article 4 of the Criminal Code. ↩
12. Federal Supreme Court, BGE 145 IV 114 of 10 October 2018 (see above), headnote and considerations on the subjection to banking secrecy of a person working for a foreign banking institution that provides part of the asset management services of a Swiss bank. ↩
13. Zollinger, “Die Verwendung von Bankdaten durch Medienschaffende”, medialex (2022). ↩
14. Simon Canonica, “Fehlkonstruktion Art. 47 Abs. 1 lit. c BankG: Hilfe kommt von unerwarteter Seite”, medialex, 6 February 2026, https://medialex.ch/2026/02/06/fehlkonstruktion-art-47-abs-1-lit-c-bankg-hilfe-kommt-von-unerwarteter-seite/, discussing judgment 6B_650/2022 of 12 December 2024. ↩

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.