The case
Administrative assistance (DTA CH–US); group request: The IRS requested that a bank provide an unredacted version of a Swiss bank’s II.D.2 report listing accounts with a presumed US nexus lacking proof of US tax compliance.
The Federal Administrative Court (FAC) had denied administrative assistance on the grounds that, in the absence of a specifically identified US person, the “foreseeable relevance” requirement under Art. 4 para. 3 TAAA could not be assessed.
By contrast, the Federal Supreme Court (FSC) stated that the request constituted a permissible group request, i.e. that bank account numbers qualify as sufficient identifying elements within the meaning of para. 10(a)(i) of the relevant protocol. For this reason, administrative assistance may not be refused solely because no affected person is identified by name at the time of the final decision. What is decisive is the plausible US nexus of the accounts concerned and the foreseeable relevance of the requested information regarding the account holders and beneficial owners.
The FSC accordingly upheld the FTA’s appeal.
Source: Decision of 19. March 2026 – 2C_234/2025
The commentary
The Federal Supreme Court’s expansive approach to international administrative assistance has been well established, entailing that the incremental insight offered by this decision is limited.
What has to be mentioned is the fact that the bank appears to have maintained an internal list of clients who, based on defined criteria, were considered to have a certain US nexus but lacked documented evidence of US tax compliance. This internal list itself became the object of the administrative assistance request.
Against this backdrop, a broader question arises as to how Swiss financial institutions are to design and implement robust client onboarding processes in compliance with KYC and AML requirements, if such internal risk classifications can be subject to disclosure to foreign authorities. This development highlights a potential tension between regulatory due diligence obligations and the protection of sensitive internal assessments.
