Art. 51 Federal Law of 13 October 1965 on Withholding Tax (WTA)
Art. 51 LIA
If the Federal Tax Administration (FTA) rejects the request in whole or in part, it issues a decision, unless the dispute can be resolved in another manner.
Any refund that is not based on a decision according to para. 1 is made subject to subsequent verification of the right to said refund; after a period of three years from the refund, such verification can only be carried out in connection with a criminal procedure.
If the verification reveals that the refund was wrongly granted and if the applicant, their heirs, or the jointly liable persons refuse to return the amount, the FTA issues a decision demanding restitution.
Articles 42 to 44 concerning the procedure for claims and appeals and the procedural costs, as well as, in the case of para. 3, Articles 45 and 47 concerning enforcement and securities, apply by analogy.