Overview of the Swiss Federal Supreme Court’s tax law decisions published between September 28 and October 4, 2026:
- Judgment of August 28, 2026 (9C_604/2025): Federal Direct Tax and State and Municipal Taxes for 2022 (Thurgau); In the present case, the Federal Supreme Court had to determine whether the tax administration of the Canton of Thurgau had correctly classified various invoices recorded as expenses in the 2022 tax period as non-business-related expenses. The taxpayer, a limited liability company (GmbH), argued that the invoices in question represented business expenses that had actually been incurred and were therefore tax-deductible. The Federal Supreme Court upheld the lower court’s ruling. In particular, it considered the general nature of the invoices, the absence of detailed work reports, conspicuous similarities between invoices from different companies, and unusual cash payments to be strong evidence against the validity of the claimed expenses. Since the taxpayer was unable to prove that the invoices were based on services actually rendered, the Federal Supreme Court upheld the set-offs. The taxpayer’s appeal was dismissed.
- Judgment of September 7, 2026 (9C_88/2026): State and Municipal Taxes 2010–2015 (Geneva); Intercantonal Double Taxation; The issue at issue in this case is whether the Canton of Geneva has forfeited its right to tax. The same facts had already formed the basis for the judgments 9C_393/2025 (see our article on the judgment of February 24, 2026) and 9F_10/2026 (see our article on the judgment of June 12, 2026) concerning the 2016 tax period. The taxpayer company, headquartered in the Canton of Schwyz, was presumed to have limited tax liability in the Canton of Geneva. The Canton of Geneva had been aware of the facts relevant to taxation at the latest as of the audit report dated February 6, 2018, but did not initiate the corresponding back-tax proceedings until November 26, 2020. According to the case law of the Federal Supreme Court, in cases of intercantonal double taxation, a canton forfeits its tax claim if it (1) was aware of the facts relevant to taxation, (2) nevertheless waited too long to assert its tax claim, and (3) this delay results in another canton having to refund a tax that it had levied properly, in good faith, and without knowledge of the competing tax claim. In the present case, the Federal Supreme Court considered the delay of more than two and a half years to be too long. Consequently, the Canton of Geneva has forfeited its tax claim for the tax periods 2011–2015; the tax period 2010 was already absolutely time-barred. The penalties for the tax periods 2013–2015 were also to be set aside. The taxpayers’ appeal was granted.
Non-occurrence / write-off:
Decisions are listed chronologically by publication date.
