Key legal question
Whether Thurgau may levy wealth and income tax on the warehouse-based business factor in Romanshorn.
Extracted holding
Yes. The business was an economic unit extending over both cantons; the warehouse was an essential operating factor, so Thurgau had taxing power.
Extracted reasoning
The court rejected both the branch-office theory and the notion of a fully independent local business. Tax jurisdiction was to be apportioned because a substantial part of the unitary enterprise operated in Thurgau.