When infra-state bodies enjoy a certain fiscal autonomy, issues of double taxation inevitably arise. In its decision of 23 March 2011, 2011/17/0045, the Austrian Supreme Administrative Court was called upon to answer the question whether the municipality of Vienna is entitled to levy a tax on gambling machines put up and played within its boundaries, even though the related data processor is located in Styria. The reasoning of the Austrian Supreme Administrative Court is focused on the “genuine link” principle according to which the taxation of foreign economic transactions is permitted when a sufficient connection exists between the taxpayer and the taxing states. However, the Court also referred to a 1998 decision of the Austrian Constitutional Court, in which in the context of the limitation of federal tax competences a more complex approach was adopted, linking principles of international tax law with constitutional requirements. This contribution reflects the dogmatic background and justification of this approach and questions whether its application in the case at hand is fruitful.