It is trite law that the Hong Kong courts will not enforce a foreign arbitral award if it amounts to indirect enforcement of foreign laws. In the context of tax law, a defence known as the 'tax gathering' defence exists, under which a foreign award will not be enforced if it would, in effect, help foreign states to collect taxes. However, the requirements of this defence have been unclear. Now, a recent case has affirmed that an unsatisfied tax claim is a prerequisite for the tax gathering defence.