The SPF approach in relation to trading profits and non-trade finance profits effectively applies a test of substance or relevant activity at an asset or risk level, which can be seen as a measure of relevant economic susbtance and activity. In addition, the rules apply a business premises condition in relation to trading profits and intra-group non-trading finance profits, which have to be occupied with a degree of permanence and from where the business of the CFC has to be carried on. For completeness, other exemptions include : Tax rate exemption - where the local tax paid is at least 75% of the tax that would have been paid in the UK.    De minimis threshold - less than £50k profits in a 12 month period, or less than £500k profits so long as passive interest income does not exceed £50k in that period.    Low profit margin exemption - where accounting profits are not more than 10% of relevant operating expenses.    Excluded countries list based on regimes with similar tax rules to UK, subject to an anti-avoidance test and limits on passive income.    Temporary exemption period for certain acquisitions, subject to anti-avoidance conditions.    Partial and full exemption for certain types of intra-group finance profits, subject to detailed anti-avoidance conditions.    Exemption for certain trading profits where a minority of significant people functions are carried out in the UK.