1. The STTR restores to the source State a limited taxing right, or in some cases supplements an existing limited taxing right retained by the source State, and operates as a derogation from the other provisions of the Convention that would otherwise restrict the source State’s right to tax. This creates an interaction between the STTR and the elimination of double taxation provisions contained in tax treaties.
2. For example, under paragraph 1 of Article 23 A of the OECD Model, the residence State is obliged to exempt an item of income where the source State is permitted to tax that item of income in accordance with the treaty. Where the conditions are met for the STTR to apply, the source State will be permitted, in accordance with the treaty, to apply additional tax and the residence State will then be obliged under the provisions of the elimination article to exempt that income from tax. Even where that obligation is not taken into account for the purposes of determining the adjusted nominal rate, and therefore does not increase the additional tax that can be applied in the source State, the residence State will nevertheless be deprived of its taxing right. The result of this will be that only the source State will tax the affected payment; and only at the specified rate.
3. Similar considerations arise where the residence State is obliged to provide a credit under paragraph 1 of Article 23 B or paragraph 2 of Article 23 A of the OECD Model. Even though that credit is not taken into account in computing the adjusted nominal rate for the purposes of the STTR (according to subdivision (i) of subparagraph b) of paragraph 6), the residence State’s taxing right is reduced by the credit it is obliged to give for the additional tax applied in the source State.
4. These considerations are relevant where the application of the STTR would result in a new or greater obligation being imposed on the residence State under provisions based on Article 23 A or 23 B.
5. As a general rule, the approach taken in this report preserves the position that would have applied before the STTR comes into play and makes adjustments to the operation of the treaty elimination provisions in respect of an additional obligation that would otherwise be imposed on the residence State as a result of the source State taxing covered income at the specified rate. This avoids an unintended reallocation of taxing rights away from the residence State.
6. This approach sets limits on the obligations imposed on the residence State under the elimination of double taxation provisions of treaties based on the Convention, but it does not govern or disturb other mechanisms that may apply outside the treaty to mitigate or eliminate double taxation. For example, a residence State may, under its domestic law, provide unilateral credit relief for the additional tax imposed as a result of the source State taxing covered income at the specified rate under the STTR, or it may provide relief for the tax paid to the source State by way of a deduction.
7. Neither does the approach taken in this report regulate or alter the treatment, for the purposes of applying the IIR and UTPR, of tax paid as a result of the operation of the STTR. Tax paid as a result of the operation of the STTR is, as a tax in lieu of generally applicable income tax, a covered tax for the purposes of the IIR and UTPR; and is allocated and accounted for in the ETR computation required under the GloBE rules.
8. Therefore, the only adjustments made to Articles 23 A and 23 B are to add a sentence that would disapply the exemption method in cases where it would not have applied in the absence of the STTR, and a sentence that would disallow a foreign tax credit for the tax paid under the STTR. These outcomes permit the source State to apply tax at the specified rate in accordance with the STTR, without this resulting in a reallocation of taxing rights away from the residence State that would arise solely as a result of the operation of the STTR. Given that the STTR only applies where covered income is subject to a rate of tax below 9% in the residence State, applied to a measure of net income, and that the STTR results in the source State being permitted to tax the gross amount of the covered income up to the specified rate, the residence State’s capacity to provide additional relief may in many cases already be limited or exhausted.