What are the GloBE rules and what is their legal status?
They are model rules: an agreed text setting out how the global minimum tax is computed and collected, with no direct legal force of its own. A country gives them effect by enacting them into domestic law, and until it does, nothing in the model binds a taxpayer there. The distinction matters in practice for two reasons. Your obligations are read from the local statute rather than from the model, and commencement dates differ between countries, so a group can be inside the rules for one of its jurisdictions and not yet for another in the same year. The model is the common reference; the enactments are the law.
How does the income inclusion mechanism work?
It works upwards through the ownership chain. Where profit in a jurisdiction has borne less than the minimum, the shortfall is collected as a top-up charged on an entity higher up the group — typically a parent — in respect of the low-taxed profit of the entities beneath it. So the charge does not necessarily arise where the profit arose, and the payer may sit in a country whose own tax was never in question. Two consequences follow: the parent's jurisdiction needs figures about subsidiaries it does not file for, and the group must work out ownership interests and chains carefully, because the shortfall is apportioned along them.
What is the undertaxed payments mechanism for?
It is the backstop. The income inclusion mechanism collects a top-up from a parent, but only where some jurisdiction in the chain above the low-taxed profit has enacted it. Where none has, the undertaxed payments mechanism lets other jurisdictions in which the group operates collect the shortfall instead, typically by denying deductions or making an equivalent adjustment. Its purpose is to leave no low-taxed profit uncollected, wherever the group's parent happens to sit. For a group this means a country with no connection to the low-taxed profit at all can end up making the adjustment, which is why scoping covers every jurisdiction the group is in.
Which rule applies first if two countries could charge us?
There is an order and it runs top down. The income inclusion mechanism has priority, so a top-up is collected first from the highest entity in the chain whose jurisdiction has enacted it, and the undertaxed payments mechanism applies only to what is left over. A local top-up charge in the jurisdiction where the low-taxed profit arose can come ahead of both, keeping the amount there. The reason to work the order out before computing anything is that it determines which of your countries need a filing and which merely need to supply data. Groups that compute first and ask who pays afterwards generally redo the work.
Do the GloBE rules apply the same way in every country?
No, and that is the main trap. The model text is common, but each country enacts its own version, on its own commencement date, sometimes with drafting differences and sometimes with a local top-up charge alongside. The same group fact pattern can therefore produce a filing in one country a year before another, and the definitions applied to a particular item can differ at the margins between two enacting states. The working method is to compute on the model as the common basis and then check each obligation against the local statute that creates it. Treating one country's legislation as the group's rulebook is how deadlines get missed.
Are the GloBE rules the same thing as Pillar Two?
They describe the same project from different angles, and it is worth keeping them apart when you read. Pillar Two is the policy: a minimum level of tax tested jurisdiction by jurisdiction. The GloBE rules are the operative text implementing it — the definitions, the effective rate computation, and the two collection mechanisms, income inclusion and undertaxed payments. In conversation the terms are used interchangeably; in a file they should not be, because whether you are in scope is answered from the policy's size test, while who pays what is answered from the operative rules and from the local enactment of them.
What is double tax relief and how is it given?
Three mechanisms, and which one you get depends on your residence country's law and the treaty. Exemption leaves the foreign income out of the residence-country base. Credit taxes it and then subtracts the foreign tax, capped at the residence-country tax on that income. Deduction merely reduces taxable income by the foreign tax, and is usually the weakest. Canada and the United States lead with credit; several treaties give exemption for specific income types. See claiming the credit.
Branch or subsidiary — which should we use to expand?
A branch keeps one taxpayer: results consolidate at home, losses are usable sooner, and the exposure is that the branch is a permanent establishment whose profit the host country taxes, sometimes with a branch tax on repatriation. A subsidiary is a separate taxpayer with limited liability and local rates, at the cost of withholding on dividends home and transfer pricing on everything between them. The deciding facts are usually expected losses, liability and exit plans. See branch against subsidiary.
