OK, here are typical examples of 'no right answer' tax issues.
Suppose that a group of companies manufactures and sells widgets. The widgets are manufactured by a group company in Germany. There is a UK company which is responsible for selling widgets to customers in the UK and Ireland. How much should the UK company pay the German company for each widget it sells?
UK tax law doesn't care what price is actually agreed between the UK company and the German company. It simply says that for tax purposes the price should be the price that would have been charged between unrelated parties (that is, a selller and a buyer who are not under common control). This is often called the "arm's length price". If HMRC argues successfully that the price charged was not at arm's length then it can replaces the actual price with the arm's length price - for tax purposes only.
If the German company happens to also manufacture exactly the same type of widgets for sale to unrelated customers of its own then the arm's length price is relatively easy to determine - Germany should sell the widgets to its UK sister company at the same price as it sells them to its own customers (there are, actually, reasons why the sales price might differ, such as bulk purchase discounts, but let's keep it straightforward for now).
But in reality it's extremely unusual for the German company to also sell direct to third party customers. So the obvious answer isn't available. What happens next?
The OECD says that the next best thing is to use statistical analysis of published economic data for millions of sales transactions to calculate what the arm's length price. And economists have done enormous statistical studies attempting to do just that. It's an absolute balls ache to grind through the numbers, and it's far from easy to agree which transactions are even sufficiently comparable that they should be included in the number-crunching to start with. But the consensus is that there is a very strong link between the costs that manufacturing companies incur and the prices that they charge.
So the price the German company should charge the UK company should be based on its costs plus a mark up for its profits. In other words, if it incurs costs of 100 to manufacture each widget then it should charge 100 plus a profit margin.
(Note here that the price that the widgets are to be sold by Germany to the UK is entirely dependent on the costs incurred in Germany. There is no allowance to be made for the price that the UK company can sell the widgets on to its customers.)
Ah, but what should the profit margin be?
It depends on the risks that the German company takes on to operate its business. The more risks it takes, the more profit it should make.
The group as a whole can decide which risks will be borne by the German company and which by the UK company. Let me give you some examples:
- Who will decide how many widgets the factory will manufacture each month? If the German factory can be left with unsold widgets at the end of the month then it's bearing more risk than if the UK company is obliged to buy all the widgets as a matter of course.
- Who decides where the factory gets its raw materials? Often, a central purchasing team will negotiate global contracts for raw materials, in which case the German company doesn't have to worry about suppliers going bust or trying to renegotiate prices.
- Who owns the patents for the technology which the German company uses to make its widgets? Again, it's common for groups to have a centralised R&D team that come up with all of the clever technology, so the German company doesn't need to.
- What happens if a UK customer makes a complaint about a widget? Does the UK company have automatic right of recourse against Germany or not?
- Who has to insure the widgets when they're shipped from Germany to the UK?
- Will Germany sell its widgets to the UK in Euros, or pounds Sterling? That will determine which of the two bears foreign exchange risk.
So once all the risks have been allocated out, the group will try and calculate what the German company's profit margin should be. A low-tech low risk factory might only earn a profit margin of, say, 5%. (That is, if it incurs costs of 100 it will sell its widgets to the UK company at a price of 105.) A high-tech high risk factory might ean a profit margin of, say 25%.
So now imagine that the group does all of the statistical and risk analysis, and concludes that the price that Germany should charge the UK is cost + 10%.
HMRC does not agree. It says the price is too high and should only have been cost + 8%.
The German tax authorities also disagree. They think the price was too low, and should have been cost + 12%.
Who is right? Nobody knows. Everyone has to argue the toss between them and try to find a solution that they can all live with.
Now imagine that R&D centres are in the US and Asia-Pac, the raw materials suppliers are also group companies, that the widgets manufactured in Germany have to be packaged in each sales jurisdiction to meet marketing authorisation requirements, the group operating its back office functions out of a data centre in Belgium, and its distribution functions out of a warehouse in the Netherlands. Imagine the complexity then
Welcome to the wonderful world of transfer pricing....