Re: @Pellinor Ninja Accountants
@ frank ly: I read the article, and your comment, carefully.
You say that in the total company books (by which I assume you mean the consolidated accounts) the expense would be £1, because there'd be expenses of £1.50 (presumably 50p in the US and £1 in the UK) and income of 50p. That is of course bollocks, to use the technical term, as the £1 cost in the UK would be £1 of income in the US. You've confused yourself with the 50p profit you mentioned earlier.
The article is doing this to illustrate transfer pricing, suggesting that a 100% markup might be applied even though it's a bit steep, and thus save UK tax because the UK's £1 expense is too high: if UK tax rates are higher, then saving tax on £1 in the UK is worth paying tax on £1 in the US. That's basic transfer pricing.
What you've done is suggest that transfer pricing can somehow generate expenses out of thin air: the 50p actual cost has magically turned into £1 of tax deduction. That doesn't happen: all you can do with transfer pricing is shift profits around a group. You mention other "buying expenses", but again, you can't magic them out of nothing without having some profits arise elsewhere.
Except of course HMRC is very hot on such things and would come down like a ton of bricks on anyone who tries a 100% mark-up on low-value high-volume goods, and extra fees for no good reason. It's one of their big earners: they don't bother checking every year, they just come along every five years or so, and if they're not happy with the intra-group prices they reopen earlier years and charge penalties and interest on the extra tax.
Or at least, that's what's happened in my 15 years as a Chartered Tax Advisor advising international groups on corporation tax, transfer pricing, IP, and financing. Every group I've come across has been very nervous of HMRC or the IRS coming along, and taken pains to use reasonable prices. Top end of the "reasonable" range, maybe, but with a tax provision held back in case HMRC challenge them.
Perhaps my experience is untypical - what's yours been like?