The latest judgment from the Court of Appeal on Marks & Spencer is, I think, more significant than some are suggesting.

Jonathan Bridges of KPMG said it was 'good news but not huge news for M&S and other taxpayers,' but, though I can't claim the raft of qualifications he can, I think I disagree.

The case, you'll remember, is about losses incurred in EU subsidiaries which M&S, and other companies, want to set off against UK profits.

The nub of the current argument is a ruling by the ECJ that such losses could be offset where opportunities for relief in the other EU countries had been 'exhausted.' (or, in an alternative formulation, where there was 'no possibility' for the losses to be relieved).

That left the field wide open for the most extraordinary interpretations of 'exhausted'. Does that mean that if, in future years, you could use them, you would have to wait until those possibilities expired? Was it a theoretical or factual offset you were talking about (in that the opportunity could exist in tax law, but you might not have factual profits in the EU sub to offset against).

The government weighed in in the 2006 Budget with a further point; that you could only claim a loss that could be claimed in the UK under UK accounting and tax rules, and that at the same time, you could only claim an amount that you could have claimed elsewhere. The loss would have to be whichever was lower: the UK or foreign loss.

The Court of Appeal judgment seems refreshingly straightforward.

Paragraph 49 says that there must be 'no real possibility' of relieving the losses elsewhere, which, though sounding similar, takes a lot of the theoretical sting out of the original ECJ judgment. You don't have to think about parallel universes in which your company realises huge profits in ten years time that you didn't predict, and could have offset the losses against. You just have to think of a 'real possiblity' in the here and now.

The judgment goes on: 'a real possibility is one which cannot be dismissed as fanciful.'

I think this adds a lot of clarity (though advisers and inspectors will likely argue it further), and I think that that is signficant both because it helps to resolve this argument, and also because where EU tax arguments are concerned, clarity is such a rare commodity.

A judgment that is not only helpful to the taxpayer, but comprehensible to the taxpayer. A huge win.