The taxpayer, who was resident in the UK, paid US income taxes on his share of the profits of an LLC of which he was a member, and also paid UK income taxes on income remitted to the UK including such share of the LLC's profits. He would have been entitled to relief under Art. 23 of the UK-US Double Tax Convention from UK tax on such profits if the UK tax was "computed by reference to the same profits or income by reference to which the United States tax [was] computed."
In finding that this requirement was not satisfied, given that the distribution of the profits to the taxpayer (so as to attract UK tax) was distinct from the earning of the profits by the LLC in the first place (resulting in the US tax), i.e., the LLC was fiscally transparent for US but not UK purposes, Lady Justice Arden stated (at para. 57):
If profit is earned by an entity, and the source of the profit to the taxpayer as a member of that entity is a contract as between him and other members, then in the usual case it follows that the source of his income must be a different source of income from that of the entity itself. The fact that there is a contract generally suggests that there is a disposition of a right to the profits from one person to another. That result can be avoided if the member had a proprietary right to the profits as they arose. This would as I see it generally be the case where income accrues to a trust under which an income beneficiary has an interest in possession, or to a unit trust or collective investment scheme, if the investors have a beneficial interest in the assets that are subject to the unit trust or scheme.
In the case of the LLC, there was was "nothing to suggest that it did not have unqualified ownership of its assets or that its members had any interest in those assets" (para. 77). She furher stated (at para. 64):
It would be unusual but not impossible for an entity with a separate legal personality, such as a company, to be tax transparent for English law purposes. One example would be the Scottish partnership where the partnership is a separate legal entity and holds the assets of the business, but the partners have an (indirect) interest in the assets and carry on business in common: this has been held by this court to be tax transparent....