"Do you not agree that the Legal Estate can only be held in equal undivided shares? If so, unequal shares must be as tenants in common? In TSEM9814, HMRC state that s 836 also applies to unequal shares - which cannot be the joint Legal Estate?"
My first question is rhetorical in that I know the answer is Yes.
Agreed.
Surely the answer to the second question is also Yes?
It is not possible to hold the legal estate unequally; it cannot be held as tenants in common.
Likewise it must be Yes to question 3.
When HMRC say s 836 applies to shares held unequally they mean that under s 836 where legal title is held in the name of both spouses but they have declared they hold their beneficial interests unequally (which must mean as tenants in common) the income split is nevertheless for income tax purposes still split 50/50 ie not in line with their actual beneficial interests. For income tax to apply other than 50/50 then requires the election under s 837 (ie Form 17).
I am not saying I am correct, merely that HMRC agree with me. The requirement to disapply section 836 applies to UNEQUAL SHARES also, and only Form 17 can do this - TSEM 9814.
However, if legal title is held in one spouse name only then s 836 not in point; Form 17 then not in point. A simple declaration of trust then enables income tax to be levied as per the split contained in the declaration (and no Form 17 necessary).