IHTM25302 | The ownership test: Meaning of ownership
From HM Revenue & Customs · Inheritance Tax Manual
For the purposes of the ownership test () (including the three situations where the general rule is relaxed) we consider ownership to have the following meaning
in the case of settled property in which there is no qualifying interest in possession, legal ownership by the trustees,
in all other cases, beneficial entitlement (), which includes entitlement to settled property in which the deceased/transferor had a qualifying beneficial interest in possession ().
In view of , where an unadministered residuary estate () includes business property, a residuary beneficiary is treated as owning the business property, or an appropriate share of it.