TSEM6235 | Legal background to trusts & estates: what a trust needs
From HM Revenue & Customs · Trusts, Settlements and Estates Manual
A trust needs a
settlor
corpus (trust fund) - the settled property
beneficiary
trustee.
It also needs certainties of
words - a clear indication that a trust is being set up
subject matter - the property that has been settled
object - who is the beneficiary.
If the trust does not contain these three certainties, it is invalid. The transferred property is held on a resulting trust for the settlor.