IHTM40012 | Clearance certificates: who is covered by a clearance certificate?
From HM Revenue & Customs · Inheritance Tax Manual
The form IHT30 protects all liable persons (IHTM30011)
at the same title
on the same occasion
for the tax on the property specified in the certificate
even though the form may not have been signed (IHTM40071) by all of them.
A certificate given to, say, the trustees (IHTM16050) of a settlement will not protect the deceased’s personal representatives (IHTM05012). Similarly a certificate given to the personal representatives will not protect the settlement’s trustees. If there is more than one title a separate application must be made at each title. This applies even if the personal representatives and the trustees are the same people.