IHTM15022 | Investigation of form IHT404: what information does form IHT404 contain?
From HM Revenue & Customs · Inheritance Tax Manual
Form IHT404 asks for the following information for each jointly held asset
a description of the asset
who the joint owner(s) (other than the deceased) were
when the joint ownership began
how much each joint owner provided to obtain the property
who received any income or interest generated by the property
the value of the whole item and the value of the deceased’s share of it.
details of any liabilities that are to be deducted
details of any exemptions that are due.