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HMRC internal manual

Inheritance Tax Manual

Assessing: SAGE: forms

Some of the forms you will come across are

Cas10 For Accounts, Nottingham to advise you of cancelled receipts (IHTM31901)
Cas12 To transfer payments from one file/entry to another (IHTM31921)
Cas15 To match (IHTM31866) or unmatch payments
Cas16 To match payments to penalty charges