IHTM33046 - Loss on sale of land: procedures: notifying tax offices of revised values
If you receive a claim for loss on sale of land relief more than three years after the date of death you should, once the relief has been agreed, refer the case to the Liaison contact point in the IHT Risk team for them to complete a report for the deceased’s tax office. Your reference should list the revised values of all items of property covered by the claim.
You should also send the tax office information about a claim made within three years of the death if they ask you to do so. If no claim has been made within three years you should make a note to inform the tax office of any subsequent claim received even if it was made less than four years after the death.