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HMRC internal manual

Inheritance Tax Manual

Negligence: who must you show to be negligent?

To establish a penalty for negligence under IHTA84/S247 (1) for delivering an incorrect account, information or document (IHTM36103) you must show that the taxpayer, the person who is responsible for delivering the account, was negligent. If there is more than one accountable person acting you should investigate the degree of culpability of each person in the event that proceedings are commenced against them in the absence of a negotiated settlement. In attempting to reach a negotiated settlement however you should seek a single penalty and not attempt to apportion it between the accountable persons. In any case of doubt or difficulty refer to the Penalty Portfolio Holder

You cannot automatically attribute an agent’s negligence to a taxpayer. But you do need to carefully investigate claims that the omission or error was the result of an agent’s failure (IHTM36315).

There is a separate penalty provision that applies where someone other then the taxpayer (IHTM36104) fraudulently or negligently provides incorrect information or an incorrect document, IHTA84/S247 (3).