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HMRC internal manual

Compliance Handbook

Penalties for inaccuracies: other penalty issues: company and company officer penalties: What is a company

You must check the date from which these rules apply for the tax or duty you are dealing with. See CH81011 for full details.

For the purposes of determining an officers liability for company penalties ‘company’ means

…any body corporate or unincorporated association, but does not include a partnership, a local authority or a local authority association.