SolvedCH122320 | Offshore matters: asset-based penalties: identification and valuation of assets: assets jointly held
From HM Revenue & Customs · Compliance Handbook
This section applies where an asset-based penalty is chargeable in relation to an asset that is jointly held by the taxpayer liable to the standard offshore penalty and another person or persons.
The value of the asset is to be taken to be the value of the taxpayer’s share of the asset.
In a situation where the owners of the asset are married to, or are civil partners of each other, and live together, the asset is to be taken as jointly owned by them in equal shares, unless it appears to HMRC that this is not the case.