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HMRC internal manual

Capital Gains Manual

Debt on security: when conditions satisfied: changes in terms

You should not accept that a debt can be regarded as the debt on a security because the terms of the loan could have been amended to make the debt marketable. If the terms of the debt have changed this cannot affect the status and tax treatment of the debt prior to the changes. You may, however, need to consider whether or not the changes had the effect of bringing to an end the original debt, and creating a new one, to which a different tax treatment may apply.