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HMRC internal manual

Oil Taxation Manual

Decommissioning and abandonment: decommissioning security agreements: tax treatment of sums paid out to meet the costs of decommissioning

Relief for decommissioning costs will be due to the company when decommissioning costs are met from monies held by the trust.

The reasoning is that, as a matter of tax law, there is no out and out alienation of the monies paid into the fund as the company has a continuing beneficial interest in the fund.