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HMRC internal manual

Capital Gains Manual

Assets disposed of: series of transactions: problems

While a market value based approach is often the best way to go about an apportionment, you need to be aware that it is not infallible and may in certain circumstances be only a guide to an answer, not the complete answer.

The rules for arriving at the market value of an asset assume that it is put on the open market and sold in a bargain between a willing buyer and a willing seller. However, in real life, you can strike a bad bargain as well as a good one. If, therefore, the actual seller has been badly advised or is a bad negotiator, they may genuinely have sold assets for a total sum which is less than their total worth. That, in itself, does not allow us to replace the actual sale proceeds by the full market value. If the parties are unconnected and entered into a bargain at arm’s length, see CG14540, we cannot introduce market value.

If you are using market values to arrive at an apportionment, you cannot, in the circumstances just outlined, increase the actual total sale consideration. You may still be able to use the individual market values of the various assets as a starting point for dividing that total consideration on, for example, a pro-rate basis.