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HMRC internal manual

Capital Gains Manual

Share reorganisations: apportionment of cost: general

The normal part disposal formula in TCGA92/S42 does not apply to the apportionment of the cost of shares in a new holding. Instead you must use the formulae set out in TCGA92/S129 and TCGA92/S130. In practice there is unlikely to be much difference between an apportionment using Section 42 and an apportionment using Sections 129 and 130. Indeed in many cases the figures will be exactly the same. The crucial feature of Sections 129 and 130 is not the method of apportionment but the time at which you make the apportionment.