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HMRC internal manual

Capital Gains Manual

Share exchange: effect of TCGA92/S135: different classes of shares

Unquoted shares

If the acquiring company issues different classes of share or debenture it may be necessary to apportion the base cost of the new holding between its different components. The main rule in TCGA92/S129 is that the apportionment is made by reference to the market value of the different shares and debentures at the date of disposal, see CG51892.

Quoted shares

However, TCGA92/S130 will apply if one of the different classes of share or debenture is quoted within three months of the takeover or such later time as the Board may allow, see CG51965. In this case you make the apportionment by reference to market value on the first day on which the new shares or debentures are quoted. For full instructions see CG51965+.