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HMRC internal manual

Capital Gains Manual

Deferred consideration: shares/securities: position before TCGA92 S138A - ESC D27

The treatment is different if the new debentures are QCBs. In this case the exchange of the notional security for the QCBs triggers the operation of TCGA92/S116. You compute the gain that would have arisen on a deemed disposal of the notional security. That gain is then released on a disposal of the QCB. For further details see CG58070+.