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HMRC internal manual

Capital Gains Manual

Gains on assets held on entry into a group: pooled or merged assets

The legislation does not prescribe any apportionment method. You can accept any reasonable method of apportionment consistent with the result that pre-entry losses are only set off against gains attributable to the increase in value up to the time of the disposal of that part of the gain asset held at the relevant time see CG47567.

Note: Additional rules relating to loss buying were enacted in FA 2006. See CG47020+ for guidance on the rules which apply in priority to TCGA92/SCH7A for accounting periods ending on or after 5 December 2005.

FA11/S46 and FA11/SCH11 greatly simplified the rules in TCGA92/SCH7A for the deduction of losses on or after 19 July 2011. See CG47400+ for guidance on loss streaming from that date.