SolvedOT66070 | Transferable tax history - TTH allocation on a loss carry back - Closing balance of the total TTH amount
From HM Revenue & Customs · Oil Taxation Manual
The closing balance of the total TTH amount is the total TTH amount that was acquired in the original TTH transaction, as reduced by the amount of any decommissioning losses that have been set against activated TTH in accordance with FA19\Sch15\Para25.