CG14780 | Assets disposed of: Series of transactions: liaison between districts
From HM Revenue & Customs · Capital Gains Manual
As we need to arrive at the same result for buyer and seller, it is important that you liaise with your counterpart. We would expect the Office dealing with the seller to take the lead in this and to seek to agree any apportionment with the seller or their agents. This applies even where the buyer's Office is dealing with a claim to Capital Allowances, see CG14790.
If you are unable to reach agreement with the seller on any apportionment, then the matter will need to be considered by the First-tier Tribunal or other appeal body, such as the Lands Tribunal. You should refer to the parts of the manual dealing with the asset(s) concerned for guidance on appeal procedures. For example:
If you have to take an apportionment to an appeal, then you should always link the other party to the appeal by using SI1967/149,.