CG68320 - Goodwill and Intellectual Property Rights: post transaction valuation checks
Shares and assets valuations for tax (GOV.UK) gives guidance on obtaining post transaction valuation checks (PTVC).
If you receive a PTVC request for a valuation of an intangible asset you should deal with it in accordance with the guidance at CG68300.
You should inform Shares and Assets Valuation that the valuation is needed for a PTVC and supply a copy of the computation of the gain or loss and any other information that has been provided in support of the request.
CG16611+ explains the action that you should take when you receive the return for the tax year in which the transaction took place.