INTM331021 | Double Taxation applications and claims: Repayment claims from non-residents: Completion of enquiry into claim
From HM Revenue & Customs · International Manual
When you have received all the information you need and have decided whether you can accept the claim or need to amend it you must send a closure notice to the claimant informing him that you have completed your enquiries and stating your conclusions.
For full guidance on how to complete enquiries into a claim see INTM331300.