SIOG7260 | Information and inspection powers: Schedule 36 FA 2008: records to be kept
From HM Revenue & Customs · Specialist Investigations Operational Guidance
A copy of all formal notices issued under Schedule 36 FA 2008 should be kept by the Team Leader in an establishment file. A record should also be kept in that file of cases where:
the person to whom the notice was sent was not given an opportunity letter (paragraph 3(2)(c))
reasons for the notice were not given to the taxpayer (paragraph 3(2)(e))
a copy of a third party notice is not provided to the taxpayer (paragraph 4).