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HMRC internal manual

Technical Teams Operational Guidance

Case review and registration: developing the review: fragmentation

Parties whose tax affairs are affected by the same facts or circumstances should, where possible, be worked in tandem. For instance, business partners, close companies and their directors should normally be worked together. In Code 9 cases it is particularly important to follow this model.

Each party to the investigation will require a separate caseflow record to be maintained. Cases which are part of a marketed Avoidance Scheme may be part of a single registration dealt with by the Counter Avoidance Directorate, see TTOG10045 for more guidance on Avoidance Schemes.