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HMRC internal manual

Capital Gains Manual

Separate settlements: appointment or advancement by trustees

Otherwise you should ask whether the trustees consider that a new settlement has been created, for Capital Gains Tax purposes, and to give their reasons for their view. You should obtain from them the original settlement deed, if you do not have it already, the Deed of Appointment or Advancement, and any other relevant document, and consider the case in the light of the principles in CG37840 - CG37844.