Sch 11A para 4
(1) If it appears to the Treasury that a provision of a particular description is, or is likely to be, included in or associated with schemes that are entered into for the purpose of enabling any person to obtain a tax advantage, the Treasury may by order designate that provision for the purposes of this paragraph. (2) A provision may be designated under this paragraph even though it also appears to the Treasury that the provision is, or is likely to be, included in or associated with schemes that are not entered into for the purpose of obtaining a tax advantage. (3) In this paragraph “ provision ” includes any agreement, transaction, act or course of conduct.