349.This Part is concerned with persons who intend to acquire control over UK authorised persons by virtue of their shareholding or voting rights.  The Part also deals with increases and decreases in the extent of a person’s control.  Specifically, a person who proposes either to acquire control or to increase the level of their control must notify the Authority and secure its approval.  The Authority may object to a particular acquisition or increase in control or it may attach certain conditions to its approval.  A person proposing to decrease their control must merely notify the Authority of their intention.  A breach of the obligations imposed by this Part is a criminal offence.  The requirements in this Part are necessary to meet certain single market directive obligations.  They carry forward similar requirements in the predecessor legislation.  For consistency, the requirements have been extended to cover controllers of all authorised persons incorporated in or formed under the law of any part of the United Kingdom and not just those persons which are included in the scope of the single market directives.  This Part does not place notification requirements on persons who exercise control over authorised persons by virtue of their position in that firm or in a parent firm, for example as a director or chief executive.  Such people may, however, need to be approved by the Authority under Part V of the Act.
Commentary on Sections Part Xii: Control Over Authorised Persons