4. After sub-paragraph (3) of paragraph 18 of Schedule 1 to the Act (groups and joint enterprises) there shall be inserted the following—
“(3A) Paragraph 13A above does not apply to a service which a person provides or offers or agrees to provide or to arrangements which a person makes or offers or agrees to make for the provision of a service if—
(a)that person is a body corporate and the service is or is to be provided to a body corporate in the same group and relates or will relate to assets which belong to that other body corporate; or
(b)that person is or proposes to become a participator in a joint enterprise and the assets to which the service relates or will relate are or are to be held on behalf of another person who is or proposes to become a participator in the enterprise and are or are to be held for the purposes of or in connection with the enterprise.”.