8(1)For the purposes of paragraph 7(2)(b) employers are associated if on the date which is the relevant date in relation to any of the payments or other benefits—
(a)one of them is under the control of the other, or
(b)one of them is under the control of a third person who controls or is under the control of the other on that or any other such date.
(2)In sub-paragraph (1)—
(a)“control” has the meaning given by section 840, and
(b)references to an employer, or to a person controlling or controlled by an employer, include the successors of the employer or person.