3.—(1) Subject to regulation 4, no person shall compile, use, sell or supply a prohibited list.
(2) A “prohibited list” is a list which—
(a)contains details of persons who are or have been members of trade unions or persons who are taking part or have taken part in the activities of trade unions, and
(b)is compiled with a view to being used by employers or employment agencies for the purposes of discrimination in relation to recruitment or in relation to the treatment of workers.
(3) “Discrimination” means treating a person less favourably than another on grounds of trade union membership or trade union activities.
(4) In these Regulations references to membership of a trade union include references to—
(a)membership of a particular branch or section of a trade union, and
(b)membership of one of a number of particular branches or sections of a trade union;
and references to taking part in the activities of a trade union have a corresponding meaning.