40Employees and applicants: harassmentE+W+S
(1)An employer (A) must not, in relation to employment by A, harass a person (B)—
(a)who is an employee of A's;
(b)who has applied to A for employment.
(2)The circumstances in which A is to be treated as harassing B under subsection (1) include those where—
(a)a third party harasses B in the course of B's employment, and
(b)A failed to take such steps as would have been reasonably practicable to prevent the third party from doing so.
(3)Subsection (2) does not apply unless A knows that B has been harassed in the course of B's employment on at least two other occasions by a third party; and it does not matter whether the third party is the same or a different person on each occasion.
(4)A third party is a person other than—
(a)A, or
(b)an employee of A's.