(1) If 2 persons have an agreement under which an employee of 1 of them works solely or mainly in connection with a business carried on by--(a) the other, or(b) both of them,then the 2 persons constitute a primary group.
(2) In this section--
"agreement" means an agreement, arrangement or undertaking, whether formal or informal, whether express or implied, and whether or not the agreement, arrangement or undertaking includes provisions in respect of the supply of goods or services.
"person" includes a set of persons.
Note : Section 175E allows the Nominal Insurer to exclude persons from a group constituted under this section in certain circumstances.