4Existing insurance companies
(1)A body that was, immediately before the commencement of this Act, authorised under section 3 or 4 of the [1981 c. 31.] Insurance Companies Act 1981 to carry on in the United Kingdom insurance business of a class specified in Schedule 1 or 2 to that Act (or a part of such a class) is authorised to carry on there insurance business of the class identified by the same number in Schedule 1 or 2 to this Act (or that part of such a class).
(2)A body may not carry on industrial assurance business by virtue of this section unless—
(a)it was carrying on such business immediately before 1st January 1982, or
(b)it was immediately before the commencement of this Act authorised to carry on such business under section 3 of the Insurance Companies Act 1981.