Ashton Insurance Brokers CC t/a Walmer Insurance Brokers and Another v Independent Municipal and Allied Trade Union

The respondent trade union (IMATU) operated a long-standing group short-term insurance scheme for its members. In 1989 it appointed Walmer Insurance Brokers, represented by its sole member Michelle Riddle, as its in-house broker to administer the scheme. Walmer obtained exclusive access to IMATU’s members, administered the scheme, and shared commission and profits with IMATU. In 2001, IMATU sought to introduce new contractual terms upon renewal, including disclosure of member lists and a restraint of trade. Walmer refused. IMATU terminated the relationship with effect from 1 April 2001. Thereafter, IMATU alleged that Walmer and Riddle canvassed IMATU members to leave the scheme and join a competing scheme, using confidential information obtained through the relationship. Competing High Court applications followed: Walmer sought declaratory and interdictory relief to preserve its role, while IMATU sought an interdict restraining Walmer and Riddle from soliciting its members and using scheme information. The High Court granted IMATU a final interdict. Walmer and Riddle appealed to the Supreme Court of Appeal.

The appeal was dismissed with costs. The permanent interdict granted by the High Court in favour of IMATU remained in force.

The case is an important authority in South African law on fiduciary duties arising from commercial and agency-type relationships, particularly in the insurance brokerage context. It confirms that fiduciary obligations may arise from the substance of a contractual relationship and can survive termination. The judgment clarifies that brokers or agents with exclusive access to clients and confidential information may be restrained from exploiting that position to the detriment of the principal, even in the absence of an express restraint of trade.