![David Mercer of LMAX Exchange](https://s.wsj.net/public/resources/images/FN-AA347_MERCER_M_20170421040114.jpg)
David Mercer moved to London from Belfast with his parents when he was just 11. At the age of 18, he joined a training programme at Ernst & Young but instead of becoming a chartered accountant he joined Swiss bank Credit Suisse.
Today, aged 46, he is chief executive of currency trader LMAX Exchange, based in Shepherd’s Bush in west London, and he is on a mission – to clean up the industry.