Sir Marcus Smith was called to the Bar in 1991 and was appointed Queens Counsel in 2010. He was appointed as a Chair at the Competition Appeal Tribunal in 2009, and has sat regularly since that date, hearing cases across the full range of work at the Tribunal. In 2017, he was appointed to the High Court (Chancery Division). He hears cases across the whole range of Business and Property Courts work, as well as sitting in the Upper Tribunal (Tax and Chancery), the Administrative Court, and the Patents Court. He is one of the judges authorised to sit as a judge of the Financial List. Between 2019 and 2021, Sir Marcus Smith was the Supervising Judge for the Business and Property Courts of the Midland and Western Circuits and Wales.