Shares in the UK pub and restaurant group co-owned by Irish financiers JP McManus and John Magnier surged by almost 11% as it shrugged off Brexit-related pressures with a 9% jump in first half profits.
Mitchells & Butlers owns a number of UK brands including the Irish-themed O'Neill's pub chain and the Harvester network of family restaurants.
Mr Magnier and Mr McManus are long-standing shareholders and, according to the group's latest annual report, own just over 23.5% of the business through their Elpida investment vehicle.
British businessman and Tottenham Hotspur co-owner Joe Lewis is the group's largest shareholder, his Piedmont investment vehicle owning just over 27%.
Mitchells & Butlers said first half pre-tax profits grew by 8.7%, year-on-year to £75m (€85m).
Like-for-like sales grew 4%.
Like other British pub operators, Mitchells & Butlers has had to cope with higher costs, most notably from wage inflation and property costs, following Britain’s vote to leave the EU, which has also caused UK consumers to rein in spending.
“The market backdrop remains uncertain due to the political and economic landscape in the UK. However we are pleased with the progress of our trading performance and with the momentum the business carries into the second half of the year,” the company said.
It said that despite cost pressures it managed to boost adjusted operating profit by £10m to £151m during the period.
"Success in this highly competitive market is dependent on a continuous stream of improvements, and that is what we are delivering with many small advances at site level driving significant benefits in aggregate. We will maintain our focus on these initiatives, which we believe are transforming the business," said chief executive Phil Urban.