John Magnier and JP McManus, the Irish investors, have again increased their stake in pub and casual dining group Mitchells & Butlers. Through their Elpida Group investment vehicle, the horse-racing tycoons have pushed their holding from 8% to just over 9%. The duo, who once tried to buy Manchester United football club, now hold almost 37 million shares in the operator of All Bar One and Harvester. They are the second biggest investors in the group, after Robert Tchenguiz. The shares are currently priced at 187p, capitalising the group at £765.8m.