The founder of Dunelm, the homewares retailer, was on Thursday evening unveiled as a major shareholder in High Street retail giant Marks & Spencer. Bill Adderley is the company's biggest private investor with a 3% stake, market filings have revealed, with shares worth around £244m on the basis on Thursday's closing price. Adderley, whose family still own more than 50% of Dunelm, is reported to have been building his stake for the past year. The news prompted M&S shares to rise from around 489p to 505p, although they retreated slightly on Friday. NR