Guinness led to a scandal and criminal trial concerning the artificial inflation of the Guinness share price during the takeover bid engineered by the chairman, Ernest Saunders. A subsequent £5.2 million success fee paid to an American lawyer and Guinness director, Tom Ward, was the subject of the case "Guinness plc v Saunders", in which the House of Lords declared that the payment had been invalid. In the 1980s, as the IRA's bombing campaign spread to London and the rest of Britain, Guinness considered scrapping the harp as its logo. The company merged with Grand Metropolitan in 1997 to form Diageo.
Guinness of the barley is roasted to give Guinness its dark colour and characteristic taste. It is pasteurised and filtered. Despite its reputation as a "meal in a glass", Guinness only contains 198 kcal (838 kilojoules) per imperial pint (1460 kJ/l), slightly fewer than skimmed milk, orange juice, and most other non-light beers. Until the late 1950s Guinness was still racked into wooden casks. In the late 1950s and early 1960s, Guinness ceased brewing cask-conditioned beers and developed a keg brewing system with aluminium kegs replacing the wooden casks; these were nicknamed "iron lungs". Until 2016 the production of Guinness, as