What must it be like to own a business that could do well under any economic condition? It could be a bit like running an ice cream stand that also sells umbrellas. It does not matter whether it is sunny or pouring with rain – the tills should keep ringing, regardless of weather conditions. Owning shares in a conglomerate is a bit like being a shareholder of that canny ice-cream vendor. Conglomerates are made up of unrelated businesses in which they have stakes – and often quite significant stakes. The key is that these separate subsidiaries should operate independently. That said, the parent company, often because of its considerable ownership in them, will probably want to have some input into how they are run. Breaking up is hard to do There was a time when conglomerates were very popular. That was until consultants managed to convince some of them (and the market) that they could better serve their shareholders by spinning off...