"Shire, Britain's third-largest pharmaceuticals group, was the stand-out performer, jumping 47 to 990p on speculation that Pfizer, the US group that developed Viagra, was eyeing a bid. Rumours suggested that Pfizer had appointed bankers to examine a possible takeover of Shire. One story doing the rounds was that a bid might come at around £13 a share."
http://www.telegraph.co.uk/money/main.jhtml?xml=/money/2008/03/15/cxmktrep115.xml