Last Updated Dec 4, 2008 6:00 AM EST
WPP is not alone. Shire Pharmaceuticals made the same move, as did United Business Media.
The move makes Sorrell seem somewhat ungrateful given that he was just given the freedom of the city of London.
It may also be a pyrrhic tax victory for Sorrell, as the UK government just announced that it intends to change the law so that British companies no longer need to move to Ireland to get the benefit.