WPP, the advertising world's answer to the Borg in Star Trek, has announced it second acquisition of the week, and this time it is a French agency that is to be assimilated.WPP's wholly-owned operating network Kantar has agreed to acquire 87% of the share capital of Press Index in France at a price of €6.81 per share.Once the deal has been completed Kantar will make arrangements to buy out the minority shareholders in Press Index at the same price.Founded in 1997 and head-quartered in Boulogne Billancourt, near Paris, Press Index is a search and media intelligence agency, employing around 210 people across offices in France, UK, Spain and Italy.Press Index's consolidated audited revenues for the year ended 31st December 2011 were €17.5m, and at the end of 2011 it had gross assets of €12m.On Tuesday, WPP announced the acquisition of a 70% stake in Foster Informatica, a digital agency based in São Paulo, Brazil.JH