Vincent Bolloré, the French investor, on Thursday ended his four-year battle for representation on the board of Aegis, the media buying and research group, saying the performance of the company was “no longer an important point of concern”.

Mr Bolloré’s eponymous conglomerate owns a 29.9 per cent stake in Aegis and since 2005 has made several attempts to place his own candidates on the board in a dispute over management.