The move follows confirmation yesterday from Havas that French corporate raider Bollore now holds 20% of the shares and voting rights in the company, after its rights release in October.
Havas said that a shareholder identification study taken on October 25 confirmed that Bollore holds the stock through various companies. Before the €404m (£282.7m) capital increase, which diluted Bollore's stake, he owned 22% of Havas' shares.
Now Havas chief executive and chairman De Pouzilhac wants to create a bloc of shareholders who back senior management.
The move has been sparked following a visit to the US last week to help retain Havas' £168m global ad and media accounts, put up for pitch by computer chip firm Intel.
Intel began the review of the account, which is currently held by Havas networks Euro RSCG Worldwide and Media Planning Group, last month. Insiders have speculated that the business could go to one of two WPP Group agencies -- J Walter Thompson or Berlin Cameron/Red Cell New York.
The loss of such a major global account would be a blow to Havas and it is this that is said to have convinced De Pouzilhac to put an end to the damaging speculation about the future of the advertising firm.
According to a report in The Wall Street Journal, De Pouzilhac has already won support for his plan and has the backing of institutional investors in the US, as well as two wealthy Spanish investors, the Rodes and March families.
De Pouzilhac will look for the bloc to build up a stake at least equal to that of Bollore, with whom relations are not good.
The bad blood is due in part to Bollore failing to make clear his intentions for Havas, despite calls from De Pouzilhac to do so.
Earlier this month, De Pouzilhac said: "When you have your principal shareholder and you do not know whether he is a corporate raider trying to strip the group and sell it off, or an industrialist trying to building a media holding around Havas, it creates uncertainty."
What Bollore has done is asked for board representation with reports saying he has asked for two seats on the board.
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