Christophe Lambert, Publicis Conseil chairman, is being joined by Frederic Raillard and Farid Mokart, co-partners at Marcel, the boutique agency owned by Publicis.
Their new shop will go by the name Fred/Farid/Lambert. It will be based in Paris and will open in January.
The French press is speculating that the decision by Lambert to quit Publicis has been prompted in part by the appointment of Olivier Fleurot as executive chairman last week, and the departure of chief operating officer Rick Bendel, who has taken up the role of marketing director at Asda.
This has lead to speculation that Fleurot has been marked out as the heir apparent to Maurice Levy, chief executive of Publicis.
Reports say that Publicis is shocked by the news. It backed the creation of Marcel in May 2005 and since then the agency has won work including the French Coke Classic account, previously held by Havas-owned BETC Euro RSCG. It also won a share of the £200m France Telecom account, which was split between Publicis and Havas agencies.
In a statement, Raillard and Mokart said that they were three years ahead of their business plan in their progress with Marcel, which has billings of €18m (£12.2m) after only 18 months in operation.
Bollore will own a 30% stake in the start-up, with the remainder being owned by the founders.
Bollore is not going out of his way to make himself the most popular man in advertising. As well as stirring things up in the French advertising industry and muscling his way into the role of chairman at Havas at the expense of Alain de Pouzilhac, he is also pushing for two seats on the board of Aegis.
Aegis has been forced to call an extraordinary general meeting so that shareholders can vote for the second time on the issue.
Bollore argues that as the biggest shareholder, with a stake of just over 29%, he should have boardroom representation. But Aegis says that it goes against good corporate governance because there would be undue influence from one shareholder. Aegis also says that Bollore's role as the chairman of Havas is a conflict of interest.
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