Publicis, which carried out the transaction this morning (10 May) with the unanimous approval of its supervisory board, has cancelled the 7.5 million shares.
The company's shareholders approved a share buy-back programme in June last year.
Dentsu had to give Elisabeth Badinter, the other major shareholder in Publicis, the option to buy the shares before Publicis, but she declined.
Its agreement with Badinter, who is the daughter of the founder of Publicis, gives it 15% of the total voting rights in the company and this remains unchanged by today's transaction.
The transaction leaves Dentsu with 21.2 million shares in Publicis, representing 11.2% of the total.
Dentsu took a shareholding in Publicis Groupe in 2002, when Publicis bought BCom3, in which Dentsu had a 22% stake. BCom3 owned D'Arcy, Leo Burnett, Starcom MediaVest and Bartle Bogle Hegarty.
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