The Paris-based advertising network will pay Digitas shareholders $13.50 a share in cash. The deal is believed to be the largest since WPP bought Grey for $1.5bn (拢0.75bn) in March 2005.
David Kenny, chairman and chief executive of Digitas, said: "We believe this transaction provides substantial value to our shareholders as well as strategic advantages for the combined companies. By joining Publicis Groupe, we are bringing together key assets and strengths in order to capture a larger sector, which is expanding dramatically."
This transaction is in line with the strategy announced by Publicis earlier in the year to enhance its position in the fastest-growing part of the marketing sector, the digital and mobile marketing services. Earlier this month, Publicis had been tipped to make a bid for Interpublic or Aegis, with Digitas also considered in the running for a possible merger.
The acquisition of Digitas means that digital and interactive operations will now represent 15% of Publicis' total revenue, and marketing services will now account for 34% of Publicis revenue, compared with the 28% it currently has.
The group owns ad agencies Saatchi & Saatchi, Leo Burnett and Publicis and is the fourth-largest communications group worldwide. It is also the second-largest media buying group, owning Starcom and ZenithOptimedia.
Maurice Levy, chairman and chief executive of Publicis, said: "We have been seeking to make an important strategic acquisition which could really boost our presence in the digital marketplace. The acquisition of Digitas allows us to immediately attain our goal of being one step closer to the future."
Digitas clients include American Express, AstraZeneca, Delta Airlines and IBM. It employs 2,050 staff.
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