Ben will join WPP's Ogilvy & Mather Worldwide network, but will continue to operate as an independent unit.
Founded in 1989, Ben is based in Stamford, Connecticut and also has offices in Atlanta. The company employs more than 100 people and had revenues of $13m (拢8.3m) in 2001 and net assets of $4.1m.
Following the acquisition, Ben will continue to be run by its existing management team led by founder Chuck Nardizzi and executives Chris Milhous and Bruce Perlman.
The acquisition of Ben continues Ogilvy's strategy of providing its clients with 360-degree branding solutions across disciplines and WPP's aim of strengthening its existing networks in important growth sectors and markets.
It is the second acquisition WPP has made this week. Earlier, it bought one of France's leading market research agencies Market Focus Research, whose clients include Unilever, L'Oreal and Johnson & Johnson.
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