Former top Clinton adviser and one-time Burson-Marsteller CEO Mark Penn is set to serve as chairman and CEO of the combined network.
WPP says past mergers of creative and digital agencies mean this new combination should work but there are hurdles.
Pranksters have set up spoof domain names and social media accounts in name of GreyKQA, AKQGrey and AKQA Group.
Sources say it was always WPP's intention that Grey and AKQA brands would co-exist 'for some time'.
Purchase launches iProspect in the market.
The acquisition puts a renewed emphasis on creativity in marketing, industry experts say.
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