Atkinson will lead AdMaxim’s EMEA sales team as the mobile ad network and consultancy moves to build its business outside the US.
The London-based sales force will expand to around 20 to 30 people over the next 12 months.
Atkinson resigned from Clear Channel Outdoor in November 2011. He joined as group sales director in September 2008 from The Independent and The Independent on Sunday, where he was deputy commercial director.
Prior to joining The Independent and The Independent on Sunday in June 2007, Atkinson was group sales director at Titan Outdoor (now part of JCDecaux) from July 2006.
He has also worked at Daily Mail publisher Associated Newspapers between 1989 and 2006, where he held several commercial roles including deputy sales director, Associated Newspapers, and deputy sales director, Mail on Sunday.
Atkinson said: "AdMaxim will cut through the complexity of mobile because it is the first platform to bring all the options together and is driven by a bespoke optimisation system that out-performs the competition."
Following AdMaxium's expansion into Europe, Andrew Edwards, UK group chairman and chief executive and president of Central Europe at Leo Burnett, has joined its board.
Khan said: "The future of mobile marketing is integration, but the current complexity of the mobile sector is a barrier to entry for brands. It is holding back mobile advertising spend.
"We deliberately set out to create a mobile platform that can offer brands the flexibility to use any kind of mobile format or creative approach, combined with precision data optimisation."
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