The deal could spark a battle for the merged company's comms account between FD and Brunswick - the LMS incumbent for more than three years.
The deal, confirmed last week, will create a property giant in London's West End - where two-thirds of Derwent Valley and LMS's property is located, and where prime commercial floor space costs up to £100 per square foot.
FD managing director Stephanie Highett heads the Derwent account and Brunswick partner Simon Sporborg heads the LMS brief.
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