The move is a blow for Aegis’ Posterscope, which has worked on the business for OMG shops, including PHD, OMD UK, Manning Gottlieb OMD and M2M, for around 20 years.
Posterscope executives are believed to have been told the move was motivated by the impending £3.2 billion take-over of Aegis by Dentsu.
It is thought that Glen Wilson, Posterscope’s UK managing director, was informed the agency was losing the OMG business last week and that he and Annie Rickard, the global chief executive, told staff on Monday.
Colin Gottlieb, the chief executive of OMG EMEA, said the opportunity to drive exciting change with Talon "proved irresistible".
A 30-strong team at Posterscope currently services the OMG business and it is understood that they will be covered by Tupe legislation.
One industry source said Posterscope executives were "shocked at the brutality" and speed of the decision.
The account will move on 1 April and leave Posterscope with around 30 per cent of the £970 million outdoor market. Talon will expand to account for around 15 per cent alongside Rapport. Kinetic will continue to have 40 per cent.