Isobar will operate in 19 markets with billings of around $500m (£273m), with 45% of that coming from the online media operations of Carat Interactive, which has more than 20 offices around the world. It will be headed by Nigel Morris, who takes the role of president of Isobar.
Morris, a founder member of the Digital Marketing Group in the UK, was named Carat's first global president of interactive business last year. He will report directly to Aegis CEO Doug Flynn.
The launch will be the fifth network for Aegis, sitting alongside media networks Carat and Vizeum, the outdoor company Posterscope, and market research group Synovate. The group said that it was investing in digital because of the rise in online advertising, as well as the rapid development of search and affiliate marketing.
"The creation of Isobar provides us with a platform from which to build our digital business. The market for digital services is at a tipping point, with major brands now realising the potential benefits for their business in terms of both brand and response effectiveness," Flynn said.
In a trading statement issued at the same time, Aegis said that its March estimates of a 5.3% rise in global adspend are now looking conservative, and that revenues are comfortably ahead of last year so that it remained on track to meet expectations on its full-year results.
However, it warned that the strength of the pound would hold back growth in its results when translated from local currencies, with the US dollar down 10% compared with the same period last year.
Aegis said that European growth in the media sector is not yet at the pace of the US or Asia, and that the French and German markets remain difficult, but southern European countries are performing well.
Shares in Aegis, traded on the London Stock Exchange, rose when the market opened this morning by 2.5% to 89.43p, an increase of 2.18p.
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