The review, which began in September, saw OMD fight it out against Publicis Groupe-owned Starcom with which it shared the media account.
OMD currently handles McDonald's media planning and all national buying in the US, with Starcom handling youth planning and international media planning and buying, including the restaurant chain's business in the UK.
The loss of the McDonald's account for Starcom is tempered by its win of Coca Cola's $350m consolidated media account earlier this week, the loss of which came as a bitter blow to Universal McCann.
McDonald's began the review as part of an effort to boost the efficiency of its marketing spend in the face of changing consumer fashions and fierce competition from rivals like Burger King and a host of newer rivals, such as coffee shops and health-food restaurants.
The review was overseen by the company's global chief marketing officer, Larry Light, and coincided with the launch of the burger giant's first global advertising campaign, "I'm lovin' it", which features the pop star Justin Timberlake as its new global brand ambassador.
The global "I'm lovin' it" campaign was developed by Munich-based Omnicom agency Heye & Partner, part of DDB Worldwide, which is a long-time McDonald's agency.
A spokeswoman for McDonald's refused to confirm the appointment of a sole media agency, but did say the company was evaluating its marketing opportunities in 2004 and beyond.
"You can expect to hear more from us on our new marketing leadership initiatives in the future. Until then, anything else is pure speculation," she said.
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