But the report on projected portfolio growth has competitors gaining ground.
Performance mainly down to Mars and Adidas wins for MediaCom and $2 billion GSK account for Publicis.
The group had a net new business balance of $2.34 billion, well ahead of second-place finisher Publicis Media's $376 million.
Havas Media follows in the runner-up spot, with a wins-versus-losses balance of $495 million.
GLOBAL - Carat has been named the world's leading media agency network once again, after regaining the top spot from MediaCom.
RECMA’s latest Qualitative Evaluation China report puts ZenithOptimedia in top position (Dominant Profile with 22 points), Carat in second (High Profile with 19 points) and Mindshare in third (High Profile with 18 points).
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