Global CEO Christian Juhl confirmed the move this week.
He will become global CCO of McCann Worldgroup and McCann.
Exclusive negotiations in progress between performance agency and martech group.
Clients will be advised on which channels, and eventually media vendors, are causing the most carbon emissions in effort to slash advertising's carbon footprint.
Hagedorn has been with Omnicom since 2004 but is leaving the company.
All regions contribute to year-on-year recovery with the international business improving the most.
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