In-office policy was updated in November, when Omnicom acquired Interpublic Group.
McCann Worldgroup has worked with the brand for two decades.
Latest results reveal uneven performance across regions, with Asia-Pacific facing challenges amid shifting client priorities and global cutbacks.
Shareholder vote due to take place on 18 March.
First set of results since Havas was spun off from Vivendi.
A global study by BetterBriefs and Flood + Partners, in partnership with the IPA and WFA, reveals a broken approval process, eroding trust between marketers and agencies, and a creative industry struggling to produce standout work.
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