Major brands, agencies and tech companies have canceled their in-person attendance in the past 48 hours due to fear over the Omicron variant.
Cannes Lions owner bought media consulting firm in 2017.
"We are deeply committed to balancing the well-being of both our people and our clients during this challenging time."
Revenue at Ascential's marketing division fell 8% in 2018, while Ebitda dropped by almost a fifth.
The two-day invite-only event will showcase the most innovative work in experiential form across the Palais.
Michael Kassan says news office will be up "as soon as possible".
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