Guy Marks
Guy Marks is the Chief Client Success Officer of Omnicom Media.
Last updated Oct 18, 2026 by the ATDb Editorial Team
AI-drafted from public sources4 sources cited
Bio
Guy Marks is the Chief Client Success Officer of Omnicom Media. Omnicom Media encompasses seven agency brands, including OMD, PHD, Hearts & Science, Initiative, UM, Mediahub, and the data broker Acxiom. Marks joined Omnicom Media Group in 2014 following Omnicom's acquisition of Mobile5, a global UX, design, and technology consultancy he co-founded. He previously served as CEO of OMG EMEA before being named CEO of PHD Worldwide, succeeding Philippa Brown. Source 1: digiday.com — Omnicom's reshuffled leadership are adland's new power ... Source 2: adweek.com — PHD Worldwide Names Guy Marks CEO
Career
Global CEO
PHD · 2023–2025
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