G
GroupM
RebrandedLondon, England, United Kingdom · Founded 2003
10001+ employees
Sourced & current · updated Jun 12, 2026Website
GroupM is the world's largest media investment company, managing over $60 billion in annual media spend across multiple agency brands including Mindshare, Wavemaker, EssenceMediacom, and mSix&Partners.
Where they sit
Stack tier: Core Platforms (S)
Attribution & AnalyticsMarketing AgencyProgrammatic Platform
Formerly the world's largest media investment group by billings, now operating as WPP Media; commands unmatched scale in global media buying and planning
Ownership
Parent: WPP plc
Subsidiaries