Epsilon

Updated in January, 2026

Epsilon is a global advertising and marketing technology company within Publicis Groupe. They specialize in connecting advertisers with consumers to drive performance while upholding privacy and protecting client data. Epsilon helps clients leverage their first-party data to enhance, activate, and measure campaigns confidently, supporting an open, privacy-first advertising ecosystem. With decades of experience, Epsilon has developed the industry's most comprehensive identity graph, enabling brands, agencies, and publishers to reach real consumers across all channels and the open web.