OpenX Names Robert Horler as CEO to Drive Its Next Phase of Growth

OpenX, The Intelligent SSP™, has announced the appointment of Robert Horler as its Chief Executive Officer. In his new role, Horler will lead the company through its next phase of growth, focusing on the evolution of programmatic advertising through buyer-direct relationships, AI-enabled solutions and enterprise software offerings.

Horler joins OpenX following a period of sustained business momentum, with the company recording 15 consecutive quarters of year-over-year revenue growth. He brings three decades of leadership experience across media, advertising and adtech, including operational responsibility for organisations generating more than $1 billion in revenue.

Throughout his career, Horler has worked closely with product and engineering teams to translate technical differentiation into commercial value and bring data-driven solutions to market.

OpenX Looks to Accelerate Growth Through AI and Programmatic Innovation

Commenting on the appointment, Tim Cadogan, Co-Founder and Chairman of the Board at OpenX, said Horler has a proven track record of growing businesses while maintaining a strong focus on customers and their evolving needs, including agentic optimisation. He also highlighted Horler’s experience in operational excellence, profitable growth and building strong organisational cultures.

As artificial intelligence reshapes content discovery and media buying, OpenX sees an opportunity to strengthen the technology connecting publishers and buyers. The company aims to help partners develop profitable revenue streams through platforms such as OpenXBuild™, which combines an independent identity graph, 100% cloud-native infrastructure and AI enablement.

The platform is designed to support publisher control, data ownership and more effective monetisation, while operating on a foundation of trust.

Robert Horler Brings Leadership Experience Across Media and Adtech

Before joining OpenX, Horler founded, built and sold Diffiniti, a search and performance marketing agency. He subsequently served as CEO of Dentsu Aegis Network across the US and Northern Europe, where he led sustained growth in revenue and earnings.

More recently, he served as CEO and then Board Member at Whalar, a global creator and social agency acquired by Accenture earlier this year. During his tenure, he supported the founders in scaling the business from 40 to more than 300 employees, while contributing to the development of the creator economy and the evolution of influencer marketing into a data-driven discipline.

Horler has also held senior positions on the publisher side at The Financial Times and News Corp, giving him direct experience of the challenges publishers face in monetising their content and audiences.

Leadership Transition at OpenX

Horler succeeds Joshua Metzger, who served as interim CEO and will continue in his position as OpenX’s Chief Legal Officer.

Cadogan acknowledged Metzger’s contribution during the interim leadership period, noting that his focus on organisational execution and priorities helped guide the company. Metzger will continue to support OpenX’s leadership and contribute to its future direction in his legal role.

Horler’s appointment comes as OpenX looks to build on its recent growth and expand its role in the evolving programmatic advertising ecosystem, with a focus on AI-driven capabilities, buyer-direct relationships and technology that supports publishers and advertisers.