Scope3

Market leader and de facto standard for carbon emissions measurement in digital advertising

Scope3 is an adtech sustainability company founded by Brian O'Kelley (co-founder of AppNexus) that provides the advertising industry with tools to measure, analyze, and reduce carbon emissions generated by digital advertising. The company has built a comprehensive emissions measurement platform that quantifies the environmental impact of programmatic advertising across the entire supply chain — from data centers and ad servers to end-user devices. Scope3's data and methodology have become a de facto standard for carbon measurement in advertising, with the company publishing open-source emissions data and working with industry bodies to establish consistent measurement frameworks. Scope3's core product suite enables advertisers, agencies, publishers, and ad tech platforms to understand their carbon footprint at a granular level — by campaign, publisher, SSP, or DSP — and to take action by shifting spend toward lower-emission inventory. The company also offers 'Green Media Products' (GMP), which are curated inventory segments that meet specific emissions thresholds, allowing buyers to actively reduce their environmental impact without sacrificing scale or performance. This positions Scope3 at the intersection of sustainability and media quality. Scope3 has gained significant traction in the market, partnering with major holding companies, independent agencies, DSPs, SSPs, and publishers. Its collaborative model — where supply chain participants share data to build a more accurate emissions picture — differentiates it from single-vendor approaches. The company has raised substantial venture funding and is widely regarded as the leading independent carbon measurement and reduction platform in the global advertising ecosystem.