Scope3
RebrandedNew York, NY, United States · Founded 2022
51-200 employees · $34M
Sourced & current · updated Oct 12, 2026Website
Scope3 was the advertising sustainability company Brian O'Kelley and Anne Coghlan founded to measure and reduce the carbon emissions of digital advertising. It renamed itself Apostra on September 23, 2026 as it pivoted to AI agents that buy and sell media; its carbon-measurement product continues as Scope3 by Apostra.
Where they sit
Stack tier: Marketing Technology (C)
Marketing Technology
Pioneer in programmatic advertising carbon measurement; rebranded as Apostra in 2026 to lead AI agent-driven media buying