This article introduces a new measure called the Corporate Biodiversity Footprint (CBF) to quantify a firm's negative impact on biodiversity and examines whether this impact is priced in stock returns. The CBF, developed by Iceberg Data Lab (IDL), aggregates biodiversity loss caused by a firm's activities related to land use, greenhouse gas emissions, water pollution, and air pollution. The study finds that the CBF does not explain cross-sectional returns between 2019 and 2022. However, a biodiversity footprint premium emerged after the Kunming Declaration in October 2021, with stocks of firms having larger footprints losing value in the following days. Similarly, the launch of the Taskforce on Nature-related Financial Disclosures (TNFD) in June 2021 had a similar effect. These findings suggest that investors are starting to require a risk premium for firms facing future regulation or litigation related to biodiversity preservation. The study also examines the determinants of the CBF, finding that larger firms, those with higher carbon emissions, and those with lower environmental scores tend to have larger footprints. The results highlight the growing awareness and pricing of biodiversity risks in financial markets.This article introduces a new measure called the Corporate Biodiversity Footprint (CBF) to quantify a firm's negative impact on biodiversity and examines whether this impact is priced in stock returns. The CBF, developed by Iceberg Data Lab (IDL), aggregates biodiversity loss caused by a firm's activities related to land use, greenhouse gas emissions, water pollution, and air pollution. The study finds that the CBF does not explain cross-sectional returns between 2019 and 2022. However, a biodiversity footprint premium emerged after the Kunming Declaration in October 2021, with stocks of firms having larger footprints losing value in the following days. Similarly, the launch of the Taskforce on Nature-related Financial Disclosures (TNFD) in June 2021 had a similar effect. These findings suggest that investors are starting to require a risk premium for firms facing future regulation or litigation related to biodiversity preservation. The study also examines the determinants of the CBF, finding that larger firms, those with higher carbon emissions, and those with lower environmental scores tend to have larger footprints. The results highlight the growing awareness and pricing of biodiversity risks in financial markets.