The Carbon Content of Billionaire Wealth: Composition, Concentration, and Taxation

How large are billionaires' carbon footprints? While increasing evidence highlights large disparities in emissions between and within countries, detailed individual-level data on emissions portfolios remain scarce. In this paper, we analyze the wealth composition of the top 501 billionaires and construct a dataset linking each of their assets to emissions. According to our ownership-based emission accounting framework, every USD million held by billionaires is associated with more than 65 tCO2e per year -about 10 times the annual carbon footprint of the average person. Further, our estimates reveal an extreme concentration of wealth among the super-rich and, even more so, emissions. About 50 billionaires account for nearly three-quarters of total emissions in our sample, with publicly traded equity in Basic Materials, Industrials, and Utilities playing a disproportionate role as emission sources. Emission intensity is key: 97% of the variance in log emissions is explained by intensity differences, suggesting that scale effects play a limited role and carbon footprints are almost entirely driven by investment choices. The highest-emitting billionaires -including some of the wealthiest- derive a substantial share of their emissions (between 44 and 66%) from hard-to-abate sectors. Comparing alternative taxation schemes targeting both extreme wealth and emissions, we show that the introduction of a new progressive carbon wealth tax can potentially achieve three objectives: progressively taxing billionaires to curb inequality, targeting the most polluting activities, and raising substantial resources to finance a sustainable and equitable transition.