Dirty Business: Transition Risk of Factor Portfolios

Between 2016 and 2023, the top 10% of carbon-emission-intensive firms (heavy emitters) accounted for over 90% of all Scope 1 emissions from U.S. public companies. We observe that about 35% of the market capitalization of ‘Value’ portfolios, compared to 5% of ‘Growth’ portfolios, regardless of how Value and Growth are defined, was comprised of heavy emitters. When we split the Big Value portfolio into heavy- and light-emitter stocks, we find that these two portfolios had similar realized (raw and risk-adjusted) returns and expected returns, as measured by Implied Cost of Capital, suggesting limited incremental compensation for transition risk. We also find that Big Growth low-emitter stocks consistently had lower expected returns than Big Value low-emitter stocks, with the spread widening in recent years, despite similar emission levels. This indicates that factors beyond climate concerns are necessary to fully explain the superior performance of Growth stocks relative to Value stocks over the past decade.