Factor Exposure Heterogeneity in Green and Brown Stocks

TL;DR

This paper investigates how green and brown stocks differ in their factor exposure heterogeneity, revealing that green stocks are generally more homogeneous and that this heterogeneity has increased over time.

Contribution

It introduces the peer-exposure ratio to analyze factor exposure heterogeneity in green versus brown stocks, highlighting differences and temporal changes.

Findings

Green stocks show less factor exposure heterogeneity than brown stocks.

Shift from brown to green stocks reduces differentiation in factor exposures.

Factor exposure heterogeneity in green stocks has increased over recent years.

Abstract

Using the peer-exposure ratio, we explore the factor exposure heterogeneity in green and brown stocks. By looking at peer groups of S&P 500 index firms over 2014-2020 based on their greenhouse gas emission levels, we find that, on average, green stocks exhibit less factor exposure heterogeneity than brown stocks for most of the traditional equity factors but the value factor. Hence, investment managers shifting their investments from brown stocks to green stocks have less room to differentiate themselves regarding their factor exposures. Finally, we find that factor exposure heterogeneity has increased for green stocks compared to earlier periods.