Fund portfolio networks: A climate risk perspective

Within Europe, investment funds are more exposed to climate-sensitive economic sectors than banks, insurers, and pension funds. However, few climate-related financial risk assessments of the fund sector have been con-ducted. We use 8 trillion EUR of fund portfolio holdings to help fill this gap, using the network of portfolio overlaps. Funds with more polluting portfolios (brown funds) invest across more firms than funds with cleaner portfolios (green funds). This apparent diversification hides a concentration risk: brown funds are more closely connected with each other (have more similar portfolios) than green funds, which tend to herd less (have less similar portfolios with each other). This suggests that, in the event of a widespread climate-related financial shock, brown funds will face greater stress levels than green funds. A climate risk scenario exercise confirms this: among total system losses of 443 billion EUR, brown funds' losses are typically between two and three times higher than green funds' losses. Brown funds also have more systemic impact: because they play a more central role in the investment fund network, brown funds contribute twice as much towards system-wide losses as green funds. These findings suggest that, despite the growing attention paid to sustainable investing, systemic vul-nerabilities remain and many funds' portfolio diversification approaches do not yet adequately incorporate climate risk.