Reforming Sustainability-Linked Bonds by Strengthening Investor Trust

Abstract

This paper explores the emergence of sustainability-linked bonds (SLBs) as an innovative instrument to finance sustainability objectives. SLBs are any type of bond instrument for which the financial characteristics vary depending on whether the issuer achieves predefined sustainability objectives. SLBs were launched in 2019, represent 7% of labeled bonds, and now exceed USD 250 billion. In the context of the growth of sustainable finance and concerns of greenwashing, this paper asks whether SLBs are an effective mechanism to attract sustainable finance. Drawing on a complete revision of the literature and interviews with practitioners, the findings highlight the potential of SLBs to contribute to sustainability financing, especially in hard-to-abate sectors. Recommendations include defining standardized KPIs based on a materiality assessment, requesting SPTs to be supported by science, and tailored step-up mechanisms. The academic literature and experts converge in their description of greenwashing risks posed by SLBs, their signaling effect, and the lack of sophistication in SLB pricing, in particular the optionality represented by step-ups. The literature differs from the practitioners’ perception on the existence of an issuance premium. Enhancing the design of SLBs represents an opportunity to add rigor to sustainable finance and better price externalities, where material topics have an explicit impact on the cost of funding.