Following the inaugural sovereign blue bond issuance by the Republic of Seychelles last October, there have been two recent blue bond announcements. First, The Nature Conservancy recently announced its ambitious “Blue Bonds for Conservation,” aiming for $1.6 billion by 2025. Second, Morgan Stanley, working with the World Bank, sold $10 million of blue bonds aiming to solve plastic pollution in the ocean.

Joining green, social and sustainability bonds; green and sustainability loans; and other forms of sustainability finance, blue bonds add to an increasingly diverse array of alternative financing for sustainability investing. According to FTSE Russell, the total amount of sustainability investment assets under management now exceeds $31 trillion.

The World Bank defines a “blue bond” as a debt instrument issued by governments, development banks or others to raise capital from impact investors to finance marine- and ocean-based projects that have positive environmental, economic and climate benefits and states that the blue bond is inspired by the green bond concept, which people are more familiar with.