Climate Action Data Trust (CAD Trust) is a decentralized metadata platform that links, aggregates and harmonizes carbon registry data to address data fragmentation in carbon markets and enhance transparent accounting in line with Article 6 of the Paris Agreement. The CAD Trust open-source metadata system uses blockchain technology to create a decentralized record of carbon market activity to maximize the transparency of carbon credits, minimize the risk of double counting, and enhance the overall integrity and confidence in carbon markets. The Singapore-based initiative was founded by the World Bank, The International Emissions Trading Association (IETA), and the Government of Singapore.