Fluree's main product, Fluree Core, is an open-source graph database that combines permissioned blockchain technology, semantic web standards, and data-centric security policy controls to help developers store and manage data in a decentralized and trusted format. The technology combines transactions into immutable, time-stamped "blocks" and locks each block using asymmetric cryptography, making data completely tamper-proof. Digital signatures are used for complete proof and visibility into the data lifecycle.