Guardtime is a deep-tech company founded in Estonia in 2007, specializing in data security and data management through hash-based cryptography and blockchain technologies. The company's core research and development focus is on transforming foundational cryptographic research into practical, deployable solutions for complex security challenges. Guardtime's technology is centered on Keyless Signature Infrastructure (KSI), a blockchain-based technology that provides cryptographic proof of data integrity and authenticity without relying on traditional key management. This approach enables organizations to verify the integrity of data over time, independent of trusted third parties or secret keys. The company serves clients across a range of demanding verticals, including governance, finance, energy, defence, space, and healthcare. Its solutions have been deployed across Europe, the Middle East, Asia, and North America, reflecting a global client base with high-assurance security requirements. Guardtime collaborates closely with academic institutions, industry partners, and government agencies to advance its cryptographic research and adapt its technology to evolving security challenges. This collaborative model informs both the development of new solutions and the ongoing refinement of existing technologies. Headquartered in Lausanne, Switzerland, with engineering offices in Tallinn and Tartu, Estonia, the company operates at the intersection of applied cryptography, data integrity, and distributed ledger technology.