Guardtime

Estonian | Tallinn, Estonia

About Guardtime

Guardtime is an Estonian-born cybersecurity pioneer founded in 2007, specialising in blockchain-based data integrity and authentication. The company's core technology is Keyless Signature Infrastructure (KSI), an industrial blockchain using hash-function cryptography that is inherently quantum-resistant. Guardtime provides quantum-immune data integrity solutions for defence, e-governance, healthcare, energy, and supply chain sectors.

The Estonian government uses Guardtime's technology to secure health records for over one million citizens.

Capabilities

Verified March 2026

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