Guardtime signatures authenticate electronic data, proving the signing time, signing entity and that not a single bit has changed since the signing time.
Makes electronic data tamper-evident
Think of Guardtime as a lie detector for electronic data. It enables you to conclusively and irrefutably prove that the signed data has not been compromised.
Signed data can be verified by anyone
Guardtime openly publishes all the tools needed to verify the signatures with no need to consult any third party, including Guardtime.
Keyless Signatures never expire
Guardtime signatures do not use any public or private cryptographic keys for the purposes of verification thereby ensuring that the integrity and authenticity properties of the data will never expire.
Keyless Signatures are a combination of hash function based server-side signatures and hash-linking based digital timestamping delivered using a distributed and hierarchical infrastructure. The digital timestamping component of the service is officially certified and Guardtime is accredited as a timestamp authority by the European Union. See here for more details.