Definition
Timestamp
A trustworthy record of the exact date and time a document was signed.
In Depth
A trusted timestamp comes from an independent authority rather than your own computer clock, which is what makes it reliable. Because it is signed by that authority, nobody can quietly backdate a document or fudge when the signing actually happened. It is a key piece of evidence when the timing of an agreement matters.
The technical concept is the same everywhere. The EU and UK go further by defining a regulated "qualified electronic timestamp" under eIDAS, which carries a legal presumption that its date and time are accurate. The US has no equivalent statutory category.
Sources
- NIST Computer Security Resource Center Glossary (trusted timestamp) - A digitally signed assertion by a trusted authority that a specific digital object existed at a particular time. Official Guidance csrc.nist.gov/glossary/term/trusted_timestamp