Glossary
What is a timestamp
A date not set by whoever signed, which is why it counts.
Timestamp
Certification, issued by an independent third party, that a specific document existed exactly as it stands at a given instant.
The value sits in "independent third party". If the date were set by whoever stores the document, you would have to trust them. Set by an authority outside both parties, the date stands on its own.
What it certifies and what it does not
| Certifies | Does not certify |
|---|---|
| That this document existed on that date | That what it says is true |
| That it has not changed since | Who wrote it |
| That the time came from a third party | That it was lawful |
Worth knowing
It is the difference between saying "I had this in March" and being able to prove it. In a dispute, the first is your word and the second admits no reply.
Watch out
The seal covers the exact file. Reprint it or convert it and the file changes, so the seal no longer matches — correctly.
›Does it expire?
The date certification does not expire. What ages are the algorithms, which is why long-retention documents get re-sealed.
›Can I check it myself?
Yes, with no account, on the public verification page.
›Can something old be sealed?
Yes, but the certified date is today's, not the original.
A real case
The situation
A studio wants to prove a design was theirs before a client meeting.
What you do
- Seals the design the day it is finished
What you get
When a similar product appears months later, the date does not rest on their word.
The situation
Two parties argue over which of two versions came first.
What you do
- Checks the timestamp on each
What you get
The order is set by a third party rather than by memory.
The situation
A company saves a file and trusts the system's modified date.
What you do
- Timestamps the document when it is finished
What you get
The date can no longer change when the file is copied.
The situation
You want to prove a report existed before a meeting.
What you do
- Timestamps the report the day it is closed
What you get
The proof does not rest on emails or diaries.
The situation
A client doubts the annex they received is the one that was sealed.
What you do
- Compares the annex's fingerprint with the registered one
What you get
The doubt is settled in seconds without argument.
The situation
A document is sealed and afterwards a typo is corrected.
What you do
- Seals the corrected version too
What you get
Both versions carry their own date and are distinguishable.
This article answers
- what is a timestamp
- what a document timestamp is for
- timestamping authority
- how to prove a document's date