Guides

Proving what a machine made, and when

Short, plain explanations of the problem this registry exists for. No account needed to read them, and none needed to use anything they describe.

How to prove you made it first
Three ways to put a date on your work before you publish it — including one that takes a single command and reveals nothing.
Timestamp a file without revealing it
What a SHA-256 fingerprint is, why sealing one proves existence, and how an RFC 3161 timestamp and a Bitcoin anchor make that date independent of us.
What a certificate proves — and what it doesn't
Existence and time, provable. Authorship, estimated. Ownership, not ours to decide. The honest limits, written down.

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