5. Global timestamped receipts¶
5.1. Why hashes are not enough by themselves¶
A cryptographic hash of a document proves that two copies are bit-for-bit the same, or that they are not. It does not prove when the document first existed. Anyone can hash a file tomorrow and claim they hashed it last year. Anyone can hash a rewritten file and present the new hash as if it were the old one.
Compliance programs that care about books and records, legal holds, intellectual-property precedence, or “produce the original prompt that the model saw” therefore need a second primitive: a receipt, issued at the time of first registration, bound to the hash, that a later examiner can check without trusting the file’s custodian.
5.2. What a Verae receipt is¶
A Verae global timestamped receipt is proof of:
the hash of a block of digital information;
the time at which that hash was first registered;
the sequence of that registration relative to other registrations.
The block of digital information may be a message, an image, a document, a log segment, an AI prompt, an AI completion, or any other object that can be stored in digital media. The receipt is about the bits, not about the medium they happened to sit on when they were hashed. That is the Haber–Stornetta distinction from 1991, applied here as a product: time-stamp the data, not the disk.
5.3. What is registered, and what is not¶
Verae’s public description of sealing is that only a fingerprint leaves the customer’s systems. The object itself can remain in the customer’s DataCube. The central service therefore does not need — and in the intended design does not get — the plaintext in order to issue a receipt.
That split is the difference between a notary who reads the document and a notary who stamps a sealed envelope whose contents they never saw. The second notary can still later confirm that this envelope, with this unbroken seal, was presented at this time. They cannot tell you what was inside. For HIPAA, GDPR, and ordinary commercial secrecy, that is the desired shape.
5.4. First registration wins¶
A hash registry that allowed a later write to overwrite the timestamp of an earlier write would be a forgery machine. The rule is: the first SHA-256 (and companion hash) and its receipt win. A second presentation of the same hash returns the original receipt. A different hash is a different object — which is exactly how a revision should be modeled. Revisions get their own receipts. They do not steal the original’s time.
5.5. Sequence¶
Time on a wall clock is a social convention and a NTP configuration. Sequence inside a registration service is a data-structure fact: this hash was committed after that hash, in this chain, in this Merkle tree, in this cross-chain bundle. Verae receipts carry sequence so that an examiner can see order even when two wall-clock stamps are close enough to argue about.
5.6. Bundles¶
A receipt does not have to travel as a bare timestamp. It can travel inside a digital bundle that also holds:
private metadata the organization needs (matter id, hold flag, classification);
attached files that should be produced together;
an internal chain that cross-verifies the organizational server against Verae’s central server.
The bundle is the unit an examiner is handed: “here is the object (or a capability to it), here is the receipt, here is the metadata we claim goes with it, here is the verification path.”
5.7. What a receipt does not prove¶
A receipt does not prove that the person who registered the hash was authorized to do so. That is an access-control and identity problem.
A receipt does not prove that the object is true, only that those bits existed at that time. A false document can be timestamped as honestly as a true one.
A receipt does not prove that the organization retained the object. Proof of existence is not proof of retention. Retention is the write-once archive (Chapter 9) plus the organization’s retention schedule.
A receipt is not a HIPAA, SOC 2, or ISO certificate. It is evidence that a technical control ran.