Global timestamped receipts
===========================

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.**

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.

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.

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.

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.

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."

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.