◈ About
An external checkpoint
for retained data.
Quantum Notary exists because an audit trail controlled by one system can be hard to assess independently. It places a SHA-256 digest in a Base transaction, creating an external checkpoint that can be compared with retained source data later.
Why now.
Compliance teams keep being asked to prove that something existed in its current form on a specific date. Most of the time, the only answer is "trust our records." That answer keeps getting weaker. AI-generated content, sophisticated insiders, and opaque vendor stacks all push the bar for what counts as evidence higher. A Base transaction can add an independently observable checkpoint, but it does not establish the truth, completeness, authorship, or ownership of the submitted material.
Who runs it.
Quantum Notary is a product operated by Endurance Applications. That is the name on your card statement when you buy credits, and it is the party you are dealing with. Reach it at support@quantumnotary.app.
The more useful question is what happens if this operator stops answering. Direct Base verification does not rely on our database or our API: the published verifier recomputes the digest and reads the transaction from Base itself. It still requires the retained source input, the correct digest-processing rule, and access to Base data — so the answer is a procedure you can run, not a promise we make.
2025
Work started in November. Data model, migrations, and the anchoring pipeline.
2026
First live notarizations anchored on Base mainnet. In May, Base became the only chain accepting new writes.
◇ The limits, stated plainly
What a record does not show.
A matching digest and chain record support tamper-evident chronology evidence. They do not by themselves establish who created, owned, signed, approved or supplied the data; whether its contents are true; what happened before or after anchoring; a complete chain of custody; or admissibility in any particular jurisdiction.
Not when the photograph was taken
The record dates the submission of a file, never the moment the shutter fired. Capture time comes from the camera and its metadata, both editable, neither of which we see.
Not authorship, and not ownership
Who made the file and who owns it are separate questions, answered by your raw files, your delivery records and your contracts. A fingerprint carries no information about who.
Not a notarial act, and not a legal outcome
No identity is checked and nobody witnesses anything. There is no legal presumption for this in any country, and whether a court accepts it depends on the court, its rules, and a witness who can speak to how the record was made.
Not encryption, and not anonymization
Your file stays on your computer. We receive its fingerprint and, if you send them, its name, size and type. A public fingerprint is not encryption or automatic anonymization: predictable or low-entropy data can be tested against one.
Checking it later has dependencies
Direct verification does not rely on our database or our API, but it still needs the exact bytes you kept, the processing rule, the receipt, and access to Base data through an RPC provider or an explorer.
A shared transaction discloses timing
A transaction carrying several digests reveals that those records were submitted around the same time. Nothing else about them is on chain — not the filename, not the topic, not who submitted them.
A record is marked finalized once this service observes a successful Base L2 transaction receipt. That is a service observation, not a confirmation count, and it does not monitor Ethereum L1 settlement.