Keep the original yourself
The browser file flow computes SHA-256 locally and does not upload original file contents. Notarization sends the digest and metadata such as filename, size and available type. Metadata stays off-chain; it can still be present in service records and downloaded proof. Quantum Notary cannot reconstruct your original from a fingerprint.
Public fingerprints have limits
Base transactions contain raw digest slots. They do not contain filenames, topics, external IDs, tenant data or service IDs. Records sharing a transaction disclose that they were submitted in the same short window.
A digest is not encryption or automatic anonymization. Predictable candidate files or values can be hashed and compared with a public digest. Consider that risk before recording sensitive or easily guessed material. See fingerprint limits and the privacy notice.
Lifetime records
A successful notarization creates a lifetime record with no scheduled expiry. Service proof records are retained for the lifetime of Quantum Notary for future reference. The service does not support deleting notarization records or proof history, including after refunds, capacity reductions or account closure. Neither we nor a customer can remove Base fingerprints. Applicable personal-data rights remain separate; the privacy notice explains those rights.
Lifetime-of-service retention does not promise uninterrupted access, continued operation or positive proof issuance during an integrity hold. Keep the exact file and export available proof packages to storage you control. Independent checking also depends on access to suitable historical chain data. Follow proof preservation.
Keep your own evidence package
Open Records to find your notarization and download available receipts and proof. Keep those exports with the exact original file in storage you control. A service record is not a backup of your file, and retaining it does not guarantee that a report will always be available to download.
For a check using Base history directly, preserve the Python verifier package, its SHA-256 checksum and the setup instructions alongside your evidence.