Agreebase uses privacy-preserving defaults, but a publication choice can make content or identity permanently public. Treat every on-chain publication decision as irreversible.
Default publication
For ordinary agreements, declarations, and witnessed records, the default blockchain record contains the AGR reference, body hash, evidence metadata hash, and completion time. It does not contain the body or party details.
For notarizations, the default chain record contains the content hash, content type, hash algorithm, selected advisory metadata, evidence metadata hash, and completion time. File bytes are never sent to Agreebase through the notarization request. A default notarization record reads as plain text, for example:
Agreebase.com - AGR-2026-000456
Content hash: sha256:7c2e9a1f4b8d3c6e0a5f2b9d1c7e4a8f3b6d2c9e5a1f7b4d8c2e6a9f3b1d5c7e
Content type: file
Hash algorithm: sha256
Label: Signed lease scan
Size bytes: 812441
Metadata hash: sha256:2f8b4e1a7c9d3f6b0e5a2d8c1f4b7e3a9c6d2f8b5e1a4c7d9f3b6e2a8d1c5f7b
Completed: 2026-07-20T09:11:04Z
Nothing here identifies the file's original name, path, or contents; only the hash and whatever advisory label the creator chose to attach.
Data kept off chain by default
The following are not included in the default public blockchain record:
- Ordinary agreement or declaration text.
- Party names, email addresses, and contact-point values.
- Raw IP addresses and raw user-agent strings.
- OTP codes.
- Signature execution payloads.
- Private participant history and operational metadata.
Party-facing evidence metadata uses redacted contact values, scoped HMAC hashes, and privacy-preserving network evidence. It is a deliberately smaller package than Agreebase's internal operational state.
Opt-in publication
Creators can independently enable:
- Full text for ordinary records.
- Normalized text for text notarizations, subject to the public text limit.
- Verified party details, which can include role, entered display name, and verified signing email.
Full-text publication is appropriate only for content intended to be globally public. A hash is not magic secrecy: a short or predictable input may be guessed by someone who can test candidate inputs. Keep sensitive content off chain.
When verified party publication is enabled, affected signers and witnesses are notified and must acknowledge the disclosure before finalizing.
Public proof methods
GitHub, X, and Reddit signature methods work by having Agreebase generate a short block of proof text and asking the signer to publish it somewhere only they control; a gist, a post, a profile update. Something like this:
Agreebase.com Signature Proof
Record: AGR-2026-000123 (v1)
Method: github_gist
Session: 8f3c1a2e-...
Proof ID: 9d21b7...
Issued: 2026-07-20T14:02:11Z
Expires: 2026-07-20T14:32:11Z
Proof digest: sha256:4a1e9c...
Agreebase then fetches the published URL and confirms the page contains that exact text (Reddit checks the post title instead, since Reddit strips formatting from bodies). The proof has to be genuinely public to be checked this way, so the post itself, the account that made it, and anything else visible on that platform are naturally visible to anyone who can view it. Choosing email, Telegram, or passkey avoids that particular public-post requirement, subject to provider availability.
Once a signature method is verified and the record seals, the external post has done its job; the proof and its verification result are already recorded by Agreebase. The gist, X post, or Reddit post can be deleted at that point without affecting the sealed record. It should not be deleted before the signature method completes, since Agreebase needs to fetch it during that window.
Notarization privacy
For file notarization, Agreebase receives a client-computed hash and advisory metadata rather than file bytes. It does not receive a local path, file creation or modification dates, EXIF data, or the source file.
For text notarization, the server receives the text in order to normalize and validate the supplied hash. Text remains private unless the creator enables public text publication.
Verification privacy
Public verification can confirm or deny an artifact match and can expose public chain metadata. It does not expose private signer names, contact addresses, contact hashes, network evidence, or signature execution payloads.
Policy boundary
This page covers how Agreebase behaves: what gets published, what stays off chain, and what a given choice can't be undone. For how long data is kept, who can request access or correction, and other legal and jurisdictional questions, see Data handling.