Privacy
Last updated 20 September 2026. This page covers the hosted demo at grainmark.app (alias proofsheet.rick3.dev).
What you send
If you seal or verify media, the file bytes are uploaded to this server so it can build or check a Grainmark sidecar. There are no accounts. We do not use the files for advertising or model training.
What we keep
- A sidecar (MediaAnchor JSON) under a random id, plus a small metadata record (hash, optional source URL, created time, publish flag).
- The uploaded file itself is written to a private temp directory and deleted when that request finishes.
- A sidecar includes three JPEG probe frames of the media. Sharing or publishing a sidecar shares those images.
Private vs published
New seals stay private. The public list, lookup, metadata, download, and verify-by-id paths do not expose a private seal unless you send the create-time access token or you publish it. Publishing is an explicit action. Old test seals from before this rule may remain on disk; they are not listed.
What a green result means
A match is an unsigned visual comparison against a sidecar you supplied or a seal this host still holds. It is not a camera signature, trusted timestamp, or a claim that the scene was never generated or edited outside the tested visual envelope. Audio and playback timing are not compared.
Logs and contact
The reverse proxy and application may log request time, path, status, and client IP. No account cookies. Questions: hello@rick3.dev.