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Privacy policy

Sunlit Workshop verifies objects, not people. The register is built so a stranger can prove a work is real without telling us who they are. This page is the whole picture — every field we store, every company that touches it, and how to make us delete it.

Last updated
August 18, 2026
Applies to
Sunlit Verify · Sunlit Tag Studio · provenance.sunlitworkshop.com
Data controller
ZDN Enterprises, LLC (d/b/a Sunlit Workshop)
Contact
zach@sunlitbytes.com

The short version

  • You can verify a work without an account. Tapping a chip or scanning a QR mark never asks who you are.
  • No tracking, no advertising, no analytics SDKs. There is no advertising identifier, no third-party analytics library, and no cross-app or cross-site tracking in any of our apps. We do not sell or share personal information.
  • We never store your IP address. Each check stores a keyed HMAC-SHA256 fingerprint of the IP instead, used only for rate limiting and duplicate detection.
  • Camera and NFC never leave the device as media. The camera decodes a QR mark on-device; NFC reads the chip's cryptographic response. No photo, video, or audio is captured, saved, or uploaded.
  • Signing in is for collectors, and it is only ever an email address. There is no sign-up, no password, no profile, and no name — a sign-in exists only for an address the workshop already registered a work to. You can delete it yourself in the app or on the web, in two taps.
  1. 1. What this covers
  2. 2. Sunlit Verify (iOS & Android)
  3. 3. Sunlit Tag Studio (iOS & macOS)
  4. 4. The web register
  5. 5. Device permissions
  6. 6. What we never collect
  7. 7. Why we hold each thing
  8. 8. What is public and permanent
  9. 9. Who else touches the data
  10. 10. Retention
  11. 11. Your rights, and deletion
  12. 12. Children
  13. 13. Security
  14. 14. International transfers
  15. 15. Changes

1. What this covers

ZDN Enterprises, LLC, doing business as Sunlit Workshop (“Sunlit Workshop”, “we”), operates the authenticity register for its own physical work. This policy covers three products:

  • Sunlit Verify (com.sunlitworkshop.verify) — the free iOS and Android app a collector uses to check a work.
  • Sunlit Tag Studio — the iOS and macOS bench tool used by workshop operators to program and audit authenticity marks. It requires workshop credentials and is not usable by the public.
  • The web register at provenance.sunlitworkshop.com, including public verification pages, the collector account area, and the workshop admin desk.

It does not cover the Sunlit Workshop storefront, third-party marketplaces we sell through, or any site we merely link to.

2. Sunlit Verify (iOS & Android)

Using the app without an account

This is the default and the whole point. When you tap a chip, scan a QR mark, or type a serial, the app sends only what is needed to check the mark, and our server records one row describing the check:

Fields stored per verification check (scan_events)
FieldWhat it is
item_id, tag_id, read_counterWhich work and chip were checked, and the chip's own tap counter.
method, verified, failure_codeHow it was checked (crypto chip, basic chip, QR, certificate tag, hologram, serial lookup, timestamp proof, or PDF signature) and whether it passed.
ip_hashA keyed HMAC-SHA256 fingerprint of your IP address. The IP itself is never written to the database or to logs.
user_agentThe browser or app version string sent with the request. Used for debugging and abuse triage.
country, regionCoarse country and subdivision code (for example US, CA) supplied by our CDN edge. This is country-level, not GPS, and not a street address.
correlation_ref, created_atA support reference we show you when a check fails, and the timestamp of the check.

Under privacy law this record is pseudonymous: on its own it does not name you, and we have no key that turns an ip_hash back into an IP address. We keep it because a provenance register that cannot notice a chip being read from four countries in one hour is not a provenance register.

If you upload a certificate PDF to check its signature, the file is read in memory to verify the PAdES signature and then discarded. We do not store the PDF.

If you sign in

Signing in is for collectors, it is optional, and it only unlocks the “My works” list and your authenticity letters. There is no sign-up. A sign-in exists only for an address the workshop has already registered a work to — enter any other address and no account is created and no link is sent. We collect and store:

  • Your email address, used to send a one-time sign-in link and to match you to works registered to that address. There is no password.
  • An authentication session (access and refresh tokens), held in the iOS Keychain or Android Keystore via the operating system's secure storage. Signing out deletes it.
  • A record of the sign-in attempt — the keyed IP fingerprint described below, the time, and whether the address matched a registered work. This throttles guessing. An address that matches nothing is not stored: the row says only that an unrecognised address was tried.

Sign-in email is handled by our authentication provider, which also records standard sign-in metadata (timestamps and the IP of the sign-in attempt) for account security.

Stored on your device only

The app keeps your most recent verification result and a short-lived verification token in the platform secure store so the result survives an app switch. Neither is transmitted anywhere beyond the checks described above, and both are removed when you sign out or delete the app.

3. Sunlit Tag Studio (iOS & macOS)

Tag Studio is an internal bench tool for workshop staff. It has no consumer sign-up. It stores, on the operator's device:

  • A device API token in the system Keychain, obtained by signing in with workshop admin credentials.
  • Operator preferences in local app settings — server URL, label dimensions, and chip-handling toggles. No personal data.

In use, it reads and writes Sunlit authenticity chips over NFC and calls the workshop API, where it can see and edit the work records that operators maintain — including a commission client's name, email, and mailing address where the workshop has entered one for shipping and for sending the authenticity kit. That customer data is workshop business record-keeping, entered by us rather than collected from the app's user, and it is never published on a verification page.

4. The web register

Public verification pages

Anyone can open a work's page. Doing so records the same check row described in section 2. One functional cookie is involved:

Cookies
NamePurposeLifetime
sunlit_verifyProves to the page that you just completed a live chip or QR check, so it can show the strongest tier of proof. HttpOnly, Secure, SameSite=Lax, scoped to /verify.5 minutes
Session cookiesKeep you signed in to the collector account area or the workshop admin desk. Set only after you sign in.Session

These are strictly necessary cookies. We set no advertising, analytics, or cross-site tracking cookies, which is why you see no cookie banner.

Reporting a suspect work

If you use the report form, we store the serial, the category you chose, the message you write, the contact detail you give us (usually an email address), and a keyed IP fingerprint for rate limiting. We read these by hand and reply to you.

Workshop records

To register a work and mail its certificate, the workshop keeps ordinary commerce records: the buyer's name, email, mailing address, and order reference, plus the photos and description of the object. These are business records under our own control, retained as long as needed to support the work and to meet tax and accounting duties.

5. Device permissions, and exactly what they do

Permissions requested by Sunlit Verify and Sunlit Tag Studio
PermissionWhyWhat leaves the device
CameraDecode the signed QR mark on a work or its certificate. The frames are processed on-device by the system barcode scanner.Only the decoded token and signature from the QR mark. No image, video, or audio is recorded, stored, or uploaded.
NFCRead the authenticity chip. Tag Studio additionally writes to chips during programming.The chip's identifier, tap counter, and cryptographic message code — the values that let the server prove the chip is genuine.

Both apps decline the permission gracefully: Sunlit Verify still works for serial lookup if you refuse the camera, and you can revoke either permission at any time in system settings.

6. What we never collect

  • No advertising identifier (IDFA / GAID), and no App Tracking Transparency prompt because we have nothing to track you with.
  • No third-party analytics, attribution, crash-reporting, or advertising SDK in either app.
  • No precise or background location. No GPS. Country and region come from the network edge, not the device.
  • No contacts, calendar, health, financial account, or biometric data.
  • No photo library access, and no microphone.
  • No sale of personal information, and no sharing for cross-context behavioral advertising, under any definition in US state privacy law.
  • No profiling or automated decision-making that has legal effect on you.

7. Why we hold each thing

Purpose and legal basis
DataPurposeGDPR / UK basis
Check record, keyed IP fingerprint, user agent, countryDeliver the verification result; rate-limit and lock out brute-force guessing; detect a cloned or shared mark; keep an audit trail for the register.Legitimate interests — running a counterfeit-resistant register and protecting it from abuse.
Email address and sessionSign you in and show the works registered to you.Performance of a contract, at your request.
Report form contentsInvestigate a suspect work and reply to you.Legitimate interests; consent for the contact detail you volunteer.
Buyer name, address, order referenceRegister the work, ship it, and send its authenticity kit.Performance of a contract; legal obligation for tax records.

8. What is public and permanent

A provenance record is meant to outlive us, so parts of it are deliberately permanent and world-readable: the serial, title, description, edition, creation date, photographs of the object, its certificate of authenticity, its X.509 item certificate, and its cryptographic timestamps — including a hash anchored into the Bitcoin blockchain through OpenTimestamps, which cannot be withdrawn once published.

Owners are never published. A public verification page describes the object only. It does not show the collector's name, email, address, or purchase price, and it does not show the country or IP fingerprint of anyone who checked the work. The check history on a page shows only the method and the timestamp.

Because the anchored data is a hash of the record about the object, no personal data of yours is written to any blockchain.

9. Who else touches the data

We use a small set of processors, each contractually bound to handle data only on our instructions and to protect it at least as well as we do. We sell data to no one.

Service providers
ProviderRoleData involved
Fly.ioApplication hosting and the register database (primary region: San Jose, US).Everything described above.
CloudflareDNS, CDN edge, and object storage for certificates, photos, and proofs.Request metadata; stored artifacts. Supplies the country and region codes.
Supabase (self-hosted by us)Authentication for collector accounts.Email address, sign-in metadata, session tokens.
ResendTransactional email delivery.Recipient email address and message contents — sign-in links, authenticity kits, and chip announcements.
Timestamp and certificate authoritiesRFC 3161 timestamping, OpenTimestamps anchoring, and issuing per-item X.509 certificates.Cryptographic hashes and object metadata only. No personal data.
Apple, GoogleApp distribution.Whatever the store collects when you download or update the app, under the store's own policy. We receive only aggregate, non-identifying install counts.

We will also disclose data if compelled by valid legal process, and to establish or defend a claim of forgery — the situation this register exists for. If the business is ever sold, the register transfers with it under this policy.

10. Retention

How long we keep things
DataKept for
Verification check records (including keyed IP fingerprint)The life of the work's record. They are the tamper-evidence history — a gap in them is a gap in the proof — and they never contain an IP address or a name.
Public provenance record, certificates, timestampsIndefinitely, by design. See section 8.
Account email and sessionUntil you ask us to delete the account, or you sign out (session only).
Reports of suspect worksUntil resolved, then up to 3 years as a counterfeiting record.
Buyer and order recordsAs long as required for support, tax, and accounting — generally 7 years.
The 5-minute verification cookie and on-device last resultMinutes; cleared on sign-out or app deletion.

11. Your rights, and how to delete your data

Wherever you live, you may ask us to show you what we hold, correct it, delete it, hand it over in a portable form, or stop a particular use. If you are in the EEA, UK, or Switzerland you have those rights under the GDPR, including the right to object to processing based on legitimate interests and to complain to your supervisory authority. If you are in California, Colorado, or another US state with a privacy statute, you have the equivalent rights to know, delete, correct, and opt out — and we do not sell or share your personal information, so there is nothing to opt out of. We will not treat you differently for exercising any of this.

Deleting your sign-in and your data

You can do it yourself, immediately, in either place:

  • In Sunlit Verify — Account → Delete account.
  • On the web — your account page → Delete this account.

Either one removes your email address, your sign-in, and every session it owns on the spot. Or email zach@sunlitbytes.com from the address you signed in with and we will do it by hand within 30 days. Verifying works never requires signing in, so this costs you nothing but the “My works” list.

Two honest limits. First, we cannot delete a work's public provenance record or its blockchain-anchored timestamp — that record is about the object, contains no personal data about you, and destroying it would break the authenticity guarantee the work was sold with. Second, we keep the pseudonymous check history, which contains no name, email, or IP address; if you believe a specific record can be linked to you, write to us and we will look at it individually.

We answer requests within 30 days and may need to confirm you control the email address before acting on one. You are welcome to use an authorized agent.

12. Children

These apps are not directed to children. We do not knowingly collect personal information from anyone under 13 (or under 16 in the EEA and UK), and Sunlit Verify asks for nothing at all unless you choose to sign in. If you believe a child has given us an email address, write to us and we will delete it.

13. Security

  • Everything travels over TLS. The apps talk only to our own origin.
  • Tokens live in the iOS Keychain or Android Keystore, never in plain application storage.
  • IP addresses are reduced to a keyed HMAC before storage; the key is a server secret we never expose.
  • Signing keys and per-item private keys are held encrypted, and item private keys are sealed to a separate encryption certificate.
  • Admin and workshop tooling requires separate credentials with scoped permissions.

No system is perfect. If you find a vulnerability, please write to zach@sunlitbytes.com before disclosing it, and we will work with you.

14. International transfers

We are a United States business and our servers are in the United States. If you use the apps from outside the US, the data described here is processed in the US. Where the GDPR applies, transfers rely on the European Commission's Standard Contractual Clauses with our processors, and the volume of personal data involved is deliberately tiny.

15. Changes

When the apps change what they collect, this page changes with them, and the date at the top moves. Material changes are announced in the app release notes. Continuing to use the apps after a change means you accept the updated policy.

ZDN Enterprises, LLC (d/b/a Sunlit Workshop), Colorado, USA · zach@sunlitbytes.com

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© 2026 Sunlit Workshop · Made in small batches, after dark — and look-uppable forever. Write to the workshopPrivacy · Support · Receipt of Provenance · Marks & tags · zach@sunlitbytes.com