Private by design.
The current local edition processes documents on your computer. The vision extends that approach across devices.
GrainMark by 0–8 Capital GmbH
PRIVATE PROVENANCE. PHYSICAL DOCUMENTS.
Documents stay private.
Trust stays attached.
Local prototype available
For the documents that still get printed, signed and returned.
Join the pilot Become a founding partner
01 / WHY GRAINMARK
Paper travels.
Context gets lost.
A board pack. A signed letter. A returned investment document. Once paper leaves your hands, connecting a copy to its issuance and intended recipient becomes harder.
GrainMark explores a quieter layer of traceability: recipient-specific grain, carried by the document itself.
Identity that travels.
Recipient-specific patterns connect a marked copy to a private issuance record, even beyond the original PDF.
Confidence after print.
Check scans for expected grain. Build evidence for a review, with the limits of probabilistic detection kept in view.
02 / WHERE IT MATTERS
When the copy
matters.
Built around real document journeys.
Shaped with the teams who own them.
Board & shareholder materials
Connect distributed copies to their intended recipients.
Investment documentation
Keep issuance context attached as documents change hands.
Corporate & legal correspondence
Support the review of paper that is mailed and returned.
Certificates & confirmations
Explore traceability beyond the digital original.
03 / PROGRESS, WITHOUT THE PROMISES
Working today.
Building toward tomorrow.
A working local prototype.
A clearly defined product vision.
A local foundation.
- grains applied to PDFs
- Local checks and scans for expected grain
- Grain, synchronization results
- Marked PDF and private receipts in a ZIP
- Delivery-file hash and key management
Private, on-device document processing is the foundation. Signed receipts and public independent verification are planned for a future edition.
A broader experience.
- Cloud Native & privacy first applications
- On-device verification
- Signed receipts and key verification
- issuer and revocation registry
- Content-change detection
- Accounts and enterprise administration
Our roadmap extends private document provenance across devices and organizations—with pilot partners helping shape the next leap forward.
Evidence, with boundaries.
GrainMark adds a forensic signal to document review through probabilistic grain detection. Content integrity, handwritten signatures and first-print status require separate checks; photocopies can also retain detectable grain.
04 / BUILD WITH US
Put GrainMark
to the test.
Bring your document workflow.
Set the standard for your pilot.
Join as a pilot customer, back development as a founding sponsor, or start an investment conversation. Bring a clear objective. Let’s get to work.
Become a founding partner05 / START A CONVERSATION
Your documents.
Our next chapter.
Tell us where traceability matters to you.
An inquiry is not a purchase or a commitment to join. Please don’t include confidential document content.
Prefer email?
info@0-8.capital
06 / A FEW IMPORTANT DETAILS
Clear answers.
Considered limits.
Developed by Jawed Sarwar for 0–8 Capital GmbH.
What does GrainMark verify today?
The local prototype checks PDFs and scans for expected grain. Detection is probabilistic; it has no independently established detection rate. It does not establish that all document content is unchanged, that a handwritten signature is genuine, or that paper is the first physical print. A photocopy may still validate.
Do my documents leave my device?
The current local edition does not process documents in the cloud. The product vision is to keep document content and verification images on-device, with optional online exchange of non-content issuance records and status checks. Native mobile and tablet applications are planned.
Can anyone independently verify a document?
Not today. Verification is currently limited to the local edition, and private receipts are not cryptographically signed. Independent verification and signed receipts are part of the product vision.
Why use GrainMark alongside electronic signatures?
Signing is one part of a document’s journey. Paper keeps moving afterward.
GrainMark is built for teams that print, distribute and receive documents—and want to reconnect those copies with their issuance context. Its local prototype checks for expected grain, adding a forensic signal to document review.
Use your established signing process. Explore GrainMark where the physical copy matters.
How does GrainMark fit into an existing signing workflow?
GrainMark complements electronic signatures, notarization and legal review. Preserve the original signed PDF: adding marks afterward can invalidate a digital signature or trigger modification warnings.
Can I buy a subscription now?
No. We’re collecting interest in pilots and founding partnerships. €150 per company per month is a pricing hypothesis, not a finalized offer. Usage, included users, enterprise administration and commercial terms are not yet defined.
How is my inquiry information used?
0-8 Capital GmbH uses the contact and workflow details you provide to respond to your GrainMark inquiry. Do not submit confidential documents, scans or keys here. Product updates are optional and require separate consent. This page adds no analytics, advertising trackers or browser storage. Inquiry records are stored privately in encrypted AWS storage in the EU (Ireland), with automatic deletion after 90 days. Submission time and the product-update consent choice are recorded with your inquiry.
See the site privacy policy and company imprint. Contact info@0-8.capital about your information or to withdraw an updates opt-in.