How to Prove You Signed an Agreement Without Sharing It

A landlord, a bank or an auditor often needs one fact: that an agreement exists and was signed. Attest's Share proof creates a zero-knowledge proof, verified on zkVerify, that reveals nothing else.

DataHubz
DataHubz
October 30, 2026 · 3 min read
Share
How to Prove You Signed an Agreement Without Sharing It

Our how-to week ends with the most distinctive capability in Attest: proving that you signed an agreement without showing the agreement.

One fact, not the whole document

A landlord, a bank or an auditor often needs one fact: that an agreement exists and was signed. The salary or the price can stay private. A zero-knowledge proof shows that a statement is true without showing the information behind it.

1. Open the completed agreement and choose Share proof

Sign in, open the agreement under the Completed tab and click Share proof.

2. Choose what to prove

Prove that you signed it, or that you and another signer signed it. Each option previews the exact statement before you create anything.

3. Check what the recipient sees

The recipient sees your email address, a co-signer's email address if you name one, the completion date, and that the proof is valid and where it is anchored. The document, its title and any other signer are never shown.

4. Copy the link and send it

Anyone can check the proof free, with no account. The page re-checks it, shows that it is anchored on Base, and links to its independent verification on zkVerify.

On every plan

Share proof is on every plan, Free included, and every signer of a completed agreement also gets a proof made for them automatically. The full guide to sharing proof covers each step.

Sign your first document. Your first 2 documents are free.

Attest is part of the Horizen ecosystem on Base, and its zero-knowledge proofs are verified on zkVerify.

DataHubz

About DataHubz

DataHubz is an AI-powered compliance automation platform that helps organizations achieve and maintain compliance with major cybersecurity and privacy frameworks. We transform complex compliance requirements into continuous, evidence-driven operations powered by structured data management, private AI models, and cryptographic assurance.

Step into the future of compliance.

Prove what you're doing, not just claim it. Build on infrastructure designed for clarity, confidence, and verifiable trust.