Subnoto
Generate contracts with Carbone, sign them confidentially with Subnoto
Generate the contract. Sign it confidentially. Carbone + Subnoto
Design your contract, NDA, or employment agreement once in Word. Carbone fills it with customer or employee data and renders a clean PDF. Subnoto handles the signature, the audit trail, and the legal proof, all without ever exposing your document to anyone outside the signing parties.
No one can access your data: not Subnoto, not third parties, and not even governments. You stay in control of your data.
Subnoto is the world's first confidential electronic signature solution. It processes every document inside Trusted Execution Environments (TEEs), hardware-isolated secure enclaves where even Subnoto's own infrastructure cannot observe the content, with cryptographically-verifiable attestations that the enclave is genuine. Outside the enclave the document is encrypted at all times. Carbone takes the same approach upstream: documents are rendered, delivered, and deleted, never stored, never analysed. Together, the two products give you a contract pipeline where the only people who ever see the content are the signers themselves.
Why Carbone + Subnoto
Confidentiality by design. Subnoto's TEE-based processing and zero-knowledge architecture keep the document accessible only to its intended signers. Subnoto, third parties, and governments cannot read it, even during signing. Carbone never stores rendered documents either. From data to signature, the content stays with the parties alone.
Plug in anywhere. Both Carbone and Subnoto ship official SDKs, REST APIs, MCP servers, and direct integrations with the major automation platforms. Whatever stack you already use, the pipeline fits (details below).
Sovereign EU stack. Both Carbone and Subnoto are French companies, GDPR-compliant, UETA-compliant, hosted in Europe. Subnoto is rolling out eIDAS advanced and qualified signatures through 2026. If your buyers care about European data sovereignty, this is the only pipeline that delivers it from template to signature.
Your existing templates. Your legal team owns the contract design in Word, Excel, or PowerPoint. Carbone fills it with data. Subnoto signs it. No proprietary editor, no rebuild, no migration cost.
Free to start. No credit card, no commitment. Test the full Carbone + Subnoto flow on the free tiers before you scale.
What you can do with Carbone + Subnoto
- HR onboarding packs. Generate the employment contract, NDA, IP assignment, and remote-work policy from one Carbone template. Subnoto routes them to the new hire, then counter-signs from the CEO with passkey or biometric authentication.
- Personalised contracts at scale. One Carbone template plus 500 customer rows from your CRM equals 500 personalised PDFs handed off to Subnoto's bulk-send flow (template plus CSV).
- Notarial deeds and legal agreements. Word template with
{d.}Carbone tags, personalised deed rendered, then Subnoto handles signing order, signer identity verification, and the certified evidence folder. - SaaS renewal order forms. Every renewing customer gets a Carbone-rendered order form with their negotiated price and terms, sent automatically through Subnoto for counter-signature.
- Real-estate mandates and lease agreements. Pull the property and tenant data from your CRM, render the lease in DOCX with Carbone, push it to Subnoto for tenant and landlord signatures.
- Freelancer engagement contracts and quotes. Stripe payment or HubSpot deal closed, n8n triggers Carbone to render the engagement letter, Subnoto sends it for signature in seconds.
- French public-sector workflows. Subnoto supports Pro Connect, the French government's single sign-on for public-sector users. Combine with Carbone's branded templates for ministry-grade compliant pipelines.
Built for every workflow
Subnoto integrates and collects signatures effortlessly through its web app, TypeScript / Python / PHP SDKs, MCP server, or REST API. Carbone matches that flexibility with SDKs for every major language, a REST API, the Carbone Studio web designer, an MCP server, and direct integrations across the automation ecosystem. Whatever stack you already use, the Carbone + Subnoto pipeline fits.
AI agents that generate and sign within human-defined limits
When an AI assistant calls the Carbone MCP to render a contract and the Subnoto MCP to send it for signature, the question becomes: which contracts can the agent sign, on whose behalf, up to what value, for which counterparties? Subnoto's Delegation Scope feature was built exactly for this, giving you formal, auditable boundaries on what an AI agent is allowed to sign within your organisation. Carbone supplies the templated, deterministic output, Subnoto supplies the legally-binding, scoped signature. Together they are the first end-to-end contract pipeline designed for the AI-agent era.
Any assistant that speaks the Model Context Protocol can run the full generate-and-sign workflow from a single conversation: Claude, ChatGPT, Microsoft Copilot, Vibe by Mistral, Google Gemini, Meta Llama, or DeepSeek. Install the Carbone Skill to teach the assistant Carbone's templating language, and let it call both MCPs to author the template, render the contract, and send it to Subnoto for signature.
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