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# Legal validity of Katalyz signatures

Katalyz signatures are **electronic signatures** suitable for most commercial contracts, NDAs, proposals, order forms, and business agreements.

## Compliance

The Katalyz signature infrastructure is built on standard cryptographic primitives and a tamper-evident sealing flow that meets the baseline requirements for electronic signatures in most commercial contexts. For specific framework compliance (SOC 2, GDPR, HIPAA, regional regulations), please **contact us** with details of your scenario — we'll point you to the latest documentation and supporting agreements available.

## What makes a signature legally binding

Three things, all provided by Katalyz:

1. **Intent to sign** — the signer takes an explicit action to sign (clicking the confirm button, drawing a signature)
2. **Consent to electronic signing** — the signer is informed that they're signing electronically and agrees before starting
3. **A tamper-evident record** — once completed, the PDF is cryptographically sealed. Any modification is detectable by any compliant PDF reader (Adobe Acrobat, Preview, etc.)

These three elements are the widely accepted requirements for electronic signatures to have the same legal weight as handwritten ones in most commercial contexts.

## Authentication levels

Katalyz supports four authentication methods, chosen **per recipient** on the envelope — each signer, approver, viewer or CC can carry a different one. Pick the level that matches the sensitivity of the document and who's on the other end.

| Method | Description | Typical use |
|---|---|---|
| **Email link** | Clicking the link in the email authenticates the recipient. Default. | Standard commercial contracts, proposals, order forms, NDAs |
| **SMS code** | A one-time code sent to the recipient's phone; they enter it to proceed | Higher-assurance contracts where you want a second channel |
| **ID verification** | The recipient verifies their identity with an identity document | Regulated or high-value agreements |
| **Access code** | A code you share with the recipient out of band; they enter it to open the document | When the email inbox alone isn't trusted enough |

## Jurisdictional considerations

Electronic signature laws vary by jurisdiction. The most common frameworks to be aware of:

- **United States** — ESIGN Act (federal) and UETA (state-level) generally recognize electronic signatures for most commercial transactions
- **European Union** — eIDAS regulation defines three tiers: *simple*, *advanced*, *qualified*. Katalyz signatures align with the *simple* tier; for *advanced* or *qualified* use cases (regulated industries, notarial acts), consult your legal counsel
- **United Kingdom** — Electronic Communications Act and similar provisions
- **Other jurisdictions** — most have equivalent frameworks

For standard B2B commercial contracts in most jurisdictions, Katalyz signatures are accepted.

## Situations where Katalyz signatures may not be sufficient

Some document types require specific formats that electronic signatures don't cover (varies by jurisdiction). Common examples:

- Wills and testaments
- Some family law documents (divorce, adoption)
- Some real-estate deeds
- Court filings (often require paper or court-specific e-filing)

When in doubt, consult a qualified lawyer in the relevant jurisdiction.

## Disclaimer

This article is informational, not legal advice. Katalyz provides the technical infrastructure for electronic signing; determining whether a specific use case meets a specific jurisdiction's legal requirements is the responsibility of the signing parties and their legal counsel.

## Related articles
- [Adding a signature widget to a room](https://katalyz.crisp.help/en/article/adding-a-signature-block-to-a-room-u85qg0/)
- [Signature audit trail](https://katalyz.crisp.help/en/article/signature-audit-trail-s3br19/)
- [Downloading a signed document](https://katalyz.crisp.help/en/article/downloading-a-signed-document-6cnhv3/)