Terms of Service

Last Updated: July 24, 2026

1. Acceptance of Terms

By accessing and using kysigned services, including our website (kysigned.com), API, and related tools, you agree to be bound by these Terms of Service ("Terms"). If you do not agree to these Terms, please discontinue use of our services immediately.

2. Description of Service

kysigned is an signing-record e-signature service provided by Kychee, Inc. ("Kychee," "we," "us," or "our"). Our services include:

• Creating and managing electronic-signature requests ("envelopes") for PDF documents
• Collecting each signer's signature in the form of an email that the signer's own email provider cryptographically signs (a DKIM signature)
• Assembling a self-contained signing record — a single PDF containing the document, a signature page, each signer's original signed email, independent timestamp proofs, and the relevant public keys
• Delivering that signing record to every party and providing a tool to verify it
• Hosting the working copy of a document for a limited retention period
• Providing an API, MCP server, and dashboard for managing signatures

The evidence is the signing record itself. A signer's signature is an ordinary email that the signer's own email provider cryptographically signs (a DKIM signature) — kysigned collects that signed email, anchors its time, and packages it. Anyone can verify the signing record independently using public mathematics and public key archives, with no continued reliance on Kychee.

kysigned is available as a hosted service at kysigned.com and as an open-source repository (Apache 2.0 license) that third parties may deploy independently.

3. What a Signature Proves

A kysigned signature is cryptographic evidence that someone with control of a specific email mailbox sent a specific document with the intent line "I sign this document" at a specific time. It proves control of mailbox X over document Y — it does not prove the identity of the person operating the mailbox. Mailbox compromise (unauthorized access to the email account) is a known and inherent limitation of any email-based signature.

kysigned does NOT guarantee:

• That the person who signed is who they claim to be
• That the signer read, understood, or agreed to the document contents
• That the signer had legal capacity or authority to sign
• That the signature is legally binding or enforceable in any specific jurisdiction
• That the signature satisfies the requirements of any particular law, regulation, or contract

The evidentiary value of a kysigned signature depends on the context and jurisdiction.

4. Electronic Signature Law

4.1 United States (ESIGN Act / UETA)

The signer's DKIM-signed forward, sent in response to a signing request that discloses the consent-to-electronic-business notice (presented on the document cover page and in the signing-request email), is intended to satisfy the "intent to sign" and "association with the record" requirements of the federal ESIGN Act and the Uniform Electronic Transactions Act (UETA). The specific consent-language version presented to each signer is recorded for that document at signing time.

4.2 European Union (eIDAS)

A kysigned signature is, by definition, at least a Simple Electronic Signature (SES) under Regulation (EU) No 910/2014 (eIDAS). We further design the service to meet the four properties of an Advanced Electronic Signature (AES) under Article 26, argued on the DKIM substrate: the provider's signing key is uniquely associated with the signatory's mailbox; the From header identifies the signatory; signing requires sole control of the mailbox; and any later alteration of the data is detectable through byte-level tamper evidence.

kysigned is NOT a Qualified Trust Service Provider and does NOT produce Qualified Electronic Signatures (QES). We make no QES claim. Documents that require a QES, notarization, witnessing, or attestation by a public official under applicable law are outside the intended use of kysigned (see Section 8 and the Acceptable Use Policy).

4.3 Your Responsibility

Electronic-signature law varies by jurisdiction and document type. You are solely responsible for determining whether an electronic signature is legally valid for your document, your jurisdiction, and any jurisdiction where the document will be used or enforced. kysigned does not provide legal advice.

5. Authentication

5.1 Creator Sign-In

Senders sign in to kysigned.com using a passkey or an email magic link; there is no password to manage. You are responsible for securing your passkey device and access to your email account.

5.2 Signers

Signers do not register, hold an account, or sign in. A signer participates solely by forwarding the signing-request email from their own mailbox.

5.3 Account Security

You are responsible for maintaining the security of your authentication method and for all activities conducted under your identity.

6. Prepaid Credits

6.1 Purchase and Use

Creators buy prepaid credit packs by credit or debit card. Card payments are processed by Stripe, our third-party payment processor, on Stripe's own secure checkout pages — kysigned never receives or stores your card details. Credits are deducted when a document is sent for signing. Credit packs are non-refundable except as required by applicable law; a credit consumed by a document that is voided before any signature is recorded is returned to your balance. If you close your account, any remaining credit balance is forfeited and is not refunded.

6.2 Credit Expiry

Credits do not expire.

6.3 Pricing

Per-document pricing is displayed at the time of purchase. We reserve the right to change pricing for future credit pack purchases with 30 days' notice.

7. Document Handling and Retention

7.1 Ephemeral Storage

The working copy of an uploaded PDF is retained only as long as operationally required — through the active signing period and until the completed signing record is confirmed delivered to all parties — and is then permanently deleted. If a completion email bounces, the document is retained for up to 7 additional days while delivery is retried. No working copy is retained longer than 30 days from completion, regardless of delivery state. In practice documents typically exist in storage for hours, not days. After deletion, only metadata (document name, document hash, signer statuses, signing timestamps) persists.

7.2 Proof in Your Inbox

The permanent record of a completed signing is the signing record delivered to your inbox, not anything Kychee retains. Once the signing record has been delivered, Kychee does not need to — and after the retention window cannot — regenerate it. Keep your copy of the signing record; its validity does not depend on kysigned continuing to operate.

7.3 The Signed Emails

Each signer's signature is the email they forward. The complete, original signed email is embedded inside the signing record delivered to every party, where it remains independently verifiable. During the active signing period the signed email is held by our email infrastructure provider only as long as needed to assemble the signing record.

7.4 User Notification

You are notified of the retention policy when you send a document, in the completion email, and (where applicable) before document deletion.

8. Acceptable Use

Your use of kysigned is subject to our Acceptable Use Policy, which is incorporated by reference. Among other things, you agree not to use kysigned to:

• Send signing requests that are unsolicited, deceptive, or fraudulent, or to anyone who is not expecting your document — a severe violation that may result in immediate revocation of your account and a report to the appropriate authorities
• Sign a document type that is excluded from electronic signature under applicable law (the Acceptable Use Policy lists non-exhaustive examples, including wills, codicils, testamentary trusts, and documents requiring notarization, witnessing, or a court-appointed official)
• Forge, misrepresent, or impersonate the identity of a signer, or add signers without their knowledge
• Upload documents containing malware or malicious content
• Violate any applicable law or regulation, or use the service for any illegal purpose
• Harass, abuse, or harm other users or signers
• Attempt to circumvent security measures or access data you are not authorized to access

9. Intellectual Property

The kysigned hosted service (kysigned.com), including its design, branding, and proprietary features, is owned by Kychee, Inc. The kysigned core library is released under the Apache License 2.0 — see the public repository for details.

10. Third-Party Services

Our service relies on third-party providers, including run402 (compute, database, email, and storage infrastructure), Stripe (card payment processing), email delivery providers, and public timestamp authorities and DKIM-key archives used to make signatures independently verifiable. Your use of such services is governed by their respective terms. We are not responsible for the practices or policies of third parties.

11. Disclaimer of Warranties

THE SERVICE, INCLUDING ALL SIGNING RECORDS AND VERIFICATION RESULTS, IS PROVIDED ON AN "AS-IS" AND "AS-AVAILABLE" BASIS. TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, WE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ACCURACY, RELIABILITY, AND AVAILABILITY.

WE DO NOT WARRANT THAT ANY THIRD-PARTY EMAIL PROVIDER, TIMESTAMP AUTHORITY, OR PUBLIC KEY ARCHIVE WILL REMAIN AVAILABLE, OR THAT A GIVEN SIGNATURE WILL BE ACCEPTED AS EVIDENCE BY ANY COURT OR COUNTERPARTY.

12. Limitation of Liability

TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, IN NO EVENT SHALL KYCHEE, INC., ITS AFFILIATES, LICENSORS, OR SERVICE PROVIDERS BE LIABLE FOR ANY INDIRECT, INCIDENTAL, CONSEQUENTIAL, SPECIAL, PUNITIVE, OR EXEMPLARY DAMAGES, INCLUDING BUT NOT LIMITED TO LOSS OF PROFITS, DATA, GOODWILL, BUSINESS INTERRUPTION, OR RELIANCE ON ANY SIGNATURE OR VERIFICATION RESULT, ARISING OUT OF OR RELATED TO YOUR USE OF THE SERVICE.

OUR TOTAL LIABILITY FOR ALL CLAIMS ARISING OUT OF OR RELATED TO THE SERVICE SHALL NOT EXCEED THE AMOUNT YOU PAID TO US IN THE TWELVE (12) MONTHS PRECEDING THE CLAIM.

13. Indemnification

You agree to defend, indemnify, and hold harmless Kychee, Inc. from any claims, liabilities, damages, losses, costs, and expenses arising out of or related to: (a) your use of the service; (b) documents you submit for signing; (c) your violation of these Terms; (d) your violation of any third-party rights; or (e) any legal proceedings related to documents signed through the service.

14. Modifications to Service

We reserve the right to modify or discontinue the service with or without notice. If we discontinue the service, signing records already delivered to you remain valid and independently verifiable — their verification does not depend on kysigned.com remaining online.

15. Termination

We reserve the right to terminate or suspend your access at our sole discretion for conduct that violates these Terms.

16. Dispute Resolution

16.1 Informal Resolution

Before filing any formal legal proceeding, you agree to attempt to resolve any dispute with us informally by contacting legal@kychee.com with a written description of the dispute. We will attempt to resolve the matter within sixty (60) days. If the dispute is not resolved within that period, either party may proceed under Section 16.2.

16.2 Governing Law and Jurisdiction

These Terms shall be governed by the laws of the State of Delaware, United States, without regard to conflict of law principles. Disputes that are not resolved informally under Section 16.1 shall be resolved exclusively in Delaware state or federal courts.

17. Changes to Terms

We may modify these Terms at any time. Material changes will be communicated via email and/or posted on our website at least thirty (30) days before taking effect. Continued use constitutes acceptance.

18. Severability

If any provision is held invalid, the remaining provisions continue in full force.

19. Entire Agreement

These Terms, together with our Privacy Policy, Acceptable Use Policy, and Cookie & Consent Notice, constitute the entire agreement between you and Kychee, Inc.

20. Contact

Kychee, Inc. Email: legal@kychee.com General inquiries: info@kychee.com