# Abundera Sign > E-signatures with cryptographic proof designed to strengthen authenticity and admissibility. PAdES digital signatures, hash-chained audit trails, RFC 3161 timestamps, plain-English document summaries, and public verification. Not just signed. Cryptographically proven. Part of the Abundera platform — private AI that fights for your money. The vanity short-link domain for signing URLs is [asign.ink](https://asign.ink/). ## What Abundera Sign does differently Most e-signature products end at a visual signature and an audit log. Sign produces a cryptographic evidence package: PAdES-compliant digital signatures on the PDF itself, RFC 3161 trusted timestamps, a hash-chained audit trail, and a per-signer verification code any third party can check years later without trusting the platform. ## Core features - **Three-step signing flow** — create via dashboard or API, signers get email links, document returns with full evidence package attached. - **PAdES digital signatures** — Part 4, long-term validation (LTV). Validates in Adobe Acrobat and any PAdES-aware verifier without needing our servers. - **RFC 3161 trusted timestamps** — proof the signature existed at a specific time, from an independent timestamp authority. - **Hash-chained audit trail** — every event in the signing workflow is hash-linked, so tampering is cryptographically detectable. - **Plain-English document summaries** — AI-generated summary of what each signer is agreeing to, so nobody clicks blind. - **Personal Document Seal** — each signer gets a verification code tied to the exact document. Paste it into any TOTP app (Google Authenticator, Authy) and verify the document hasn't changed, offline, any time. - **Public verification** — share a verification URL or code; verifier doesn't need an account. - **31 evidence/identity/workflow/governance features** on every plan — full list in the features section. ## Pricing Plans from $29/mo. No per-seat fees. Full comparison table, API examples, and FAQ on the pricing page. ## Stage / launch US launch: June 1, 2026. Expansion to Canada, UK, Australia, New Zealand, Ireland, and Singapore to follow. Founding Member pricing is available now and locks in a 34% discount forever. ## For developers - API keys, template IDs, signer/field configuration via REST API - OpenAPI 3.0 spec and Postman collection at `/docs/` - Webhooks for envelope lifecycle events (sent, signed, completed, declined) - Short signing links use the `asign.ink` vanity domain ## Canonical links - Home: https://sign.abundera.ai/ - Sitemap: https://sign.abundera.ai/sitemap.xml - security.txt: https://sign.abundera.ai/.well-known/security.txt - Docs: https://sign.abundera.ai/docs/ - Short links: https://asign.ink/ Last reviewed: 2026-04-20