Legal Practice
Court-defensible signatures with cryptographic proof
Engagement letters, retainers, and settlements signed with PAdES cryptographic signatures, blockchain anchoring, and public verification — all standard, no upcharge.
Templates ready to send
Engagement Letter
Scope, fees, retainer, and conflict-check language.
Retainer Agreement
Trust account terms with monthly billing flow.
Settlement Agreement
Multi-party signing with witness + counter-sign roles.
Bill retainers + final invoices in one place
Connect signed engagement letters to SilverInvoice. Trust-account-aware billing with Canadian tax handling and Stripe-powered card collection. Audit-ready exports for LawPRO compliance.
See SilverInvoice →Common questions
Are SilverDoc signatures admissible in Canadian courts?
Yes. Each signed document includes (1) tamper-evident SHA-256 hash, (2) PAdES cryptographic signature visible in Adobe Reader, (3) blockchain anchor via OpenTimestamps, and (4) full audit trail with IP, timestamp, and optional identity verification. This satisfies provincial e-signature legislation including Ontario's ECA and Quebec's LCCJTI.
What's the difference between PAdES signatures and basic e-signatures?
PAdES (PDF Advanced Electronic Signatures) embeds a cryptographic signature in the PDF itself, mathematically verifiable in any PDF reader. Basic e-signatures are just visible images plus an audit trail. Both are legally valid in Canada; PAdES adds a defense-in-depth layer that's especially valuable for documents likely to be challenged.
Can opposing counsel verify a settlement signature without contacting us?
Yes. Each document has a 12-character certificate number printed on the audit page. Visit thesilverfern.ca/verify/{number} — anyone can confirm the document exists, see the signers (names only, no privileged information), and verify the SHA-256 hash matches.
How does the blockchain anchoring work?
On signing completion, the SHA-256 hash of the signed PDF is submitted to OpenTimestamps, which aggregates submissions and commits them to a Bitcoin transaction within ~1 hour. The proof is included in the audit certificate. This provides a court-admissible third-party timestamp without relying on us.
What's your retention and deletion policy?
Documents are retained indefinitely by default. Customers can configure per-document retention or trigger a GDPR/PIPEDA-compliant hard-delete. Cryptographic hashes (used for verification) persist even after content is deleted, so verification remains possible without the document content.
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