Relex & Claude vs Spellbook
Own your clients, your data and your firm.
Spellbook is an AI copilot for commercial contract drafting and review, living inside Microsoft Word and licensed by seat to in-house teams and law firms. Of the large legal AI products it is the closest to the firms Relex is built for. The difference is scope and ownership. Relex runs the whole matter rather than the document, hands the reasoning to the Claude you already pay for, and keeps client identities out of the model entirely.
At a glance
| Dimension | Relex | Spellbook |
|---|---|---|
| Where client data goes | Encrypted in your browser before anything leaves your device. The model only ever sees [Party 1]. | States that data is not persisted and exists only in memory, with zero data retention agreements with OpenAI and Anthropic, and reports SOC 2 Type II, GDPR, HIPAA and EU AI Act compliance. |
| Whose AI runs it | Bring your own Claude or Claude for Legal over MCP and OAuth. You own the reasoning. | Powered by vendor-selected models, which Spellbook names as including GPT5 and Opus. It does not publicly describe bringing your own model or agent. |
| Try it today | Sign up and run a real case in minutes. Free to try, no card. | A 7-day free trial. Pricing is set by the number of team members on a license and quoted on request. |
| Who owns the client | Partner Network: own the client and keep 100%, at 0% commission. | A channel partner program with revenue share. No marketplace take rate is published. |
| Case structure | A formal ontology of parties, issues, claims, statutes, and facts. | Contract drafting and review inside Microsoft Word. |
| Your know-how | A private per-tenant index the model searches. Never a copy it keeps or trains on. | Your contract history and templates. |
| Getting started | In the browser in minutes, standalone or with your own Claude. | Free trial, then a seat-based license quoted on request. |
This comparison reflects each product’s own public positioning as of July 2026. Spellbook is a trademark of its respective owner, and this page is an independent comparison.
The opposite bet
Spellbook is the bet that the document is the job, so the AI should live where the document lives. Relex is the bet that the matter is the job. The draft is one step between the message a client sent you and the invoice they pay, and all of those steps belong in one place, run by an AI you brought yourself, which never learns who the client is.
Why the pairing wins
Inside a word processor, an AI sees a document and the text you paste around it. Inside Relex, your Claude sees the matter: parties, issues, claims, statutes and facts as a formal ontology, plus your own playbooks and know-how in a private index it can search but never keeps. Connect over MCP and OAuth and it drafts, redlines, flags clause enforceability for you to decide, and records the work, all against labels like [Party 1]. The draft gets better because the model finally knows what the draft is for.
Own the intake, own the client
Clients reach your practice by email, by WhatsApp or SMS message, or through a guest link you send them, and what they tell you becomes a structured case the agent picks up without asking them to repeat it. Intake, drafting, native cryptographic e-signature and invoicing run in one workspace. Through the Partner Network you stay the merchant of record through Stripe, at a flat $99 per month and 0% commission on what your clients pay you.
Relex is a software platform. It is not a law firm, it does not replace lawyers, and it does not provide legal advice.
Questions people ask
Relex or Spellbook for contract drafting?
If you draft inside Microsoft Word all day and that is the whole job, Spellbook is built for exactly that. If the draft is one step in a matter that starts with a client message and ends with a signature and an invoice, Relex runs the whole thing, and lets your own Claude do the drafting against the case structure rather than against a blank page.
Can I bring my own Claude to Spellbook?
Spellbook names the models that power it, including GPT5 and Opus, and does not publicly describe bringing your own model or agent. Relex is built the other way around: you connect the Claude you already pay for over OAuth, with no key to paste, and Relex supplies the structure, the know-how and the privacy boundary.
Does the AI see my client’s name in either product?
In Relex it does not. Names, national IDs and contacts are encrypted in your browser under a password only you hold, documents are de-identified there, and the model works on [Party 1]. If a connected agent asks the server for plaintext personal data, the request is refused and a deep link is returned so you can do that step yourself. Spellbook publishes its own data-handling claims, including zero data retention agreements with OpenAI and Anthropic.
What does Relex cost?
Signing up is free with no credit card. Per-case and subscription pricing is shown live on the pricing page. The Partner Network is a flat $99 per month with 0% commission on client payments, and you are the merchant of record through Stripe.
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Automate the work around the law. Stay the lawyer.
Own your clients, your data, and your firm. Start in the browser, or bring your own Claude in one step. No key to paste.