Casetext (CoCounsel) vs LexisNexis Protégé

One side of this comparison is not a product you can buy. Casetext was retired on April 1, 2025: Thomson Reuters acquired it in 2023 for $650M, began redirecting casetext.com on February 1, 2025, and shut the standalone platform down two months later. The CoCounsel skills survived — they ship today inside Thomson Reuters CoCounsel, sold per attorney against the Westlaw corpus. So the live head-to-head is CoCounsel versus LexisNexis Protégé, and that platform bake-off is covered at LexisNexis Protégé vs Thomson Reuters CoCounsel. This page answers the narrower question the retirement left behind: a former Casetext subscriber, or someone who found Casetext on a review site with live pricing attached, deciding where a roughly $200/user/month self-serve seat goes in 2026.

What died was the checkout, not the assistant

The eight-skill CoCounsel assistant is alive and shipping faster than it did under Casetext. Thomson Reuters launched CoCounsel Legal on August 5, 2025 with Deep Research — an agentic research mode that builds a plan, works it across Westlaw and Practical Law, and returns a memo with a visible reasoning chain. In January 2026 it launched in the UK. In June 2026 every US customer got a rebuilt chat surface behind an in-product toggle — it drafts a plan before it answers — plus Deep Research Verify, which checks whether cited authority actually supports the assertion it is attached to rather than only confirming the citation exists.

What did not survive is the buying motion. A solo attorney used to put a card into a checkout page and be working the same afternoon with no Westlaw contract and no procurement cycle. Both surviving options are quote-led research platforms with the AI priced on top. That is the real content of this comparison, and it is why the answer is not the same as the enterprise answer.

Where the CoCounsel line wins for a former Casetext buyer

• Skill continuity. Document review, deposition prep, contract analysis, and research memos keep the same shape and the same output format. Nobody retrains. For a two-partner shop with billable hours to protect, that is worth a real premium over a lateral move.
• Deep Research Verify closes the sanctions gap. Launched June 2026, Westlaw-native first, it flags misattribution — a cite that exists but does not stand for the proposition. Citation-existence checks do not catch that class of error.
• It is the only one of the two with a price you can see. Thomson Reuters sells online to firms up to 10 attorneys. Above that, it is a sales cycle. For the segment Casetext served, that ceiling is the whole market.
• Non-US research is now in the product. A June 2026 international legal research skill covers France and Germany including EU law, on top of the January 2026 UK launch.

Where Protégé wins

• Shepard’s Verify Trust Markers scan attorney-drafted text too. Shipped May 7, 2026, they check citations in AI-generated and human-written passages against LexisNexis sources and flag any that cannot be verified as existing. CoCounsel’s equivalent runs on its own output.
• Matter-grounded drafting at volume. Protégé Vault holds up to 100,000 documents per vault and ingests PDFs, spreadsheets, images, audio, and video, with outputs linking back to the source passage. Protégé Work routes a plain-language goal across LexisNexis-developed and Anthropic-powered skills; Workrooms add role-based permissions, dual approvals, and audit trails across firm, client, and co-counsel.
• You can hold your own encryption keys. Protégé BYOK integrates with AWS KMS, Azure Key Vault, Google Cloud KMS, and HashiCorp Vault, and LexisNexis reports deployments in AmLaw 100 firms. Thomson Reuters has no equivalent customer-held-key option in CoCounsel Legal.
• Per-use pricing exists. LexisNexis sells transactional access at roughly $99 per AI Ask and $250 per AI Drafting use (third-party reported). It is the only remaining way to buy grounded legal AI without committing to seats, and it is the closest structural echo of what Casetext buyers actually liked.

Pricing: the multiple that decides this

Casetext sold standalone from roughly $200/user/month with self-serve solo and small-firm tiers. Set that as the baseline.

Thomson Reuters publishes its small-firm number. Westlaw Advantage with CoCounsel Essentials runs $639/user/month for a solo attorney on All States & Federal coverage at a one-year term, dropping to about $519/user/month on a three-year term; the term discounts are 12% at two years and 18% at three. That is a 2.6x to 3.2x increase over the old Casetext rate. A five-attorney firm lands at roughly $2,597–$3,196/month, or $31,161–$38,352/year, per a June 2026 third-party configurator snapshot.

LexisNexis publishes nothing. Third-party reporting puts the Protégé AI add-on at $125–$275/user/month on top of an existing Lexis contract, and a full standalone Lexis+ with Protégé bundle at $128–$494/user/month, with enterprise configurations carrying the complete agentic feature set quoted above that band. Treat every one of those figures as directional; none is vendor-published.

The number that decides it: Protégé’s floor sits under CoCounsel’s published solo rate only if you already pay for the Lexis library. If you are net-new to both, the Lexis add-on band is not the number you will be quoted — you will be quoted the bundle, and you will find it out inside a sales cycle rather than on a pricing page.

Verdict

Pick the CoCounsel line when Westlaw is already a line item, the practice is litigation- and research-heavy, associates already work in the CoCounsel skills, or the firm is at or under 10 attorneys and wants to buy this week without a procurement cycle. You are buying continuity, and continuity is the only thing here with a visible price.

Pick Protégé when you are on a Lexis contract, cite-checking needs to cover what your attorneys write and not only what the model writes, matter-grounded drafting across large document sets is the actual workload, you are regulated enough to need customer-held encryption keys, or you want per-use pricing instead of seats.

If you cannot decide, buy the AI attached to the research database you already pay for. Cross-buying means paying twice for the underlying corpus, which is the asset in this market — the model layer will commoditize faster than the content layer. If you pay for neither database, start with CoCounsel: it is the only side of this with a bounded, public number below 10 attorneys.

If neither fits, you valued the checkout rather than the corpus. Spellbook covers transactional drafting and review inside Word at a price closer to what Casetext charged; Legora is the content-agnostic drafting and review alternative; Claude handles summarization and analysis of documents you supply. Guard: none of the three does primary-law research with citation validation, so route anything that will be filed through a Shepard’s or KeyCite check before it leaves the firm.

Two things to watch

• The Casetext brand outlived the product by more than a year. Review sites, procurement spreadsheets, and comparison articles still list Casetext with a live $200 price attached. None of it is buyable. Guard: verify against thomsonreuters.com before Casetext enters a shortlist or a budget line.
• Renewal is where the migration cost actually lands. Former Casetext subscribers moved onto Thomson Reuters paper have reported being placed on fixed-term promotional rates with no guaranteed renewal number. Guard: get the post-promotional renewal rate in writing at signature, not at renewal.