ThoughtRiver

ThoughtRiver is an AI contract pre-screening and review platform for in-house legal teams and the law firms that serve them. Its engine reads a contract and answers a network of legal questions the vendor calls Lexible, some 2,500 pre-trained questions built by its in-house lawyers since 2016 and, in the current version, run on a proprietary generative model layered on several large language models; the answers are scored against the customer's own playbook or the vendor's default policies to produce a risk rating, a Digital Issues List of every point that needs resolving, suggested redlines and a remediation workflow inside Microsoft Word, with a Lexible Assistant for questions about any contract and portfolio-level analysis across large volumes of agreements. The company is ThoughtRiver Ltd of Cambridge, England, whose customers and partners include Shoosmiths, which reports the platform reviewing complex supply agreements in under three minutes at above ninety per cent accuracy. Its published data processing addendum lists processing purposes that include machine-learning training and feature enhancement, names five sub-processors with Microsoft Azure hosting in the United Kingdom, and commits to breach notification without undue delay and deletion or return of personal data on termination; its security page states ISO 27001 certification with a certificate number, per-customer segregation under a unique encryption key, hosting in a single specified Azure region, and multi-factor and single sign-on through Auth0.

Vendor siteCambridge, England, United Kingdom
Last verifiedSeptember 6, 2026

Capability grades

All 15 axes, graded from public sources on the date shown. Hover a grade to see what the letter means on that axis.

AA on AI CentralityThe artificial intelligence is the product. Remove the models and there is nothing left to sell.

AI Centrality

How much of the product is actually AI. Whether the machine learning is the mechanism the buyer is paying for or a feature layered onto conventional software, and whether the vendor is specific about which is which.

The machine learning is the mechanism the buyer pays for. The product is contract pre-screening: a model reads the contract, answers the Lexible question set, scores the answers against a playbook and produces the risk rating, issues list and suggested redlines; remove the models and there is no review, no issues list and no redlines, only a document store. The vendor has sold this as an AI product since 2016 and describes the current engine as a proprietary generative model on several large language models. Home page, demo page and platform description read 6 September 2026.

Source: Vendor Published
BB on Citation Accuracy and Hallucination DisclosureGrounding is real and documented, with linked primary sources and a described retrieval method, short of published accuracy figures an outsider can test.

Citation Accuracy and Hallucination Disclosure

Whether the vendor publishes measured accuracy on citations and assertions, grounds output to primary sources, and says plainly what its system does when it does not know. Legal has a documented public record of fabricated citations reaching filed briefs, so an untested claim of accuracy is not evidence.

A measured accuracy figure is published, short of a described test set and named failure modes. The demo page states 97.3 per cent accuracy across 2,500 pre-trained questions and an average review time of 8.2 minutes, and a Shoosmiths partner is quoted that the platform reviewed complex supply agreements in under three minutes at above ninety per cent accuracy against qualified lawyers at 86 per cent over four hours; no test set, method, date or failure-mode statement accompanies either figure on the surfaces read. An Accuracy page exists in the navigation and was not opened, and would lift this to A if it describes the test set. The primary-authority limbs do not apply to a contract reader. Demo page and home page read 6 September 2026.

Source: Vendor Published
BB on Autonomy and Oversight ModelA written commitment that the models work alongside a supervising lawyer, with real review surfaces, short of the full control structure: commonly the threshold at which the system stops or what happens after it is wrong.

Autonomy and Oversight Model

What the system decides on its own, what a lawyer must approve, and whether the vendor documents where the review point sits. A tool that drafts under review and a tool that files without one are different products and different risks.

The modes and the review surface are published, short of the full control structure. The product runs the review and produces a Digital Issues List with a risk rating for every contract, routes and prioritises matters on that basis, and presents suggested redlines for a lawyer to accept inside Word; the playbook a customer configures sets what is flagged, and the vendor describes the product's purpose as automating routing and prioritisation decisions in busy legal functions. What is not published is the threshold at which a contract is treated as clear without human review, or a stated route back after a wrong answer beyond the reviewer's own correction. Home page, G2 feature description and platform coverage read 6 September 2026.

Source: Vendor Published
BB on Operational and Outcome EvidenceReal deployment evidence with substance, short of full attribution or measurement: a named customer without figures, or figures without the named customer.

Operational and Outcome Evidence

Named, dated evidence that the product works in production at real firms or legal departments. Case studies with figures and identified customers count. Unattributed testimonials and launch announcements do not.

A named customer with figures, short of a date and method. Joe Stephenson, partner and head of technology at Shoosmiths, is quoted on the vendor's demo page that the platform reviewed complex supply agreements in under three minutes at above ninety per cent accuracy where qualified lawyers took four hours at 86 per cent; a second customer is quoted, unnamed, that ThoughtRiver was a clear winner for reviewing its appointments. No date, sample size or method accompanies the Shoosmiths figures. Demo page and home page read 6 September 2026.

Source: Vendor Published
CC on Privilege and Confidentiality PostureConfidentiality is asserted in general terms, or the commitment lives only in a sales conversation and cannot be read in advance.

Privilege and Confidentiality Posture

How client confidences are handled: attorney client privilege and work product treatment, segregation of one client matter from another, whether client data trains any model, and what the vendor commits to in writing rather than in marketing.

Segregation and encryption are substantive, and the training position is adverse, which is the finding. The security page states that contract documents and derived data are segregated from other customers and encrypted with a unique key per account, and the DPA deletes or returns personal data on termination. Against that, the DPA annex lists machine-learning training and feature enhancement among the purposes for which uploaded contract data is processed, with no opt-out located, and the published sub-processor table names no language-model provider while the demo page states the engine is built on several industry-leading LLMs, so who receives contract text for inference is not stated. Nothing addresses privilege or work product. DPA, security page and demo page read 6 September 2026; the terms of use were not opened.

Source: Vendor Published
CC on UPL and Professional Responsibility PostureA boilerplate disclaimer sits in the terms while the marketing describes the product in advice terms, or the intended audience is left ambiguous.

UPL and Professional Responsibility Posture

Whether the vendor is clear that it supplies a tool rather than legal advice, who its audience is, and how it addresses unauthorized practice of law, competence and supervision duties, and jurisdiction limits. ABA Formal Opinion 512 is the reference point.

No advice line or supervision statement was located on the surfaces read. The product is marketed as delivering detailed advice that guides users through remediation and as serving in-house counsel, business and procurement teams, without a located statement that outputs are not legal advice or that a qualified lawyer should supervise them; the terms of use exist in the footer and were not opened, and are the rebuttal route. Home page and platform descriptions read 6 September 2026.

Source: Vendor Published
CC on AI Governance and Bias DisclosureResponsible AI principles are published without a mechanism, a testing regime, or anything a buyer could audit.

AI Governance and Bias Disclosure

Published governance over model behaviour: who owns it inside the vendor, what is tested before release, and what is disclosed about disparate output across matter types, parties, or populations.

An AI-regulation statement exists and was not read, and no framework, testing regime or accountable owner was located on the surfaces read. The footer links a document titled the EU AI Act and how it relates to ThoughtRiver, which was not opened and is the rebuttal route; the demo page states continuous training by in-house lawyers since 2016, which is a development practice rather than a governance disclosure. No ISO 42001 or equivalent, pre-release testing description or statement about uneven output across contract types was located. Footer, demo page and home page read 6 September 2026.

Source: Vendor Published
BB on AI Safety and Data StewardshipSubstantive published policy covering most of the ground, short of the full set: commonly no named subprocessor list or no stated incident practice.

AI Safety and Data Stewardship

Retention, deletion, access control, and what happens to prompts and documents after they are processed. Whether the vendor states its subprocessors and its incident practice, or leaves the buyer to assume.

Substantive published policy covering most of the ground, with one gap. Retention and deletion: the DPA deletes or returns personal data on termination unless backed up or legally required, with no period stated for backups. Access control: Auth0 authentication with single sign-on and multi-factor, TLS 1.2 in transit, encryption at rest under a per-customer key, a web application firewall. Sub-processors: a published table of five with location, data categories and operations and the transfer mechanism for the one outside the UK and EU. Incident practice: the DPA commits to breach notification without undue delay. The gap is that the sub-processor table names no language-model provider while the product is stated to run on several, and the security page states no external processors are used for customer data. DPA and security page read 6 September 2026.

Source: Vendor Published
DD on AI Liability and RecourseNothing published on who bears the loss when the system is wrong.

AI Liability and Recourse

What the vendor stands behind contractually when its output is wrong. Indemnities, caps, carve outs, insurance, and whether any of it is published or only reachable through a negotiated agreement.

No liability position was located on the surfaces read. The DPA addresses processor obligations and audit rights without an indemnity, cap, warranty or insurance position, and the security page describes controls; the terms of use, linked in the footer, were not opened on 6 September 2026 and are the rebuttal route that would replace this grade on a read. This records what is locatable on the date and not a finding that no position exists. DPA and security page read 6 September 2026.

Source: Operator Verified
CC on Practice Systems Integration DepthIntegrations are listed as logos or marked as coming, with no documentation an implementer could use.

Practice Systems Integration Depth

How deeply the product reaches into the systems legal work already lives in: document management such as iManage and NetDocuments, Word and Outlook, contract lifecycle management, matter management, e-billing, and court filing systems.

Integrations are referred to without documentation an implementer could use on the surfaces read. The vendor describes remediation inside Microsoft Word and an Integrations and Security page exists in the navigation; iManage, HighQ, Outlook and Power BI are named by a third-party directory and are not credited. Nothing read describes what syncs or in which direction. Home page and navigation read 6 September 2026; the integrations page is the rebuttal route.

Source: Vendor Published
BB on Deployment Model and Data ResidencyDeployment model is stated clearly with partial residency detail, or residency is offered without the processing location being addressed.

Deployment Model and Data Residency

Where the software runs and where the data sits. Multi tenant cloud, single tenant, private deployment, on premises, and whether region of residence is a published option or an enterprise conversation.

Region and processing location are stated and the tenancy model is described as segregation. The security page states that data resides in Azure data centres managed and secured by ThoughtRiver in a single specified region, and the sub-processor table places Azure hosting in the United Kingdom; contract documents and derived data are segregated per customer under a unique key. Whether a customer may elect a region other than the UK, and whether infrastructure is shared, are not stated, and the inference location for the language models is not addressed. Security page and DPA read 6 September 2026.

Source: Vendor Published
BB on Security Certifications and Trust CenterCertification is real and stated, short of accessible evidence: a named standard without scope, date, or a way to obtain the report.

Security Certifications and Trust Center

Independent attestation a buyer can pull without a sales call: SOC 2, ISO 27001, penetration test summaries, a trust center with current reports and named scope rather than a badge image.

Certification is real and identified by number, short of a report route. The security page states ISO 27001 certification under certificate number 21188-ISMS-001, with encryption at rest and in transit, a web application firewall, per-customer keys and Auth0 multi-factor authentication. No certifying body, coverage period or route to the certificate or any SOC report is published, and no trust centre was located. Security page read 6 September 2026.

Source: Vendor Published
CC on Model Supply Chain DisclosureThe vendor refers to advanced or proprietary models without identifying what sits underneath.

Model Supply Chain Disclosure

Which models sit underneath, whose they are, where they run, and whether the vendor commits to telling customers when that changes. A legal buyer inherits every dependency it cannot see.

The vendor refers to the models without identifying what sits underneath, and its own documents disagree. The demo page states the proprietary Lexible generative model is built upon several industry-leading LLMs, the sub-processor table names no language-model provider, and the security page states that no external processors are used for customer data; a separate marketing statement refers to a zero-data-retention policy with AI partners. No provider, model, inference location or change-notification commitment is named, and the contradiction is the finding a buyer would need resolved. Demo page, security page and DPA read 6 September 2026.

Source: Vendor Published
CC on Commercial TransparencyPricing is gated behind a demo request while tier names and feature splits are published, so the shape is visible and the number is not.

Commercial Transparency

Whether a buyer can learn what this costs without entering a sales process: published rates, the unit being charged, what sits behind an enterprise tier, and what implementation adds.

A free tier is published and the paid figure is not on the surfaces read. The home page offers a free 28-day trial and a pricing page exists in the navigation; the pricing page was not opened on 6 September 2026 and is the rebuttal route in either direction. No unit of charge, tier or figure appears in the material read. Home page and navigation read 6 September 2026.

Source: Vendor Published
BB on Firm and Practice CoverageSegment and practice coverage is described with substance, short of the boundaries: what is supported is clear, what is not is left open.

Firm and Practice Coverage

Who the product is actually built for. AmLaw, midlaw, small firm and solo, in house departments, government and courts, and which practice areas are supported rather than merely claimed.

Segment and coverage are described with substance; the boundaries are partly stated. The buyer is in-house legal with business and procurement users, and law firms as partners and customers; the question set is stated at 2,500 pre-trained questions with playbooks configurable per customer, and the company has operated from the United Kingdom since 2016 with Azure hosting there. The vendor states the product is trained by its in-house lawyers, which fixes its coverage to the contract types those questions address; no contract type or jurisdiction is named as unsupported on the surfaces read. Demo page, home page and DPA read 6 September 2026.

Source: Vendor Published

Legal Signals

What each signal means

A signal records what public sources say on the date shown. It is not a grade and it is not a recommendation. Where a signal reads Not addressed, it means the index did not locate the material in public sources on that date, which is a statement about disclosure rather than about the product.

Confidentiality and Privilege

Client Data in Training

Can material a lawyer puts into this product be used to train a model?

Permitted, in the contract

The published agreement expressly reserves a right to train on customer content, with no opt out located. Any de identification, anonymisation or aggregation qualifier is recorded in the summary.

The published agreement names machine-learning training as a purpose for which customer data is processed, and no opt-out was located. The data processing addendum's annex states that processing of personal data uploaded in documents includes contract risk review, data extraction, ML training, feature enhancement and customer support, and its fuller text describes training of properties created within the platform and product feature enhancement. Two readings are carried: training of the Lexible properties a customer configures on its own contracts, which is the product working for that customer, and product feature enhancement generally, which is training for the vendor's benefit; the clause covers both. A vendor marketing statement refers to a zero-data-retention policy with AI partners so that customer data is never used to train AI models, which concerns the model providers rather than ThoughtRiver's own use; the agreement governs. Surfaces checked 6 September 2026.

Source: Vendor PublishedProcessing includes contract risk review, data extraction, ML training, feature enhancementAs of Sep 6, 2026Evidence

Prompt and Output Retention

How long does the product keep what a lawyer typed, and can that be set to zero?

Disclosed without a period

Retention is acknowledged in public materials with no stated period.

Retention is acknowledged without a period. The DPA commits to delete or return personal data on termination except where it is held in backups or law requires retention, with no backup retention period stated and no statement about prompts or outputs during the term; the marketing reference to zero data retention with AI partners concerns the model providers. Surfaces checked 6 September 2026.

Source: Vendor Publisheddelete or return all Personal Data unless backed up or required by law to retain itAs of Sep 6, 2026Evidence

Ethical Walls and Matter Segregation

Does retrieval respect the firm’s ethical walls, or can the model read across them?

Own model, documented

The product maintains its own permission model, documented, requiring the firm to keep it aligned.

The product maintains its own separation model and documents it at customer level. The security page states that contract documents and derived data are segregated from other customers and encrypted with a unique key specific to the account, with authentication through Auth0 single sign-on and multi-factor. Nothing describes walls between matters or teams within a customer, and no document management system's access model is inherited. Surfaces checked 6 September 2026.

Source: Vendor Publishedsegregated from other customers and encrypted with a unique key specific to your accountAs of Sep 6, 2026Evidence

Third Party Request and Subpoena Notice

If someone subpoenas the vendor for a firm’s data, does the firm hear about it first?

Notice committed

Terms commit to notice where lawfully permitted. No transparency report located.

The published DPA commits to inform the customer where law requires ThoughtRiver to process personal data contrary to the customer's instructions, unless prohibited by law, which is the shape of a compelled-disclosure notice for personal data in uploaded contracts. The commitment is narrower than a general legal-process clause: it is framed around processing instructions and personal data, and the terms of use, where a broader clause would sit, were not opened on 6 September 2026 and are the rebuttal route. No transparency report is published.

Source: Vendor PublishedWhere required by law to process contrary to instructions, ThoughtRiver will inform the Customer unless prohibited by lawAs of Sep 6, 2026Evidence
Accuracy and Authority

Primary Law Corpus Provenance

Where does the law in this product come from, and does the vendor have the right to use it?

Not addressed

No located public material identifies the corpus behind the product’s answers.

No located public material identifies a legal corpus behind the product's answers, and the product is not built on one: the engine answers the vendor's own Lexible question set, described as 2,500 questions authored and trained by its in-house lawyers since 2016, against the customer's contract text. The questions are the vendor's own work rather than licensed law, and no primary law source or update cadence is stated. Demo page and home page checked 6 September 2026.

Source: Operator VerifiedAs of Sep 6, 2026

Good Law Verification

Does the product tell you when the authority it just cited has been overruled?

Not addressed

No located public material addresses whether authority is checked for subsequent history.

No located public material addresses whether authority is checked for subsequent history, and the product does not retrieve or cite primary law; its output is risk ratings, issue lists and redlines on the customer's contract. Recorded as the honest value for a product without a citator function. Surfaces checked 6 September 2026.

Source: Operator VerifiedAs of Sep 6, 2026

Refusal and Uncertainty Behaviour

What does the product do when the answer is not in the corpus?

Not addressed

No located public material addresses what the product does when it cannot ground an answer.

No located public material describes what the engine does when it cannot answer a Lexible question with confidence. The product assigns risk ratings and flags issues, and the vendor publishes an accuracy figure, but no abstention path, unanswered-question handling or confidence signal is described on the surfaces read; the Accuracy page was not opened. Demo page and home page checked 6 September 2026.

Source: Operator VerifiedAs of Sep 6, 2026

Fabricated Citation Record

Does a public court record exist involving output from this product?

None located

No court order, opinion or disciplinary record naming this product has been located as of the date shown. This is a statement about the public record, not a finding about the product.

No court order, opinion or disciplinary record naming ThoughtRiver or Lexible was located as of 6 September 2026. The AI Hallucination Cases database maintained by Damien Charlotin was searched on both names together with a general search for court findings; results returned sanctions involving general-purpose chatbots and commentary, none of which names this product. This is a statement about the public record, not a finding about the product; a contract review tool that cites no authority carries a remote exposure on this signal.

Source: Operator VerifiedAs of Sep 6, 2026Evidence
Professional Responsibility

Bar Guidance Alignment

Has the vendor engaged in public with the ethics opinions its buyers are bound by?

Not addressed

No located public material engages with bar or ethics guidance.

No located public material names an ethics opinion, bar rule or professional responsibility framework. The vendor states its questions are trained by in-house lawyers and offers law firms a pre-screening service line, but no guidance from any bar or regulator on lawyers' use of AI is named on the surfaces read; the terms of use and the EU AI Act statement were not opened. Home page, demo page and DPA checked 6 September 2026.

Source: Operator VerifiedAs of Sep 6, 2026

Billing and Fee Posture

Does the vendor address what happens to the bill when the work takes an hour instead of six?

Savings claims only

Public materials claim time savings without addressing billing or disclosure, and the product sits inside a fee relationship between a lawyer and a client where those savings would change the bill.

Law firms are a named buyer and partner segment and the published position on the bill is a savings claim: the Shoosmiths quote sets three minutes of platform review against four hours of qualified lawyer time, and a 2019 vendor article pitched pre-screening as a new recurring revenue stream for law firms. Nothing addresses how AI-assisted review is recorded or disclosed on a client's bill. Demo page and home page checked 6 September 2026.

Source: Vendor PublishedAs of Sep 6, 2026

Outside Counsel Guideline Readiness

Can a firm get this vendor through a client’s AI clause without a bespoke negotiation?

Subprocessors listed

A current subprocessor or model provider list is published.

A current sub-processor list is published: Microsoft Azure in the United Kingdom for infrastructure, Twilio SendGrid in the United States for account emails, Okta in the EU for authentication, Abbyy Vantage in the EU for document conversion and Zoho Desk in the EU for support, each with data categories, framework and processing operations, and the transfer mechanism for Twilio. The list names no language-model provider although the engine is stated to run on several large language models, so a firm cannot answer its client's model-provider question from it; that gap is why the row sits at this value. Surfaces checked 6 September 2026.

Source: Vendor PublishedSummary of sub-processors who may process Personal Data under the AgreementAs of Sep 6, 2026Evidence

Court Disclosure Support

If a judge’s standing order requires an AI disclosure, can the product produce one?

Partial record

Some elements of the record are available, short of a document level export.

Some elements of a review record are available and no export of an AI verification record is described. The Digital Issues List records every issue the engine flagged against the playbook, its risk level and resolution status, and can be shared with colleagues or downloaded as a PDF, which is a per-contract record of what the AI found and what a person resolved. Nothing states that the model used, its sources and the human verification can be exported for a court, and the product produces no court-facing work product. Vendor-supplied feature description read 6 September 2026.

Source: Vendor Publisheda checklist of all issues in a contract, only high risks, only unresolved issuesAs of Sep 6, 2026Evidence
Contact

Correct a record, or ask how something was graded

Every grade and every signal on this index is drawn from public sources and dated. If a record is wrong, out of date, or missing an artifact the index did not locate, send the source and it will be reviewed and the record redated. Vendors are welcome to submit documentation. Nothing on this index is for sale, including a listing, a placement, or a grade.

AI Legal Index

The AI Legal Index is an independent index that tracks changes to AI vendors in legal. It holds 61 vendors across 9 categories, each graded on the same 15 capability axes and recorded against 12 legal signals, from public sources. No vendor pays for inclusion, placement, or rating.

Index Status
Last index update
September 6, 2026
The AI Legal Index is an editorial reference. It is not a regulatory body, not a law firm, and nothing published here is legal advice or a recommendation to retain or avoid a vendor. Records are verified against published sources, bar guidance and public court records. Where a record reads not addressed, the material was not located in public sources on the date shown. See the Methodology page for evaluation standards and limitations.
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