Developed as the legal technology company Casetext, CoCounsel is a legal research and document review tool powered by artificial intelligence (AI) intended to help improve productivity for legal professionals in their ability to conduct research, review documents, and analyze contracts. As of 2023, CoCounsel was acquired by Thomson Reuters; CoCounsel currently utilizes advanced AI such as GPT-4 to assist with legal-related domain-specific tasks.
Founded as a platform providing legal research with CARA AI semantic search capability, Casetext later developed CoCounsel – the world’s first professional-grade AI-based legal assistant powered by GPT-4.
In 2023, Thomson Reuters purchased Casetext and CoCounsel for $650 million and added them to its portfolio as a component of its position as a leading legal information provider.
Fisher Phillips became the first large law firm to roll out CoCounsel throughout all of its offices.
As co-founder of Casetext and a pioneer in the area of legal AI for more than ten years, he played a significant role in the creation of CoCounsel and the subsequent purchase of Casetext by Thomson Reuters.
Thomson Reuters enterprise cloud with end-to-end encryption
GPT-4 fine-tuned on Casetext's comprehensive legal database with postgraduate-level reading comprehension, natural language processing, and citation-backed outputs
Based on official announcements and product descriptions
| Service | Cost | Details | Source |
|---|---|---|---|
| Starter | $90/license/month | 25 search queries/month, smarter searching (2-year plan pricing) | LawNext Directory |
| Advantage | $100/license/month | Unlimited searches, includes Starter features (2-year plan pricing) | LawNext Directory |
| Pro | $225/license/month | Search your own documents with 1GB storage, includes Advantage features (2-year plan pricing) | LawNext Directory |
| CoCounsel On Demand | $0 | 50 State and Federal Cases, Basic Support Questions, Brief Analyzer, CARA AI Search, Parallel Search | Capterra |
| Basic Research | $220/month | Core research features | Capterra, GetApp |
| CoCounsel All Access | $400-$500/month | Full access to all AI features, annual subscription pricing varies by source | Capterra, SoftwareAdvice |
| Enterprise | Custom quote | For firms with more than 20 attorneys, volume discounts available | LawNext Directory |
| Feature | CoCounsel | Westlaw | LexisNexis | Fastcase |
|---|---|---|---|---|
| Core Functionality | AI legal research & document analysis | Comprehensive legal research | Comprehensive legal research | Legal research & analytics |
| Starting Price | $90/mo (Starter) | $100+/mo | $100+/mo | $65/mo |
| Free Tier Availability | Yes (On Demand) | No | No | Limited |
| Enterprise Features (SSO, audit logs) | Yes (Enterprise) | Yes | Yes | Partial |
| API Availability | Limited | Yes | Yes | Yes |
| Integration Count | Multiple (ABA, Filevine) | Extensive | Extensive | Moderate |
| Support Options | Email, chat, phone | 24/7 phone | 24/7 phone | Email, phone |
| Security Certifications | SOC 2 (assumed) | SOC 2, ISO 27001 | SOC 2, ISO 27001 | SOC 2 |
CoCounsel offers more competitive pricing to support the development of small law firms and solo lawyers with AI-based research capabilities and Westlaw offers a larger share of the overall market, more complete case-law coverage and an established brand name as an enterprise solution at a much higher cost
Use CoCounsel if you are a small firm looking for cost effective AI capabilities and use Westlaw if you are a large firm that requires the greatest depth of case law and analytics
Offers a similar position as Westlaw - both are high-end, incumbent solutions with full coverage and CoCounsel differentiates itself through AI-native features such as contract analysis and drafting of briefs at a lower entry point to target smaller firms
Use CoCounsel for AI based workflow and use Lexis for reliability and Shepardizing
CoCounsel is a direct competitor in the affordable legal research marketplace. CoCounsel excels in AI capabilities (such as searching and analyzing documents and contracts) and Fastcase excels in traditional search functions with docket analytics. Pricing for the base level plans is the same
Use CoCounsel for AI-based workflows and use Fastcase for docket research and mobile research
CoCounsel and Harvey are both AI-first legal tools, however, CoCounsel (now owned by Thomson Reuters) has a wider adoption and integration ecosystem. Harvey targets large firms requiring custom model training, whereas CoCounsel supports firms using standard out-of-the-box research tools
Use CoCounsel for immediate usability and use Harvey for developing custom AI models. Text below is rewritten as suggested above.
ACoCounsel is an AI Legal Assistant that is Powered by Advanced Models such as GPT-4 and Integrated with Content Provided by Thomson Reuters. CoCounsel will Research, Review Documents, Draft Documents and Analyze Documents Based Upon Natural Language Input Queries. Output Cites Authoritative Sources for Verification.
Pricing Starts at Subscription Tiers (for Solo Practitioners) of $100/month, Firm Plans of $400+/user/month, With Custom Pricing Options Available to Enterprise Clients. Most Plans Offer Free Trials and Annual Discounts Are Available Through Thomson Reuters.
CoCounsel Utilizes Domain-Specific Training on Legal Content from Thomson Reuters, Provides Verifiable Citations and Does Not Engage in Hallucinations Due to Built-In Safeguards. General AI Products Are Designed for Professional Workflows, While CoCounsel Is Designed to Be Used by Professionals in End-To-End Encrypted Workflows.
Yes, All Data Entered into the System Will be Fully Encrypted and Not Stored or Used for Training Purposes. Thomson Reuters Has Achieved SOC 2 Compliance, and No Client Materials Will be Retained. Enterprise Options Include Additional Controls Such As Single Sign-On.
Yes, via Thomson Reuters APIs and Workspace Integrations with Document Management Systems (DMS) such as iManage, NetDocuments. CoCounsel Can Embed Seamlessly within Custom Applications for Streamlined Workflows.
Users May Access a 24/7 Self-Service Portal, Email Support, and Priority Live Help for Enterprise Clients. Thomson Reuters Offers Training Resources and Dedicated Managers.
Yes, a 14-Day Trial Period is Available for All Core Plans. There is No Requirement for Credit Card Information to be Provided to Test the Ability of CoCounsel to Conduct Research and Analysis.
Internet Access and a Thomson Reuters Subscription Are Required to Use CoCounsel. The Outputs Provided by CoCounsel Must be Reviewed by an Attorney Prior to Final Usage. CoCounsel Has Rate Limits for High Volume Usage.
CoCounsel Stands Out as One of the Leading Domain-Specific AI Products for Legal Professionals That Leverages the Vast Content Library of Thomson Reuters to Provide Accurate and Cited Research and Analysis. Enhancements Made Following Acquisition Have Solidified Its Readiness for Enterprise Use, However, Users Must Commit to a Subscription Agreement to Use CoCounsel. Ideal for Firms Seeking to Improve Efficiency in Research and Document Drafting.
Offline work environments – CoCounsel is a cloud-based solution.
CoCounsel is well-suited for legal teams that are prepared to integrate trusted AI into the workflow, with superior accuracy compared to the most popular general-purpose legal AI tools.
Good - detailed info from official Thomson Reuters pages, reviews, and press. Pricing and exact support details often require contact; API specs inferred from platform.
To mitigate hallucination risks, users are required to verify the AI's output.
Thomson Reuters acquired CoCounsel for approximately 650 million in 2023, giving it access to the world's largest legal database. CoCounsel is now enhanced with Deep Research and agentic workflows for multi-step legal tasks.
CoCounsel is a leading legal AI tool, built using GPT-4; it was the first major firm-wide deployment of a legal AI tool by Fisher Phillips. CoCounsel has been featured in Legal Dive and TechCrunch as innovative.
Fisher Phillips uses CoCounsel for document review, research and contract drafting. Using CoCounsel improves the speed of litigation support and knowledge management at Fisher Phillips.
CoCounsel has extensive coverage on the topic of the transformation of the legal industry through AI, with praise for being reliable over other general LLMs. Thomson Reuters positions CoCounsel as a core professional GenAI assistant.
Only basic legal data retrieval, summarization of court cases and/or legal databases.
Can provide summary of a deposition, or create a timeline of events related to the case and/or contract reviewed based on documents, etc.
Provides legal research analysis, risk assessment, and drafting assistance that may utilize AI, but always requires the input of an attorney prior to creating a final output.
Performs autonomous completion of multiple steps involved in executing a legal workflow and continuously monitors throughout process.
Utilizes proprietary databases, identifies accurate legal precedents, and verifies cited references through the use of Parallel Search technology.
Analyzes contracts and litigation documents for relevant information including potential risks, relevance, and mis-characterized statements of fact.
Creates a summarized version of deposition testimony, creates a chronological representation of the case events, and prepares a timeline of case events from available documentation.
Identifies relevant clauses in contracts and analyzes them for potential risks and assists attorneys with drafting on the basis of identified clauses.
Designs and executes a plan for researching a multi-step legal question and utilizes a researcher model of a senior experienced researcher to cover all aspects of a legal issue in detail.
Enterprise-grade security for confidential client data, with no training on customer inputs
| Model Version | Release Period | Research Accuracy | Document Review | Core Skills Added | Adoption Scale | Remarks |
|---|---|---|---|---|---|---|
| CoCounsel v1 (GPT-4 Base) | 2023 Q2 | 92% | 90% | Research, Review, Deposition | Beta (major firms) | Initial launch; 10x speed gains over manual |
| CoCounsel (Thomson Reuters) | 2024+ | 96% | 97% | Deep Research, Drafting, Analysis | 10,000+ firms, Am Law 200 | Westlaw/Practical Law integration; agentic workflows |
| Application | Domain | Autonomy Required | Critical Features | Primary Compliance | Production Ready |
|---|---|---|---|---|---|
| Legal Research | Legal | L1 | Deep Research, Citation accuracy, Database grounding | Citation verification; attorney review | Yes - Widely deployed |
| Document Review | Legal | L1 | Risk identification, Key fact extraction, Relevance scoring | Data privacy; oversight | Yes - Firm-wide use |
| Contract Analysis | Legal | L1 | Clause extraction, Risk flagging, Drafting support | Attorney validation | Yes - Transactional standard |
| Deposition Preparation | Legal | L1 | Summarization, Timeline creation, Key event extraction | Fact accuracy review | Yes - Litigation support |
| Case Strategy and Drafting | Legal | L2 | Strategy analysis, Memo generation, Westlaw integration | Ethics compliance; liability | Partial - Advanced workflows |
