CoCounsel vs Vincent AI: pricing, features and which to choose

CoCounsel is a professional legal AI assistant made by Thomson Reuters and descended from Casetext's product of the same name. Casetext launched CoCounsel in March 2023, and Thomson Reuters announced a $650 million acquisition of Casetext that year. The product now sits across Thomson Reuters' legal portfolio rather than operating as an independent Casetext service. Thomson Reuters said in February 2026 that one million professionals across 107 countries and territories had chosen CoCounsel across legal, tax, audit, compliance, and related products. Legal users are the clearest audience, including litigators, transactional lawyers, in-house teams, and firms that already buy Westlaw or Practical Law. The acquisition brought Casetext's product expertise into Thomson Reuters, while the current offering adds licensed content and broader distribution.

A typical workflow starts with a natural-language request, an uploaded file, a connected document repository, or a Thomson Reuters research collection. Users can summarize and compare documents, extract information, identify missing provisions, prepare deposition materials, build timelines, draft text, and check contract policies. Knowledge Search can find material in a firm's own repositories, while Browse Library exposes expert-built prompts and skills. Agentic workflows handle multi-step assignments, and Deep Research gathers and synthesizes authority for a more complete answer. Outputs are designed to include citations or links where selected content supports them, but lawyers still need to check quotations, authorities, privilege, confidentiality, and final work product before relying on it. The system assists legal judgment rather than replacing professional review.

CoCounsel's strongest case is a research-heavy practice already invested in Thomson Reuters content. Its citations, document skills, repository connections, Microsoft 365 integrations, and agentic workflows can reduce switching between research and drafting tools, though outputs remain subject to legal review. Law firms should compare it with Harvey, Lexis+ AI, and Legora rather than assume the content advantage settles the decision. Independent 2025 benchmarking placed CoCounsel among the stronger tools across document tasks, while Law360 reported that some early adopters preferred Harvey or Legora for interface and workflow reasons. Privacy terms prohibit using customer prompts and content to train third-party models, with configurable retention, encryption, and zero-retention model APIs. Choose CoCounsel when Westlaw or Practical Law is central and authoritative citations matter most.

Vincent AI is a legal research and drafting assistant made by vLex, which became part of Clio after the acquisition completed on 2025-11-10. vLex says Vincent was introduced in 2018 and launched globally in 2024, while an independent VLAIR report describes an October 2023 release. The product targets law firms and legal teams rather than casual chatbot users. It retrieves from vLex's editorially enriched library, which vLex describes as containing more than one billion documents across 110 jurisdictions. vLex merged with Fastcase in 2023, placing Vincent within a larger legal research business. The 2026 branding is Vincent by Clio/vLex, and the service remains active after the acquisition.

Vincent starts with a question, document or other source material, then retrieves relevant material from vLex's legal library and produces cited research or analysis. It can build arguments, compare cases and contracts, summarize documents, draft text, redline files, translate content, analyze transcripts and audio or video, and create tables. Agentic Mode plans and executes multi-step workflows. Users can work through Word with native Track Changes in beta, mobile capture and voice, Legal Pad, and connectors for iManage, NetDocuments, SharePoint and Google Drive. Optional web search labels web sources separately. Vincent Studio, generally available to Enterprise customers in January 2026, lets publishers create governed Workflows, Tasks and Steps without code.

Citations and retrieval do not remove the need for legal verification. A Nevada Bar review scored Vincent 36.5 out of 50 and reported missed administrative decisions, generic multi-state answers, complex-query accuracy issues, and limited integration and customization. VLAIR testing produced task scores from 53.6% to 72.7%, with Vincent sometimes refusing when its corpus lacked support. Westlaw Precision AI offers Westlaw's incumbent research workflow, while Lexis+ AI provides LexisNexis content and Shepard's. Harvey offers broader bespoke legal-work automation, whereas Vincent centers cited retrieval from a licensed legal database. Firms needing global research and configurable legal workflows should pick Vincent.