CoCounsel
#6 in AI for Legal & ComplianceThomson Reuters · 2× · last seen Sep 09, 2026
CoCounsel is an AI assistant by Thomson Reuters for law, tax, audit, compliance, and contract work. Originally launched on March 1, 2023 by legal tech firm Casetext as a GPT-4-based AI legal assistant, the product was expanded following Thomson Reuters' acquisition (completed August 2023) and relaunched in August 2025 as "CoCounsel Legal." It is tightly integrated with Thomson Reuters content such as Westlaw, Practical Law, and Checkpoint, supports agentic workflows (Deep Research, document review, research, drafting), and emphasizes source attribution and enterprise security (encryption, Zero-Retention, no use of customer data for model training). Pricing is not published publicly as a fixed price list but is determined through consultation.