Thomson Reuters has launched the next generation of CoCounsel Legal, bringing research, analysis, drafting and verification together in an agentic AI environment built specifically for legal professionals.
The new CoCounsel Legal is designed to move legal work from an initial question through to a defensible work product within a single workflow. It combines the company’s Westlaw and Practical Law content with tools for legal research, drafting, legal intelligence and matter management.
Built on Anthropic’s Claude Agent SDK, the platform can plan, reason and execute multi-step legal workflows instead of responding to isolated prompts. Thomson Reuters says its outputs remain grounded in verified, traceable legal authority and follow the company’s Fiduciary-Grade AI principles.
“The legal industry is moving beyond AI that simply generates answers,” said Raghu Ramanathan, President of Legal Professionals at Thomson Reuters.
The most significant new capability is Westlaw Brief Builder, which helps litigators move from legal research and issue analysis to a first-draft brief. Powered by Westlaw Deep Research, KeyCite and Practical Law, the tool can propose relevant facts, arguments and supporting authorities while leaving strategy, legal theory and final decisions to the lawyer.
CoCounsel Legal also introduces Workspaces, which provide matter-specific environments containing organizational documents, precedents and institutional knowledge. Context can be preserved across matters and teams, allowing legal professionals to build on previous work.
A Drafting Agent inside Microsoft Word lets users draft, edit and review agreements using natural-language instructions. The tool draws on Practical Law resources as well as an organization’s documents and playbooks.
For document-heavy matters, Tabular Analysis can review as many as 10,000 documents and answer up to 100 questions, returning the results in a filterable table. The capability is powered by Thomson, the company’s proprietary legal-focused large language model.
Another feature, Deep Research Verify, evaluates whether cited Westlaw and Practical Law authorities support specific legal assertions. The verification layer is intended to give lawyers greater confidence in work produced with AI assistance.
Thomson Reuters is also expanding CoCounsel Legal through external integrations. An enhanced connection with Claude allows legal professionals to access CoCounsel through Anthropic’s AI assistant and receive cited work grounded in Westlaw, Practical Law and their organization’s knowledge.
A forthcoming connection with Amazon Web Services will extend CoCounsel Legal into Amazon Quick and other AWS products. Beginning in October, an integration with Reveal will allow litigation teams to move reviewed evidence directly into CoCounsel for research, analysis and drafting without manually exporting and uploading documents.
Thomson Reuters says CoCounsel is now used by one million professionals across 107 countries and territories.
The next-generation experience is available immediately in the United States, with availability in Canada, the United Kingdom and Australia expected later in 2026.