Thomson Reuters has released its own large language model, named Thomson. The company invested approximately $40 million to build the model in-house on an open-source foundation, training it exclusively on its own content from Westlaw, Practical Law, Checkpoint, and Reuters.
The first deployment appears in CoCounsel Legal through a new document-review feature called Tabular Analysis. Support for tax and the broader legal product lineup will follow later.
Thomson is owned by Thomson Reuters and is designed to reduce ongoing operating costs compared with relying solely on third-party models. The company has stated that no customer files were used in training. The model does not replace Checkpoint or Westlaw. CoCounsel will continue to route tasks to other models when those deliver better results. Thomson is not offered as a standalone product; it is embedded inside the software platforms customers already license.
For firms already using these tools, the practical next step is straightforward. Ask your Thomson Reuters representative which features currently run on Thomson, which still use other models, and what changes, if any, this introduces into daily workflows. Avoid applying the new model to client returns, research memos, or production work simply because the underlying engine has changed.
My I.T. Consultants is a managed service provider that helps organizations evaluate vendor-driven AI updates before they reach client files. If your practice uses Checkpoint, Westlaw, or CoCounsel and you want a clear assessment of the impact, contact our Athens office at 903-675-5431 during weekday business hours.
