Casetext

Casetext was an artificial intelligence-powered legal research and technology platform developed to help lawyers, law firms, and corporate legal departments conduct legal research, analyse documents, and prepare legal work more efficiently. Founded in 2013 and headquartered in San Francisco, California, the company focused on using artificial intelligence and machine learning to make legal information easier to find, understand, and apply. Its technology was designed to reduce the time legal professionals spent searching through cases, reviewing documents, and identifying relevant legal authorities.

Casetext initially gained recognition for making legal research more accessible through an online platform that combined legal materials with technology designed for the needs of practising lawyers. One of its best-known products was CARA, short for Case Analysis Research Assistant. CARA used natural language processing to analyse legal documents and identify relevant cases and authorities that could support a lawyer’s research. Instead of relying only on traditional keyword searches, users could provide a legal brief or other litigation document and receive research results tailored to its arguments, facts, and legal issues.

A key advantage of CARA was its ability to understand the context of a legal document. Traditional legal research tools often require users to identify the right search terms before locating relevant cases. CARA was designed to examine the substance of a document and identify authorities that might otherwise be missed. This helped legal professionals discover decisions relevant to their arguments and identify additional research materials. The system was also expanded to work with litigation documents that did not necessarily contain case citations, such as complaints, allowing it to identify relevant facts and legal issues from the document itself.

Casetext later expanded its technology beyond traditional legal research. Its products included tools for case law research, document analysis, legal writing, and litigation preparation. The company’s approach combined artificial intelligence with legal content and research workflows to help professionals complete repetitive tasks more efficiently. Its technology was particularly relevant to litigation lawyers, legal researchers, law firms, and in-house legal teams handling large volumes of legal information.

In March 2023, Casetext introduced CoCounsel, an AI legal assistant powered by OpenAI’s GPT-4 technology. CoCounsel represented a major development in the company’s product offering because it moved beyond search and retrieval into more advanced legal work. The assistant was designed to help lawyers review documents, conduct legal research, prepare deposition materials, and analyse contracts. Users could give instructions in natural language and receive structured outputs intended to support their professional work.

Document review was one of CoCounsel’s important capabilities. Legal professionals frequently need to examine lengthy documents to identify key facts, obligations, risks, and relevant information. CoCounsel was designed to assist with this process by summarising documents, extracting important details, and answering questions about their contents. This could help lawyers prepare for cases, understand large collections of evidence, and identify information requiring closer attention.

The legal research functionality allowed users to ask questions and obtain research assistance in a conversational format. Rather than constructing multiple search queries, lawyers could describe the legal issue they were investigating and use the assistant to develop their research. This was intended to make legal research more accessible while allowing professionals to spend more time evaluating the legal implications of the information retrieved.

CoCounsel also supported deposition preparation. Preparing for a deposition can involve reviewing pleadings, witness statements, correspondence, contracts, and other case documents. The assistant was designed to help lawyers identify important facts and develop questions based on the available materials. This could support the preparation process by helping legal teams organise information and identify areas that deserve further investigation.

Contract analysis was another area covered by CoCounsel. Lawyers and corporate legal departments regularly review agreements to identify important provisions, compare terms, and understand contractual obligations. AI-assisted analysis can help locate relevant clauses and summarise key information, making it easier to conduct an initial review. Professionals must still verify the results and assess their relevance to the specific agreement and transaction.

Casetext’s technology was intended to support legal professionals rather than replace their expertise. Legal research and document analysis require careful interpretation of facts, jurisdiction, procedural rules, and applicable authorities. AI-generated information can assist with initial research and organisation, but lawyers remain responsible for checking sources, evaluating the accuracy of the output, and deciding how it should be used in legal work. This is particularly important when preparing court documents, advising clients, or making decisions that could affect legal rights.

The company’s growth attracted the attention of Thomson Reuters, a global provider of legal, tax, accounting, and professional information services. In June 2023, Thomson Reuters announced an agreement to acquire Casetext for US$650 million. The acquisition was completed on 17 August 2023. At the time, Thomson Reuters highlighted CoCounsel as a significant part of the acquisition, describing it as an AI legal assistant that could support document review, legal research memoranda, deposition preparation, and contract analysis.

Following the acquisition, Casetext’s technology and product capabilities became part of Thomson Reuters’ broader legal technology strategy. CoCounsel developed into a wider professional AI offering connected with Thomson Reuters legal research and information products. Its current successor offering provides AI-assisted legal research, document analysis, drafting, and professional workflows supported by Thomson Reuters content.

The modern CoCounsel environment connects with products such as Westlaw and Practical Law and supports Microsoft 365 workspace integrations. This allows legal professionals to use AI-assisted capabilities within familiar working environments and access research and drafting resources as part of their wider legal workflows. The current product portfolio includes different plans for law firms and corporate legal departments, with features varying according to the selected subscription.

Casetext’s original contribution to legal technology was its focus on applying artificial intelligence to the practical tasks lawyers perform every day. CARA helped demonstrate how machine learning could improve legal research by considering the context of a document, while CoCounsel brought generative AI into document review, research, and litigation preparation. These developments helped establish a foundation for the broader use of AI in professional legal services.

Overall, Casetext played an important role in the development of AI-powered legal research and document analysis. Its technology helped lawyers discover relevant legal authorities, review documents, prepare for depositions, and analyse contracts. Although Casetext is no longer offered as a separate standalone platform, its technology and product direction continue through Thomson Reuters and CoCounsel. For organisations researching the original product, it is important to distinguish Casetext’s historical features from the current CoCounsel subscription and product offering.