LexisNexis adds citation verification and 100,000-document vaults to legal AI

LexisNexis is bringing more of the work around a legal question into one AI workspace: finding sources, checking how they are used, and producing editable documents. The company announced the expansion of Lexis+ with Protégé on October 27, with a US rollout this month and global availability to follow.

The release targets a problem LexisNexis says surfaced repeatedly in hundreds of studies and focus groups involving more than 7,000 legal professionals in 2026. Lawyers described moving between AI systems, carrying instructions and context with them, reformatting generated work, and repeatedly checking citations and conclusions before relying on them.

Protégé can now bring together LexisNexis legal materials and a firm's own documents through document-management connections. Its connected sources include Lex Machina litigation analytics, Intelligize corporate disclosures, CourtLink court-docket information and Law360 reporting. These supply different kinds of information around a legal assignment, rather than just a collection of cases.

Lawyers can select sources themselves or let Protégé coordinate the models, tools, skills and sources for a task. LexisNexis calls that coordinating software a governed legal harness. The company says it maintains source visibility and customer permissions while deciding which resources to use.

For example, LexisNexis describes a litigation team requesting an assessment that combines legal authority, court records, analytics about a judge's rulings, news and the firm's earlier briefs. Protégé is designed to keep those categories distinct and link each to its source, rather than blend them into an answer without showing their origins.

Shepard's Verify extends checks across AI-assisted and lawyer-created documents. LexisNexis says it assesses citation status, quotations and whether the cited legal authority actually supports the statement being made. Built on Shepard's network of legal rules and their relationships, the feature is intended to go beyond confirming that a case exists.

Enhanced Deep Research adds a more structured research process. It develops a plan, examines governing legal authority and how that authority has been treated, then produces a sourced memorandum. The output includes an executive summary, a table of authorities and relevant counterarguments. These are company-described capabilities, not independent measurements of legal accuracy.

Vault also supports files up to 500 MB and 14 file types, including audio, video and images. Findings link back to their sources, including timestamps in deposition videos. Review Tables handle a different document task: ask one question across a matter's documents, see answers linked to source clauses, and export the findings to Excel with references intact.

Native Microsoft Word drafting within Protégé preserves styles, numbering, footnotes, tables of contents and authorities, comments and tracked changes. Document comparison is also supported, and outputs remain available in Excel, PowerPoint and PDF. That addresses the formatting work lawyers identified alongside research and verification.

• Workrooms add memory, including personal preferences, to matter spaces holding drafts, discussions, skills and citation checks. AI-generated briefings can orient a lawyer joining a matter, while material actions enter a tamper-evident audit log.
• The Skills Library adds 100 legal skills for repeatable assignments, including due diligence and contract comparison. Custom Skills Builder lets practitioners create their own capabilities from LexisNexis content and firm documents without coding.

The rollout does not give every customer the same workspace. Access to connected sources and individual functions depends on subscription, customer configuration and administrator permissions.