Westlaw searches Westlaw.
Lexis searches Lexis.
Neither searches both.
Every major legal research platform is a walled garden. If the authority that answers your question lives in a treatise, encyclopedia, or reporter the other one owns, you don't find it. You pay per silo, per year.
The problem
Westlaw
Searches Westlaw content. Doesn't cross into LexisNexis holdings. CoCounsel now routes through Anthropic's Claude via MCP. Your firm needs to approve a new AI vendor before it works.
Lexis+
Searches Lexis content. Doesn't cross into Thomson Reuters holdings. Separate subscription from Westlaw. Most firms pay for both.
Clio + vLex
Clio acquired vLex for $1 billion. Clio users now search vLex's 110-country database. They don't get Prosser, Wright & Miller, or Collier without separate subscriptions.
The citation treatment engine
Every time a court cites a statute, treatise section, regulation, or opinion, Marcella extracts that relationship from the public record. The result: a map of how courts actually applied authority, across every publisher, without subscribing to each one separately.
21 live practice areas
10 million+ judicial opinions. 50-state statutory codes. Federal regulations. Growing every day via automated ingestors.
Contracts & Commercial
CUAD, UCC, contract case law
Intellectual Property
USPTO, PTAB, Federal Circuit
Immigration
USCIS, EOIR, Foreign Affairs Manual
Bankruptcy
Official Forms, UST guidance
Labor & Employment
NLRB, EEOC, DOL regulations
Estate Planning
ULC acts, state probate statutes
Criminal Law
USSG, criminal procedure
Construction
Mechanics liens, Miller Act, OSHA
Family Law
Family court opinions, ULC family acts
Securities & Corporate
SEC EDGAR, Delaware Chancery
Government Contracts
FAR/DFARS, GAO protests, COFC
Real Estate
HUD, recording statutes, zoning
Banking & Finance
OCC, FDIC, Dodd-Frank
Environmental
EPA, Clean Air/Water, CERCLA
Tax
IRC, IRS publications, Tax Court
Federal Indian Law
Mineral rights, tribal codes
Ethics
ABA Model Rules, 51 jurisdictions
Medical-Legal
Med-mal opinions, SSDI, WC boards
Sanctions & Export
OFAC SDN, EAR/ITAR
Carbon / ESG
CARB, SB 253/261, Paris Art. 6.4
CMMC / Cyber
NIST 800-171, CMMC assessment