Legal APIs let you add legal capabilities without building from scratch. Every entry below is profiled with trust signals — pricing model, authentication requirements, CORS support, rate limits, and live uptime checks — so you can compare options and pick production-safe choices instead of guessing from a link list.
| API | Pricing | Auth | CORS | Health | |
|---|---|---|---|---|---|
| BCLaws Access to the laws of British Columbia | Free | No | No | Profile | |
| Brazilian Chamber of Deputies Open Data Provides legislative information in Apis XML and JSON, as well as files in various formats | Free | No | No | Profile | |
| CourtListener API CourtListener: free legal research API with court opinions, PACER data, and judicial financial disclosures. | Free | API Key | Yes | Profile | |
| CourtListener REST API Search case law, dockets, judges, citations, oral arguments, and federal court records. | Freemium | API Key | Unknown | Profile | |
| EPO European patent search system api | Free | OAuth | No | Profile | |
| Google Patents API Google Patents: search and retrieve patent documents, citations, and intellectual property data worldwide. | Free | API Key | Yes | Profile | |
| PatentsView API is intended to explore and visualize trends/patterns across the US innovation landscape | Free | No | Yes | Profile | |
| TIPO Taiwan patent search system api | Free | API Key | No | Profile | |
| USPTO USA patent api services | Free | No | No | Profile | |
| USPTO Patents API USPTO Patents API: search US patent and trademark office data, applications, grants, and publications. | Free | Unknown | Yes | Profile |
Start with pricing and auth: free tiers and no-auth APIs are fastest to prototype with. Then check CORS if your app calls the API from the browser, and health before you commit — a great API that's been down for a week will block your launch. Each profile below shows all of these signals plus rate limits where documented.