EPO vs USPTO

The European Patent Office's Open Patent Services (OPS) exposes bibliographic, legal-status, full-text, and image data drawn from Espacenet and the European Patent Register through a RESTful, XML-based interface secured with OAuth2 client-credentials. Non-paying registered users get up to 4 GB of data per week for free, with a EUR 2,800 annual subscription available for higher volumes. A live request to the OPS host returned a fair-use-quota rejection while still echoing the requesting Origin in its CORS headers, confirming cross-origin access is genuinely enabled rather than merely documented.

USPTO's patent data and query APIs now live under the agency's Open Data Portal (ODP) at data.uspto.gov, a single platform that folded in what used to be the Patent Examination Data System, Bulk Data Storage System, and several Developer Hub services. Every ODP endpoint sits behind api.uspto.gov, requires a free API key tied to a USPTO.gov account, and returns JSON with CORS enabled — confirmed live via an Origin-header probe that got back access-control-allow-origin: * on both the request and its OPTIONS preflight. The stored learning-and-resources page itself has been renamed to a 'Data and statistics' hub that links out to the ODP.