Espacenet has now reached the milestone of 140 million patent documents, making it one of the most prized patent search tools in terms of patent data coverage.
The USPTO's Public PAIR system was retired on 1 August 2022 and has been replaced by Patent Center.
Patent Center is the patent filing, retrieval and account management system of the USPTO. Patent Center provides access to all publicly available documents - patent applications (including provisionals), issued patents, design applications, Patent Cooperation Treaty applications, international design registrations, supplemental re-examinations and reexaminations. Using the application number, you can view all the details of a US patent application or granted patent. You will also find links to the Global Dossier and Maintenance Fees services.
If you use APIs or need to download data in bulk, go to the USPTO's Patent Examination Data System.
Watch this USPTO video to learn more about the transition from the Public PAIR system to Patent Center, and about Patent Center functionality.