USPTO Enriched Citation API

V1 | Patents

The Enriched Citation API provides the IP5 and the public with greater insight into the patent evaluation process. It allows users to quickly view information about which references, or prior art, were cited in specific patent application office actions, including: bibliographic information of the reference, the claims that the prior art was cited against, and the relevant sections that the examiner relied upon.

The Enriched Citation API provides the IP5 and the public with greater insight into the patent evaluation process. This API release marks one of the first production implementations of the usage of artificial intelligence (AI) for data extraction at the USPTO. This quick access to an organized and prioritized citation list helps users identify relevant prior art, ultimately improving the accuracy and consistency of the patent examination. It serves as a foundation for future enhancements to the patent examiner search system.


Empowered by state-of-the-art machine learning, AI, and natural language processing algorithms, the enriched citation API analyzes the structure and content of office actions. The API then uses sophisticated information extraction and entity extraction algorithms to accurately locate:

  • the statutes used by examiners,
  • the claims rejected based on prior art,
  • the particular prior art references cited, and
  • specific relevant sections in the cited prior art references used.


An entity resolution algorithm is then used to consolidate the extraction results with the reference lists in the application, including references cited by applicants and by examiners. The process is fully automated and highly tunable, and is able to incorporate feedback from manual reviewers to improve efficiency and accuracy.


Enriched Citation API List of Fields

Field Name



References listed by the applicant in an information disclosure statement in the application


X - where a document is such that when taken alone, a claimed invention cannot be considered novel or cannot be considered to involve an inventive step

Y - where a document is such that a claimed invention cannot be considered to involve an inventive step when the document is combined with one or more other documents of the same category, such combination being obvious to a person skilled in the art

A - state of the art, not prejudicial to the novelty, or inventive step of the claimed invention


Identifier for the reference cited in the office action


The create date of this record


The create user id of this record


References listed by examiner in a standard USPTO 892 form in the application


Inventor name of the reference cited


Internal document ID for the office action


Office action category, e.g., non-final office action or final office action


Mail date of the office action


Patent application number


Internal quality summary text


Apr 12, 2019