Common Citation Document (CCD) is a web application that allows users to search for and view all documents cited by the EPO, JPO and USPTO in the search process for applications for the same invention pending simultaneously at the three Offices.The creation of the CCD application is result of process of technical harmonization at the international level aimed at establishing an appropriate infrastructure to facilitate greater integration of the global patent system. It was initially a patent information tool developed by the Trilateral Offices (EPO, JPO and USPTO) to provide single point access to citation data for their examined patent applications, and later extended its coverage to citation data from the two remaining IP5 Offices (China and South Korea).

The Common Citation Document (CCD) application aims to provide single point access to up-to-date citation data relating to the patent applications of the IP5 Offices. It consolidates the prior art cited by all participating offices for the family members of a patent application, thus enabling the search results for the same invention produced by several offices to be visualized on a single page. The CCD application is a tool that may be useful not just as an alternative to subscription-based citation features but as a supplement, since it provides additional data for EPO citations.

The CCD application includes the capability to view full-text of cited patent documents, the division of cited documents in a list by source of citation and connection to a specific patent application, the category of relevance for EPO citations, a compilation of “classifications and fields searched” for an entire patent family, and a timeline view to illustrate the time span for a collection of citations.

The CCD allows users to view citation data for both patent families and individual family documents. The CCD additionally provides the category of relevance, details on the relevant sections within the cited document, and the claims of the original document to which the citation document is relevant (for EPO citations).

The data coverage concerning the main offices, include:

EP citations: Both patent and non-patent citations and covers all possible procedures: applicant citations, search citations, examination citations, observations by third parties and opposition citations.

US citations: References to both patent and non-patent citations and covers only applicant and search citations.

JP citations: References to patent citations and covers all search, examination, opposition and appeal procedures, but does not include applicant citations.

WO citations: References to both patent and non-patent citations and covers only applicant and search citations.