Innovation serves as the fundamental driving force for economic development. As the basic unit of economic society, the innovation investment of individual enterprises not only forms the foundation for their long-term development but also plays a vital role in shaping the global innovation landscape. A direct manifestation of corporate R&D innovation capabilities lies in both the quantity and quality of patents. However, patent quality cannot be assessed unidimensionally; metrics such as patent citations, patent grant ratios, technological coverage scope, and the number of patent claims all serve as criteria for evaluating patent quality.
Patent citation refers to the referencing of a patent by subsequent patent applicants or examiners, indicating technological relevance between two patents. Originating from the Science Citation Index (SCI), patent citations form a knowledge network akin to academic literature references. Around February 1947, the USPTO (United States Patent and Trademark Office) pioneered the inclusion of relevant references in authorized patent documents to evaluate patent claims. Today, patent citation information generally derives from two sources:
- First, references provided by inventors during the application process, cited in sections like "Background Art" of patent specifications to delineate differences between the invention and prior art while demonstrating novelty. For instance, the U.S. patent system mandates applicants to disclose all relevant technical materials through an Information Disclosure Statement (IDS); failure to do so may result in patent invalidation.
- Second, references added by patent examiners during the review process. To assess a patent's novelty and inventiveness, examiners conduct prior art searches to identify technologies closest to the claimed invention.
Patent citation data serves at least two critical purposes:
- Tracking technological evolution and knowledge flow. Since Narin (1994) introduced bibliometrics into patent analysis, patent citations have been recognized as objective indicators of knowledge linkages. If a patent cites prior patents, it implies the utilization of knowledge embedded in those earlier works. Citation networks reveal dynamic innovation processes and knowledge transfer patterns across sectors and industries.
- Measuring innovation quality and value. Innovation evaluation extends beyond quantity to quality, as the significance of patents varies substantially. Patent citations help assess patent quality and innovation value, complementing simplistic patent counts.
The seminal work Patents, Citations, and Innovations by Adam Jaffe and Manuel Trajtenberg establishes a framework for analyzing patent value and technological trends through citation relationships.
CnOpenData has systematically organized European Patent Information Data into a dedicated database, providing comprehensive and granular data support for related research.
Data Features
- Contains detailed information on both citations made by patents (forward citations) and citations received by patents (backward citations).
- Documents current legal status(法律状态) of each patent up to the present.
Time Coverage
1985-2024.12.31
Field Display
Sample Data
European Patent Basic Information Table
European Patent Citation Table
European Patent Cited Table
European Patent Transaction Table
European Patent Literature Reference Table
European Patent Classification Table
Data Update Frequency
Annual updates