Open AccessPatent classifications as indicators of intellectual organization
Author(s) -
Leydesdorff Loet
Publication year - 2008
Publication title -
journal of the american society for information science and technology
Language(s) - English
Resource type - Journals
eISSN - 1532-2890
pISSN - 1532-2882
DOI - 10.1002/asi.20814
Subject(s) - computer science , patent analysis , treaty , citation , intellectual property , patent visualisation , co citation , citation analysis , data science , information retrieval , business , knowledge management , political science , world wide web , law , operating system
Using the 138,751 patents filed in 2006 under the Patent Cooperation Treaty, co‐classification analysis is pursued on the basis of three‐ and four‐digit codes in the International Patent Classification (IPC, 8th ed.). The co‐classifications among the patents enable us to analyze and visualize the relations among technologies at different levels of aggregation. The hypothesis that classifications might be considered as the organizers of patents into classes, and therefore that co‐classification patterns—more than co‐citation patterns—might be useful for mapping, is not corroborated. The classifications hang weakly together, even at the four‐digit level; at the country level, more specificity can be made visible. However, countries are not the appropriate units of analysis because patent portfolios are largely similar in many advanced countries in terms of the classes attributed. Instead of classes, one may wish to explore the mapping of title words as a better approach to visualize the intellectual organization of patents.