Two-dimensional Technology Profiling of Patent Portfolio

Noticing that some technology content is not reflected by patents' individual classification symbols but by the co-assignment of these symbols, this study proposes to represent the technology content of a patent portfolio using a two-dimensional matrix, referred to as the profile matrix of the portfolio. The element Mij of a profile matrix M counts the co-assignment frequency of symbols Ci and Cj, and the element Mii is the individual assignment frequency of symbol Ci. The profile matrix not only covers the traditional one-dimensional patent classification analysis, but also provides a more comprehensive picture to the portfolio's technologies. The profile matrix may be applied to detect the similarity or relatedness between patent portfolios, monitor the shift of an entity's RD direction, and discover the emergence of new, cross-disciplinary technology.