Early identification of important patents through network centrality

TL;DR

This paper demonstrates that using an age-normalized network centrality measure, rescaled PageRank, enables earlier identification of significant patents in the US patent citation network, outperforming simple citation counts.

Contribution

The study introduces rescaled PageRank for early detection of impactful patents, accounting for network topology and temporal factors, advancing patent analysis methods.

Findings

Rescaled PageRank identifies significant patents earlier than citation count.

Patent citation dynamics are slower than scientific papers, complicating early detection.

High-impact patents tend to cite other high-impact patents, similar to scientific literature.

Abstract

One of the most challenging problems in technological forecasting is to identify as early as possible those technologies that have the potential to lead to radical changes in our society. In this paper, we use the US patent citation network (1926-2010) to test our ability to early identify a list of historically significant patents through citation network analysis. We show that in order to effectively uncover these patents shortly after they are issued, we need to go beyond raw citation counts and take into account both the citation network topology and temporal information. In particular, an age-normalized measure of patent centrality, called rescaled PageRank, allows us to identify the significant patents earlier than citation count and PageRank score. In addition, we find that while high-impact patents tend to rely on other high-impact patents in a similar way as scientific papers, the patents' citation dynamics is significantly slower than that of papers, which makes the early identification of significant patents more challenging than that of significant papers.