Fortune favors the bold: firms involvement in patent opposition

Patent opposition is a key strategic weapon used in intellectual property (IP) battles. While existing literature primarily focuses on the characteristics of the opposed patents to explain the occurrence of opposition proceedings, the role of firms’ characteristics remains less explored. We argue that a firm’s experience with opposition proceedings reflects its IP capabilities, both in defending its own patent portfolio and in challenging the patents of competitors. Using a dataset of EPO oppositions filed between 1980 and 2015 in the field of cosmetic technologies, we examine whether previous outcomes of opposition proceedings are associated with the likelihood of being involved in future opposition cases. Our findings show that patent holders with a higher rate of past success in opposition proceedings are less likely to be involved in subsequent oppositions. In contrast, (potential) opponents with a higher rate of past success are more likely to engage in future opposition proceedings.