Patents are a very useful tool for supporting innovations by setting incentives for companies to invest in research and developments. However, only those innovations should be protected by a patent that are truly inventive. Otherwise, patents might actually end up stifling innovations rather than supporting them. This happens in the case of patent thickets where there are overlapping patents that block each other. DIETMAR HARHOFF explains that this situation should be avoided by the mechanism of opposition: After the patent is granted by the patent examiner, third parties have the opportunity to oppose the examiner’s decision. As described in this video, the researchers used graph theory to analyze patent thickets involving three companies to uncover in which situations this instrument fails. Their findings indicate that, if a patent holder is embedded in such a thicket, they are less likely to challenge a patent application to avoid an escalation between the parties that might end up in court. Furthermore, if there is a large number of companies that could oppose a certain patent, the incentive for any of these companies to oppose is reduced as only one of them has to shoulder the costs of the process while all of them benefit.