We analyze the extent to which private defensive litigation insurance deters patent assertion by non-practicing entities (NPEs). We study the effect that a patent-specific defensive insurance product, offered by a leading litigation insurer, had on the litigation behavior of insured patents’ owners, all of which are NPEs. We first model the impact of defensive litigation insurance on the behavior of patent enforcers and accused infringers. We show that the availability of defensive litigation insurance can have an effect on how often patent enforcers will assert their patents. We confirm this result empirically showing that the insurance policy had a large, negative effect on the likelihood that a patent included in the policy was subsequently asserted relative to other patents held by the same NPEs and relative to patents held by other NPEs with portfolios that were entirely excluded from the insurance product. Our findings suggest that market-based mechanisms can deter so-called “patent trolling.” (JEL: G22, K41, O34)

中文翻译：

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专利诉讼保险的效果：来自 NPE 的理论与证据

我们分析了私人防御性诉讼保险在多大程度上阻止了非执业实体 (NPE) 的专利主张。我们研究了一家领先的诉讼保险公司提供的专利特定防御性保险产品对被保险专利所有者的诉讼行为的影响，这些专利所有者都是 NPE。我们首先对防御性诉讼保险对专利执法者和被指控侵权者行为的影响进行建模。我们表明，防御性诉讼保险的可用性会影响专利执法者主张其专利的频率。我们从经验上证实了这一结果，表明保险单有一个大的，保单中包含的专利随后被主张相对于同一 NPE 持有的其他专利以及相对于其他 NPE 持有的专利组合完全被排除在保险产品之外的专利的可能性的负面影响。我们的研究结果表明，基于市场的机制可以阻止所谓的“专利流氓”。(JEL: G22, K41, O34)