中文摘要
批评者认为，专利筛选并不奏效，致使低质量专利获批并造成不必要的社会成本。我们构建了一个涵盖专利局审查、费用以及法院中内生的专利有效性挑战的综合框架，从理论和定量两个方面研究专利筛选。在我们的模型中，一些发明需要专利激励才能产生，而另一些发明并不需要；信息不对称由此产生了筛选的必要性。我们表明，由于有效性挑战具有内生性，即使法院能够完美无误地裁判，也无法解决筛选问题。使用美国数据校准的模型模拟结果显示，现行筛选机制远非完善：全部获授权专利中，近一半对应的发明并不需要专利激励。尽管我们发现现行专利制度创造了正的社会价值，但加强审查可以带来巨大的福利增益。如果再辅以对许可行为的反垄断限制，专利制度的社会价值还会更高。
Abstract
Abstract Critics claim that patent screening is ineffective, granting low-quality patents that impose unnecessary social costs. We develop an integrated framework, involving patent office examination, fees, and endogenous validity challenges in the courts, to study patent screening both theoretically and quantitatively. In our model, some inventions require the patent incentive while others do not, and asymmetric information creates a need for screening. We show that the endogeneity of challenges implies that courts, even if perfect, cannot solve the screening problem. Simulations of the model, calibrated on U.S. data, indicate that screening is highly imperfect, with almost half of all patents issued on inventions that do not require the patent incentive. While we find that the current patent system generates positive social value, intensifying examination would yield large welfare gains. The social value of the patent system would also be larger if complemented by antitrust limits on licensing.