Effects of Copyrights on Science: Evidence from the WWII Book Republication Program
利用二战期间版权弱化的外生变化，研究发现弱版权降低了获取成本，促进了后续科学研究，尤其惠及资源较少机构的科学家。
Copyrights, which establish intellectual property in music, science, and other creative goods, are intended to encourage creativity. Yet, copyrights also raise the cost of accessing existing work—potentially discouraging future innovation. This paper uses an exogenous shift toward weak copyrights (and low access costs) during World War II to examine the potentially adverse effects of copyrights on science. Using two alternative identification strategies, we show that weaker copyrights encouraged the creation of follow-on science, measured by citations. This change is driven by a reduction in access costs, allowing scientists at less affluent institutions to use existing knowledge in new follow-on research.