The Intertemporal Consequences of Unauthorized Reproduction of Intellectual Property
在跨期框架下，未经授权复制对企业的损害可能远超静态模型预测，但复制品的承诺价值也可能使利润更高，这解释了企业为何偏好差异化版权执法及免费赠送精简版知识产品。
In an intertemporal framework, the harm to firms from unauthorized reproduction of their products may be significantly greater than that predicted by most static models; copying by some consumers reduces the appropriable surplus from all consumers—including those consumers lacking any propensity to copy. Somewhat paradoxically, however, the commitment value of copies may also imply that profits are higher with copying than without copying. It is therefore suggested that firms may prefer differential copyright enforcement and that the commitment value of copies may offer a strategic explanation for free giveaways of abridged versions of intellectual property and vertical product differentiation more generally.