Royalty licensing in vertically related markets
比较了垂直市场中按单位产量和按销售额两种专利许可费合同，发现许可方总是偏好按单位产量收费，但按销售额收费对消费者和总福利的正面影响更大。
We compare two royalty licensing contracts: per-unit and ad valorem in a vertical market. The licensor always prefers a per-unit over an ad valorem royalty contract. Licensing has a greater positive impact on both consumer and total welfare under an ad valorem royalty.