管制前沿论坛

（2022年第5期，总第54期）

In this paper, we analyze stable market segmentation where consumers are mobile among different markets. Free circulation is legally mandated by data protection regulations, which endogenizes market segmentation. We show that in every stable market segmentation, the producer surplus remains at the uniform monopoly level, and the consumer surplus takes a value between the buyer-optimal level and the uniform monopoly level. No consumer is worse off than the uniform monopoly: Anonymous consumers are charged with the uniform monopoly price, while other consumers trade their privacy for a discount. Therefore, our results justify the Pareto optimum of price discrimination and reveal welfare implications of current regulations.