We consider an infinitely repeated platform competition in a market with network externalities. The platform that dominated the market in the previous period becomes the incumbent in the current period. We examine the effect of an antitrust policy that prohibits both platforms (symmetric regulation), or just the incumbent (asymmetric regulation) from charging predatory prices. We show that symmetric regulation decreases consumer surplus and does not affect efficiency. Asymmetric regulation increases consumer surplus and improves welfare when the size of the market remains constant over time. Yet, when market size varies over time, this policy may lead to inefficient entry.

中文翻译：

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规范具有网络外部性的市场中的平台竞争：掠夺性定价限制会增加社会福利吗？*

我们考虑在具有网络外部性的市场中无限重复的平台竞争。上一时期占据市场主导地位的平台成为当前时期的主导者。我们研究了禁止两个平台（对称监管）或仅禁止现有平台（非对称监管）收取掠夺性价格的反垄断政策的影响。我们表明，对称监管会减少消费者剩余，但不会影响效率。当市场规模长期保持不变时，不对称监管会增加消费者剩余并改善福利。然而，当市场规模随时间变化时，这一政策可能会导致进入效率低下。