Welfare Consequence of Common Ownership in a Vertically Related Market*
研究了垂直关联市场中共同所有权对福利的影响，发现其福利效果取决于下游市场竞争程度：当下游企业少、产品差异化大时，共同所有权可能改善福利。
We investigate how common ownership affects welfare in a vertically related market. Although common ownership mitigates the double marginalization problem and improves welfare, it restricts competition among downstream firms and harms welfare. We find that whether common ownership is welfare‐improving depends on the degree of competitiveness in the downstream market. Common ownership is more likely to improve welfare when there are fewer downstream firms and a greater degree of product differentiation. In other words, common ownership may improve welfare when competition in the downstream market is weak.