Common ownership - when an investor holds shares in two or more companies - has recently attracted significant attention from policy-makers and researchers, studying mainly US firms. European firms, however, are different as top investors with large stakes, like governments, founding families...

We study the incentives of firms that hold partial vertical ownership to foreclose rivals. Compared to a full vertical merger, with partial ownership, a firm may obtain only part of the target's profit but may nevertheless be able to influence the target's strategy significantly. The target may...