We study how ownership similarity between two firms affects the likelihood of an acquisition between them. Assortative matching arguments suggest that similarity between acquiring and target firms can encourage acquisition behavior, since more similar partners can better understand one another and combine resources in a more efficient way. Previous research has confirmed this expectation focusing on traits related to industry, strategy, and technology. We contribute to this literature by examining similarity in the type of dominant owner. We hypothesize and find evidence in a sample of 14,000 Italian companies that acquisitions are more likely to occur among firms with similar owners.