This study analyzes the ownership-performance relationship in large-scale farms using extensive survey and farm accountancy data from Czech agriculture. Controlling for ownership endogeneity, no significant influence of ownership on financial performance was found. However, ownership concentration and managerial ownership positively effect labor productivity. Farm group analysis detects highly heterogeneous ownership form combinations and suggests that ownership endogeneity stems from mutual sources with economic performance. The results imply that one of these sources is management quality and its ownership transformation strategies. They further disclose that ownership structure and agency problems are more of a concern in larger farms.