We estimate a structural model of procurement auctions with private and common value components and asymmetric bidders using detailed contract-level data on the German market for railway passenger services. Exploiting exogenous variation in the procurement design, we disentangle the asymmetries in private costs from asymmetries in information about the common value. While each asymmetry can rationalize the dominance of a firm, understanding its source is crucial for the evaluation of the auction design as welfare and revenue implications depend on the source of dominance. Our results indicate that the incumbent is slightly more cost-efficient and has substantially more precise information about the common value component. If the bidders’ strategic response to the common value asymmetry was eliminated, the median probability of selecting the efficient firm would increase by 48%-points.