In the public tender processes of large international contracts, the organizational legitimacy is considered a prerequisite to limit the risk of engagement with companies that do not have it. The instrument usually used by the contracting parties is the Pre-qualification Questionnaire, which acts as a real entry barrier for contractors to participate in subsequent tenders. In this research we analyze the legitimacy requirement in tender processes. We focus on large contracts, mainly for the public sector but not limited to, based on documents accessible through public digital media. The research defines and provides content to the variables that shape the different legitimacy sorts required to the organizations to participate in large construction and trade tenders. The results suggest that the legitimacy requirements to the bidders are multidimensional, which entails that to participate in public tenders several legitimacy dimensions are evaluated. The weight of the different kinds of legitimacy in relation to the legitimacy global requirements is also analyzed.