Privacy concerns inhabit professional cloud adoption. Assurance seals resulting from a third-party certification are frequently used from cloud service provider to provide privacy assurance for their customers. However, empirical findings on the effectiveness of assurance seals focusing on “who” issues those, even if customers also require the information why the assurance seal is valid and reliable. To fill this gap, we build on information integration theory and investigate the impact of certification authorities’ reputation and the quality level of an audit on customers’ perceived privacy within a professional cloud environment by using an experimental design including 43 professional cloud decision makers. We show that certification authorities’ reputation does not alone produce opinion change, it rather affects customers’ perceived privacy resulting from the quality level of an audit. Our findings have theoretical implications for the information integration theory and assurance seal research. We also discuss the managerial implications of our work for cloud service providers and certification authorities.