Software vendors need to manage the dependencies of the open source components used in their products. Without this management, license compliance would be impossible, export restrictions could not be maintained, and security vulnerabilities would remain unknown to the vendor.The management of these dependencies has grown in an ad-hoc fashion in most companies. As such, vendors find it hard to learn from each other and improve practices.To address this problem, we performed exploratory single-case study research at one large established software vendor. We gathered and analyzed the key challenges of tracking and documenting open source dependencies in products. We wanted to understand whether these ad-hoc solutions could be based on a single unified conceptual model for managing dependencies.Our study suggests that underlying the various point solutions that we found at this vendor lies a conceptual model that we tentatively call the product (architecture) model. In future cross-vendor work, we will investigate whether this conceptual model can be expanded to become a unifying model for all open source dependency management.