This paper addresses the design of an information system for specification of complex configured products, such as the solar power plants or large intelligent buildings, which by nature are designed, constructed, installed, operated, and maintained through virtual consortium of enterprises. In other words, typically a number of virtual organizations are involved during the entire life cycle of these products. The involved companies include the equipment suppliers, business service providers, and tailored software system developers, that form a consortium typically coordinated and managed by an EPC (Engineering, Procurement, and Construction) contractor or a so called project developer. Furthermore, remote access is required through the cloud to different elements of the complex product’s specification, to effectively support these products. An approach and a set of mechanisms are introduced in the paper for effective cloud-based specification of such complex products. The addressed generic system supports different involved stakeholders with customization of the planned complex product, satisfying both their preferences and mandatory standard criteria. The specification system is being implemented as a generic pilot information system, supporting iterative specification of configured sub-products for the planned complex product. This information system also constitutes the base for the next step of this research, focused on semi-automating the process of sub-products cataloging and building an intelligent recommender for complex product configuration, in dialogue with the user.