A business viewpoint on the system distinguishes a "source" model and a "target" model. The "source" model must reflect the system (and its environment) that currently exists and is under investigation. Requirements for systems reflect business ownerspsila, managerspsila and userspsila needs related to the "target" model. Consistency between the "source" and the "target" as well as completeness and traceability of the "target" model still is a challenge. This paper bases check of requirements on a formal business model of the "source" system. It is performed in a formal way by creating a topological model of the "source" systempsilas functioning, and mapping functional requirements for the "target" system onto this model. Further, this holistic view can be decomposed by userspsila goals. Thus a model of the "target" system (requirements) is in compliance with a model of the "source" system (the universe of discourse). Beside that requirements are more complete and traceable.