Security engineering involves systematically applying the accumulated experience and best practices, such as regulatory security requirements, to identify a repeatable solution that is cost-effective, continuously improved, and fulfills security expectations of the stakeholders. However, security principles and regulatory requirements are rarely applied systematically during system design. We outline a stepwise process to extract domain concepts and apply a lightweight formal modeling language, Alloy, for the representation of regulatory requirements as early security patterns. These patterns, as a collection of constraints describing regulatory requirements provide a template for the systematic integration and analysis of these constraints in a system context. Each pattern defines a constrained solution space that can be enforced in subsequent phases of secure system development, testing and operation.