FS

The Functional Specification (FS, sometimes FRS) describes how the system will meet each User Requirement. For every URS line item, the FS describes the screens, fields, validation rules, calculations, e-signatures and reports that deliver it. It does NOT describe the underlying code or database — that is the Design Specification's job.

In GAMP 5 Category 4 (configured products like V5), the FS is owned by the supplier and tailored to the customer's configuration. V5 ships a baseline FS aligned to the validation pack URS; customer-specific configuration deltas (industry profile, signature workflows, label templates) are layered on top so the FS stays accurate without rewriting from scratch.