The official primarily responsibility for security of an Info System; who establishes sensitivity level and types of controls required to protect the IS and initiates system authorization activities.

The Information System Owner holds the primary responsibility for the overall security of an information system, defining its criticality and the security controls needed. They are also responsible for initiating and supporting the system's authorization process, ensuring its compliance with organizational and federal security policies.

The System Development Life-Cycle (SDLC) is a process for developing and maintaining systems, not an individual responsible for security.

The Risk Management Framework (RMF) is a structured process for managing security risks, not an individual responsible for security.

While a Designated Representative might act on behalf of an owner, the core responsibility lies with the Information System Owner.