Operational Software Assurance is a market term for protecting software after it has been deployed, especially in embedded, industrial, or other long-lived systems. It shifts attention from pre-release testing to the operational phase, when code is already in the field and may be hard to patch, recompile, or recertify.
It matters because attackers target deployed software, not just source code. In practice, OSA-style controls focus on inventory, runtime hardening, telemetry, and compliance evidence. That can include an SBOM to identify vulnerable components, protections that make exploitation harder at runtime, and monitoring that helps defenders distinguish normal faults from malicious behavior. These controls are useful compensating measures, but they do not replace secure development, patch management, segmentation, or formal assurance processes.