A designation regime is a legal framework that lets a regulator identify specific entities, such as vendors, service providers, or operators, and place special obligations or restrictions on them. Instead of applying the same rule to every company, the authority designates the few that present higher risk or greater systemic importance.
In cyber security, this matters because not all suppliers are equal. A cloud provider, managed service provider, or software vendor with deep access to many customers can become a concentration risk and a supply chain attack path. A designation regime can support defenses by requiring audits, stronger reporting, resilience testing, access controls, or even limits on who may serve critical systems. For attackers, these regimes raise the bar by forcing the most sensitive dependencies into clearer oversight and accountability.