The Breach Notification Rule is a HIPAA requirement that tells covered entities and business associates what to do after a breach involving unsecured protected health information (PHI). It defines when notice is required, who must be informed, and what the notification must generally include, such as the nature of the incident and the types of data involved.
In cyber security, this rule matters because disclosure is not just a legal afterthought; it is part of the response plan. When attackers steal, expose, or improperly access health records, organizations must determine whether the data was secured, whether a breach-risk assessment is needed, and whether patients, regulators, and sometimes the media must be notified. Defenders use this rule to guide incident response, log review, forensic analysis, and containment decisions. In real attacks, it becomes relevant when ransomware, misconfigured cloud storage, or vendor compromise exposes PHI and triggers formal notice obligations.