The covered entity (CE), Valley Health System, reported that its business associate (BA), Inova Health System, experienced a cyber-attack that affected the protected health information (PHI) of approximately 13,596 individuals. The PHI involved included names, addresses, dates of birth, Social Security numbers, medical record numbers, and patient identification numbers. The BA notified HHS, affected individuals, the media, and posted substitute notice on its website. The CE also notified HHS. In its mitigation efforts, the BA implemented additional administrative, technical, and security safeguards to better protect PHI, and retrained its staff.